## •').

State ofCalifornia AIR RESOURCES BOARD

STAFF REPORT: INITIAL STATEMENT OF REASONS FORRULEMAKING.

Technical Status and Proposed Revisions to Malfunction and Diagnostic System Requirements for 1994 and Subsequent Model-Year Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles and Engines (OBD II)

Date ofRelease: October
, 1994 Scheduled for Consideration: December 8, 1994 Agenda Item No.: 

## L-_-_j

This report has been reviewed by the staffofthe California Air Resources Board and approved for publication. Approval does not signify that the contents necessarily reflect the views and policies ofthe Air Resources Board. nor does mention oftrade

names or commercial products constitute endorsement or recommendation for use.State ofCalifornia r\.IR RESOURCES BOARD

StaffReport: Initial Statement ofReasons for Proposed Rulerriaking1

PUBLIC HEARING TO CONSIDERTECHNICAL STATUS AND PROPOSED REVISIONS TO MALFUNCTIONAND DIAGNOSTIC SYSTEM REQUIREMENTS FOR 1994 AND SUBSEQUENTMODEL-YEARPASSENGER CARS, LIGHT-DUTY TRUCKS, AND MEDIUM-DUTYVEHICLES AND ENGINES (OBD II)



### I. 

### INTRODUCTION Date ofRelease: October
, 1994 Scheduled f{)r Consideration: December 8, 1994 Agen,da Item No.: 

## L-_-_]

The Air Resources Board (ARB orBoard) originally adopted Section 1968.1 ofTitle 13, CaliforniaCode ofRegulations on September 14, 1989. This section contains the malfunction and diagnostic system requirements known as On-Board Diagnostics II or OBD II. The regulationrequires manufacturers to implement comprehensive monitoring systems on vehicles to detect and aid in the diagnosis ofmalfunctions within vehicle emission and emission-related components and systems. OBD II systems are being phased-in beginning with 1994 model year vehicles sold in California. With minor exceptions, the regulation requires that by the 1996 model year, all vehicles subjectto the regulation shall be equipped with OBD II systems.

When th.e OBD II requirements were adopted. the Board recognized the technology forcing nature ofsome aspects ofthe regulation. The Board, therefore, directed the staffto follow manufacturers' progress towards meeting the OBD II requirements, and to report back to the Board with proposed amendments should they be deemed necessary to ensure that the requirements would be effective and feasible within the required timeframe. In response to this direction. the staffhas already presented one update to the Board. in September of 1991.

Since the hearing in 1991, the staffhas continued to carefully follow manufacturers· progress in developing OBD

### Jl monitoring technologies, and believes that manufacturers have largely been able to design diagnostic strategies that satisfy the requirements. However, some

The discussion that follows is intended to satisfy th;:> requirements ofGovernment Code Section 11343.2 which requires a non-controlling, "plain-english" summary ofthe regulations be made available to the public.

1.

### concern continues to be expressed regarding specific monitoring requirements that will apply to future model Y"'::tr vehicles. Modifications to the OBD II requirements are being proposed to address these concerns. The ARB staffhad originally.intended to return to the Board within two years ofthe 1991 hearing to address any further OBD II concerns; bowever, it is onl.y recently that sufficient information has been available upon which to base proposed

. modifications (although a hearing was held in I

### 993 at the request ofone manufacturerto address potential compliance concerns in the 1994 and 1995 model years).
Additionally, the staffis proposing modifications based on the experience gained as**O~D** 

### II systems have been broughtto production. These modifications either address minor OBD II implementation concerns orclarify requirementsthat are sometimesmisunderstood.

II. BACKGROUND INFORJ\1ATION
Purpose ofOBD Svstems

OBD systems detect the occurrence ofmalfunctions within vehicle powertrains that

cause increases in emissions. As a result, the time between the occurrence ofsuch problems and necessary repairs is shortened, yielding lifetime in-use emission reductions from motor vehicles. OBD systems also generate diagnostic information to direct servicetechnicians to the specific area ofdetected malfunctions, orto otherwise informthe technicianregarding the performance ofthe vehicle.

HowOBD Svstems Work
Today'svehicles utilize on-board computers to carry outmany powertrain management functions, such as fuel metering, evaporative purge system control, and automatic transmission operation. The computers obtain the information necessary to carry-outthese tasks, such as engine speed and the amount ofair entering the engine, from an**~ay** 

### ofsensors installed on the vehicle. In addition to using sensor information for control purposes, the same information can be evaluated by the computerto determine ifcomponents and systems are working properly. Most emission control systems and components can be monitored in this way without the need for any additional hardware on vehicles. For a very few other cases, such as the evaporative control system, an additional sensor is necessary to provide key information to the computer regarding the performance ofthe system.

When an abnormality is detected, the vehicle operator is notified throughthe· illumination ofa malfunction indicator light on the instrumentpanel. The computer also stores a code in its memory identifying the ·malfunctioning component and the nature ofthe problem. Service technicians·download these standardized codes with a microprocessor-based diagnostic "scan tool.:'

")



# .... •OBD II Requirements

OBD II systems will replace systems designed to meet California's oriainal OBD e , requirements, kno\v11 as OBD 

### I. OBD I required monitoring offuel delivery, the exhaust 

### aas

. . e recirculatiOn (EGR) valve, and emission-related components that provide input information to the on-board computer. Under OBD II, the monitoringrequirements have been expanded to

covervirtually every emission control system and electronic componentthat can affect emissions when malfunctioning. Included are importantmonitoring strategies that were not considered feasible when the OBD I requirements were fommlated (for example, monitoring ofcatalyst efficiency, engine misfire, and evaporative system leaks).

Forthe systems and components that significantlyimpact emissions when malfunctioning, the OBD II regulation requires that manufacturers correlate system performance with emission increases. Generally, the OBD. II system must be able to determine when systemperformance has deteriorated tothe pointthat emissions will be in

excess of 1.5 times the vehicle's applicable standards. Systems and cpmponents that measurably impact emissions when malfunctionjng, but not to the extentthat this emission threshold will be exceeded, must be monitored fat function by the OBD II system (but not necessarily for degree ofperformance). Somein industryhave stated that it is inappropriate for the MIL to be illuminated for a malfunctionthat hasnot, by itself, caused vehicle emissions to exceed the applicable standards; however, monitoringrequirements for all powertrain systems that can affect emissions are necessary 

### in ordertopreventhigh emission levels (without an indication ofa malfunction) caused by a combinationofseveral otherwise minor emission related**proble~s.** At one time during theformulation ofthe OBD II requirements, the ARB staffconsidered requiring manufacturers to evaluatethe emission impact ofthe array ofpossible combinations ofemission-relatedproblemsthat can·occur on vehicles, and to illuminate the MIL when combinations resulting inhigh emissions occurred. However. manufacturers stronglypreferred single fault monitoring for measurable increases in emissions, even iftheincrease is small, in orderto reducethe amount ofdevelopmenttesting required, and to guard against recalls associated with not foreseeing everypossible highemission malfunction combination. This is the approach that has been adopted.

The OBD II regulation also includes specific requirements for stored fault codes and other dia£mostic information. Fault codes are standardized throughout the indus.trv based on


# - 

# - . Society ofAutomotive Engineers' specifications, and will be available to service technicians through a standardized communication link incorporated into each**~ehicle.** Standardization of the communicationprotocol will lead to the availability ofdiagnostic tools that will Work for every OBD'II-equipped vehicle make and model (separate tools are no longernecessaryto obtain diagnostic information from each make ofvehicle). Besides fau1t codes, the OBD II system will

### pro~'ide information regarding the vehicle ope:-ating conditions that existed at the time a malfunction was detected. This will enable servicetechnicians to recreate the conditions in order to better diagnose problems and to verify repairs, particularly those which may be intermittent. Continuously updated engi,ne parameter data will also be available to further help technicians efficiently**se~vice** emission-related problems

.

... .).

### OBD II and Inspection and Maintenance**Pro~rrams**


### The utility ofOBD II systems is in concept the same as an Inspection and Maintenance (liM)program (i.e., the idenrification and repair ofmalfunctioning vehicles). However, even with Oilifomia'sliMprogram (Smog Check), OBD systems are necessary to

more fully realize the potential air quality benefits from reducing in-use vehicle emissions. Further, OBD systems can be used to create a more effective, efficient, and less expensive liMprogram. ·

OBD 

### IIsystems will detect emission-related malfunctions as they occur, thereby reducing emissions from malfunctions that occurmonthsto potentially years before the next scheduled liM inspection. Many emission-relatedmalfunctions are unnoticeable to the vehicle operatorwithout an indication from the OBD system. Manufacturers implementing OBD II systemsforthe 1994model yearhave indicated to the ARB staffthat OJ?D II systems have proven very effectivein detecting vehicles thatwere builtwith defects that otherwise would have gone undetected. Such vehicles would have been operated for & 

### leasttwo years priorto going through an liMtest, but instead were fixed under¥.rarranty.

OBD II systems will also be able to detect malfunctionsthat would not otherwise be found even with a loaded-modetailpipe emissiontest. Suchtests are·conducted with the vehicle warmed-up. Therefore,the performance ofcritical-cold-start emissionreduction devices (e.g., electricallyheated catalysts, oxygen sensors, secondary air systems, and others)

cannot befully evaluated incurrentliMprograms, butaremonitored bythe OBD II system, Further, for practical reasons, liMtests generallyuse a genericpass/fail emissionthreshold for flagging high emitting vehicles. With OBD II, the moriitoring systems aretailored to the design ofthe vehicle and the emission standardsto whichthe vehicle is certified. As a result, malfunctions will be detected at much lowertailpipe emission levels with OBD II compared to, for example, the liM240 loaded mode emissiontest. These advantages are especially important for vehicles designedto meet California'sTransitional LowEmission Vehicle (TLEV), LowEmission Vehicle (LEV), orUltra LowEmission Vehicle (ULEV) emission standards. which achieve progressively more stringent emission levels primarilythrough reductions in cold-start emissions. ·

OBD II**Re~rulatorv** 

### Historv

The OBD II requirements were first adopted by the Board on September 

### 1**~.**

### _1989. The Board'sresolution (n_umber 

### 89-77) directed the staffto report back to the Board intwo year's time regarding the progress.ofmanufacturers towards complying with therequirements ofthe regulation which would be phased-in beginning with the 1994 model year.

On·September 12, 1991, the staffpresented the upd2.te requested by the Board. The Board found that most manufacturers had identified monitoring technologies capable of satisfying the requirements; however, work stiii !lad to be done to ensure that the monitoring systems developed would function reliably in customers· har1ds. In addition to providing an

4.f•

update. the staffproposed a number ofregulatory modifications based on knowledge gained since the regulation was first adopted. These modifications were made to address concerns expressed by manufacturers, to promote consistency with federal OBD requirements, and to improve the effectiveness ofthe requirements in light ofmonitoring technology advances made by the industry.

Among the most significant changes to the regulation that were adopted was the proposal.to separate catalystmonitoring requirements for vehicles meeting California'sLowEmission Vehicle program emission standards, and non-low-emission vehiclesmeeting less stringent emission standards (i.e., vehicles meeting California's equivalentto the federal Tier I standards). The requirements for Californianon-low-emission vehicles were designed to be consistent with the federal monitoringrequirements for the essentially identical TierI vehicles. However, the stafffelt that separate requirements were necessary for low-emission vehicle applicationsto better fulfill the goal ofidentifying**malfunct~ons** with respect to marginal exceedances ofthe emission standards. A more detailed discussion ofthe LEV catalyst monitoring requirements is included later in this report. Another significant modificatioi'} was the inclusion ofan evaporative system leak detection monitoring strategy. With the change, OBD II systems will be. able to ensurethe integrity ofthe full evaporative system whereas previously, onlyproper function ofthe evaporative purge components would have been monitored. Additional leadtime for the incorporation ofboth ofthese monitoring strategies was included in the ad

1 opted amendments.

The 1994 model yearmarked the first year ofthephase-in for OBD II implementation. As manufacturers scheduled to produce OBD II-equippedvehicles for the 1994 model year finalized their system designs, Ford Motor Company (Ford) revealed that two ofits monitoring strategies could notbe madeto meetthe minimumrequirements ofthe.regulation in time for production. As a result, Ford petitioned theBoard to seekrelieffrom these requirements based on its demonstrated good-faith effortto implement fully compliant OBD II systems in the 1994 model yearwhen, by the nature ofthe phase-inprovisions, it could have delayed the introduction ofthese systems to the 1995 or 1996 model years. The Executive Officer granted Ford'spetition and the Board adopted modifications to the regulation to permit limited relieffrom specific monitoring requirements on a case-by-case basis. Subsequent to the hearim.?.. a number ofother manufacturers have used the orovisions to**~** 

### -.

.**~** obtain an exemption. usually for minor monitoring systemdeficiencies.

Overall to date. the ARB staffhas approved the OBD II system designs for**~ore** than 3 5 engine families developed by 14 manufacturers. Fourofthe engine families are certified to the TLEV emission standards.· ·

5.

### III. TECHNICALSTATUS AND PROPOSED MONITORING SYSTEM AMENDMENTS

CATALYST MONITORING I.

As indicated earlier, at the 1991 OBD II Board Hearing, the Board adopted amendments that put into place separate monitoring requirements for low-emission vehicle applications, and non-low-emission vehicles. Fornon-low-emission vehicles, the requirement is based on theperformance ofthe catalyst system overall. A malfunction is to be indicated when the catalyst system has deteriorated to the pointthat vehicle emissions increase by more than 1.5 times the vehicle's applicable standardovertheemission level when near new (i.e., at 4000 miles). Thisrequirement has been accepted by.the industry and, accordingly, the staff proposes no amendments. However, some manufacturershave expressed concern with respect to the OBD II requirements for monitoring catalysts onlow-emission vehicles.

Bachrround

To meet California's stringent Low-Emission Vehicle standards, manufacturers will use
a variety ofsophisticated emission controlstrategies and advanced catalyst systems. While considerable attention is being focused on reducing engine-outemissions to the lowest possiblelevels, manufacturers will rely onelectronic fuel controls operating in conjunction ..\,·ith newly-developedcatalyststo further reduce hydrocarbon (HC), carbonmonoxide (CO), and nitrogen oxide (NOx) emissionsto regulated levels.**Emis~ion** control systems on virtually all newCaliforniavehicles include three-way catalysts. These catalysts consist of ceramic or metal honeycomb structures (commonly referred to as "substrates"), coated with preciousmetals such asplatinum, rhodium, orpalladium. Theseprecious metals ke dispersed within an aluminawashcoat containing ceria, and the substrates are mounted in a stainless steel container in the vehicle exhaust system. Three-waycatalysts are so-designated because they are capableofsimultaneously oxidizing HC and CO emissions into water and carbon dioxide (C02), and ofreducing NOx emissions (by reacting with CO and hydrogen) into elemental nitrogen, C02, and water.

This three-way conversion activity only takes place efficiently, hov:ever, when the fuel system operates at a single air-fuel ratio, called stoichiometric (where there isjustthe required amount ofair to completely burn all ofthe fuel in the engine). To achieve and maintain stoichiometric fuel delivery, manufacturershave incorporated closed-loop fuel contro-l systems that utilize an exhaust gas oxygen sensordownstream ofthe engine to provide feedback on the status ofthe air/fuel ratio being achieved. All closed-loop fuel control systems actively cycle the air-fuel ratio slightly above and belowthe stoic;hiometric point to maximize ·three-way catalyst conversion efficiency. -The precious metals are used to temporarily retain the HC, CO, and NOx molecules in the catalyst while the ceri.a in the \vashcoat is used to store and release oxygen which is needed to con:plete the reactions. Oxygen is stored in the catalyst during· the lean portion ofthe fuel system's cycling (i.e

.. when the air/fuel ratio is slightly higher than stoichiometric) and is released during the rich excursion. \Vithout ceria.

6.

### there would be insufficient oxygen at the active sites ofthe catalyst to achieve the most efficient performance.

.
As emission conversion efficiency ofcatalysts containing ceria deteriorates, generally the ·oxygen storage capacity is also diminished. Accordingly, oxygen storage can be used as 

## an indicator ofcatalyst performance, discriminating between catalysts with sufficient and insufficient oxygen storage capability. By utilizing the information from the upstream oxygen
sensor anda second sensor located downstream ofthe catalyst (orcatalysts), the oxygen storage canbe measured by comparing the oxygen sensor signals. In addition to being used for catalystmonitoring, the rear sensorcan be used to monitorand correct for front oxygen
sensor aging as needed to maintainthe stoichiometric air-fuel mixture at high mileage. With

aproperly functioning catalyst, the rear oxygen sensor signal will be fairly steady since the fluctuating oxygen concentration (due to the fuel system cycling about stoichiometric) at the inlet ofthe catalyst is damped by the storage and release ofoxygen in the catalyst (see Figure I). \Vhen a catalyst is deteriorated, such damping is reduced, causing the frequency and peak-to-peakvoltage ofthe rear oxygen sensor signal to approximate the signal from the oxygen sensor before the catalystbecause the catalyst is no longer capable ofstoring and releasing oxygen.

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### FIGURE 1
Properly Functioning Catalyst

Deteriorated Catalyst

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7Current Reauirement

. Currently, ihe OBD II regulation requires manufacturers to monitorthe front catalyst

on low-emission vehicles for deterioration in HC conversion efficiency. A malfunction is to be indicated when the efficiency ofthe front catalyst falls to between 50 and 60 percent based

on the Federal Test Procedure (FTP) driving cycle. Theregulation defines a front catalyst as the first "substrate" which receives untreated engine-outexhaust gas. A commoncatalyst system configurationplaces two ormore substrates into a single container, buteach substrate is considered a separate catalystfor purposes ofthe regulation (as illustrated inFigure 2). Manufacturers generally planto use a series ofcatalysts in the exhaust system to meetthe Low-EmissionVehicle standards (all certified TLEV'sto date use multiple catalyst substrates).



### FIGURE2 

## TypicalCatalystConfiguration
Catalystsubstrate#1 (frontcatalyst)

/

-Engine

Catalvstcontainers

The catalyst monitoring requirements currently adopted for low-emission vehicles

were designed to provide for the detection ofcatalyst system deterioration on vehicles with multiple catalysts by the time vehicle emissions marginally exceed the applicable HC standard. For a typical engine-out (i.e., untreated) exhaust gas level of2.0 grams per mile \g/mi). an overall caralyst system efficiency ofabout**92~o** is needed to meet the TLE\' HC standard at 100.000 miles vvhile an efficienc\ of88% would cause an increase in emissions to 

# i.5 times the standard (generally. the pomt

### ~t**\~·hich** the 080-fi malfunction light is required to illuminate). Such a drop in efficiency \\·auld be difficult to detect using the correlation

8.between oxygen storage and hydrocarbon efficiency with respect to the whole catalyst system. However. through monitoring ofthe front catalyst only. the timely detection ofdeterioration
can be achieved.

This approach per:mits reliable detection ofsmall but crucial decreases in overall catalyst system effi.ciency for low-emission vehicles by monitoring the front catalvst for a relatively large loss in conversion efficiency. In multiple catalyst exhaust**config~rations,** downstream catalysts tend to increase in efficiency as more hydrocarbonspass through the deteriorated front catalyst and, therefore, minimize the increase in tailpipe emissions resulting from the deterioration. The strategypresumes that unmonitored downstream catalysts are normally aged, which is reasonable considering that front catalysts are most susceptible to· deterioration.2 Therefore, a monitoring strategy thatlooks for a significant loss ofthe front catalyst conversion efficiency would be able to reliably detect a smaller loss in overall catalyst systemperformance as early as possible (it should be noted that even ifdO\'mStream catalysts

were deteriorated as well, front catalyst substrates alone are usually more than 90% efficient,

so that replacement ofjustthe front catalyst would restore most ofthe overall system conversion capability. In addition, front catalysts are often housed with a second do·wnstream substrate, so that the replacement ofa deteriorated front catalyst could include the second catalyst as part ofareplacement assembly). The staffestimated that a 50-60 percent conversion efficiency ofthe front catalyst would generally**~esult** in tailpipe emissions ofless than 2timesthe HC emission standard; however, the actual emission level does depend onthe configuration ofthe catalyst system as well as catalyst volume and composition.

Some manufacturers, however, have expressed concern overwhatthey feel is a weak correlation between oxygen storage and catalyst HC conversion efficiency for front catalysts located close to the engine. They contend that sintering ofthe precious metals in the catalyst due to excessive temperatures can lead to decreased oxygen storage apparently without a significant decrease in HC conversion efficiency, th.us increasing the chance for illumination ofthe malfunction indicator light when the HC conversion efficiency is stii(high. However, recent improvements in catalyst washcoat techno}ogy including recently developed high temperature resistant palladium-only catalysts appear to h2ve improved the correlation between HC conversion efficiency and oxygen storage, p2.tticularly in the 75% to 95% efficiency range.3

Another concern that has been expressed**regardin~** the catalyst monitoring

2Front catalystsreach higher operating temperatures L1an dov:nstream catalysts due to being closest to the engine's exhaust manifold and**becaus~** ofthe heat generated in the oxidation ofa high percentage ofthe engine out pollutants.

3 Palladium-only catalysts \Vith high**temper~ture** resis:.:mt washcoats ha\·e been presented in Society ofAutomotive Engineers (SAE) papers by**.--\lli~d** Signal Inc. (S.-\E 930386) and Ford/EnglehardlJohnson Matthey (SAE 94!058).

9.,, '

requirements for low-emissionvehicles is that front catalysts may be too small to have enou!!h



### . 

# - oxygen storage for reliable monitoring, even when the catalyst is new. Some manufacturers have stated that catalvsts need to be at least 0.4 to 0.7 liters in volume in order for catalvst
' 

### . 

## . monitoring to be reliable.

However. despite these concerns, manufacturers have certified vehicles meeting the catalyst monitoring requirements·for low-emission vehicles. The monitored catalysts use platinum/rhodium formulations with conventional washcoattechnology. One such application

uses front catalyststhat are only 0.25 liters in volume. Nonetheless, the staffis proposing catalyst monitoringrequirement amendments that should address the above stated concerns while providing for uniform and timely detection ofcatalyst system malfunctions.

Prooosed Monitorin£ Reauirement Amendments

The staffproposes to remove the requirement for the independent evaluation offront catalyst efficiency, and to instead require a catalyst system monitoring requirement in which the malfunctioncriteria will be based on tailpipe emissionlevels (similarin conceptto the monitoring requirements for non-low-emission vehicles). The staffbelievesthat catalyst monitoring techniques have matured to the pointthat a system-based approach can be adopted for low-emission vehicles without having to specify a tailpipe malfunction criteriathatin

some instances would be many times the vehicle's emission standards. A system-based requirement satisfies manufacturers' requests for more flexibility in catalyst system monitoring, and would betterensure that malfunctions will be appropriately detected in all catalyst configurations (i.e., the effectiveness oftherequirements would no longer depend significantly onthe·design ofthe catalyst system). Specifically,the staffsproposal would require the manufacturerto monitor the catalyst system suchthat a malfunction is determined before tailpipe HC emissions exceed 1.5 times the applicable standard.

To satisfy the proposed requirement, manufacturers would.determine an appropriate portion ofoverall catalyst system volume to be monitored and,.from the measured efficiency ofthat portion, infer the overall catalyst system efficiencyto determine ifthe emission threshold has been exceeded.4 Therefore, manufacturers could maintain a front catalyst monitoring strategy ifdesired, but would have the flexibility to monitor a dovvnstream cau!lyst

4 The staffsproposal also requires the OBDII system to indicate a malfunction when the NMHC conversion efficiency ofthe monitored portion ofthe catalyst system falls below50 percent. The staffbelieves that in the vast majority ofcases, compliance with the emission threshold malfunction criteria ,.,-j]] require illumination ofthe malfunction indicator light at a significantly higher efficiency; however, the incJusion ofthis requirement is considered important as a backstop to ensure that a reasonable portion ofthe catalyst system will be mon.itored.

10.in combination with the front catalyst, or to monitor the entire volume ofthe catalyst system.5

The proposed changes to the regulation would also eliminate the potential undesirable situation where

### a manufacturer.can meet the TLEV emission standard with a single catalyst substrate, and by the provisions in the current OBD II regulation would not be required to indicate a**m~lfunction** until the HC conversion efficiency ofthe single catalyst dropped to a 50-60% level. With a typical engine-out rawHC emission level of2.0 g/mi, a vehicle certified to the TLEV standards (0.125 g/mi HC) with a single catalyst substrate would not indicate a malfunction until emissions increased to-0.8 g/mi, about 6.5 times the emission standard. The staffdid not envision several years ago that TLEV standards could be met reliably with a single substrate catalyst but manufacturershave revealed several models for which such a catalyst system is planned. With the amendments proposed, the OBD II system

on all vehicles, regardless ofcatalyst system design, would be required to illuminate the malfunction indicator light at a consistenttailpipe emission level.

Feasibilitv ofthe Proposed Amendments

As part ofits investigation into tl_le feasibility ofthe proposed requirement, the staff has conducted limited testing on a 1990 Buick LeSabre equipped with a 3.8 liter, V-6 engine that has been modified to bea prototype ULEV. This vehicle achieves a baseline NonMethane Hydrocarbon (NMHC) emissionvalue of0.035 g/mi (the ULEV standard is 0.040 g/mi Non-Methane Organic Gas).6 The Buick.is configured with a 0.45 liter electrically heated catalyst (EHC) combined with a non-heated light-offsubstrate as a front catalyst, followed downstream by two 1.4 liter catalysts in a singlecontainer (see Figure 3). Preliminarytest results showthat the EHC/light-offcombination achieves an average FTP total HC aonversion efficiency ofapproximately 92 percent. Testing was then conducted with the 0.45 liter EHC/light-offcatalyst combination removed and replaced with a 0.2 liter conventional catalyst to simulate a loss ofconversion efficiency across the monitored front catalyst. HC conversion efficiency across the 0.2 liter catalyst·was measured at approximately 80 percent, resulting in a tailpipe emission level of0.060 g/mi NMHC. Thus, even with a relatively large (approximately 12 percent) drop in front catalyst efficiency over the front catalyst. tailpipe emissions did not exceed 

### 1.5 times the HC standard. This indicates that if

< Using the oxygen storage method for catalyst monitoring, it still a_ppears that compliance with these proposed requirements would be very difficult ifthe entire catalyst system is evaluated; however, some manufacturers are examining on-board HC concentration sensor concepts in place ofusing oxygen sensor information. Ifthis technology develops sufficiently, the sensor could-be most.effective when placed downstream of.the enti!e catal;'st svstem.

"To simplify testing. emissions were meas1.4red in ter;.;s of

### 1\JMHC even though the 

### LcmEmission Vehicle standards are based on**~on-\1ethane** 0:-pnic Gas**(~\10G)** Hcme,·er. for gasoline 'ehicles.**~\fHC** and "\:::-dOG emissions are near::. identical.

II.''

the volume ofthe front catalyst is sized properly, a sufficiently large decrease in its conversion efficiency can be used as the basis for identifying a fault before tailpipe emissions would exceed.the I.5 times the standard emission threshold.7 It should be noted that pwduction ULEV's are likely-to be certified with emission levels below0.03 g/mi NMHC in orderto provide an adequate in-use margin with respect to the emission standard. With ·optimized production catalyst systems, a greater loss in HC efficiency would probably be

tolerable before emissions would exceed 1.5 times the standard.



### FIGURE3

1990 Buick LeSabre

EHC/Light-off Underfloor Combination dual_substrate 0.45 Liters 1.4L1ter

1 1 . persubstrate "'--,, 

## ,....../ ,.......---· 1(Jr, I "'---...-..___>,

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# . . Efficiency

Underfloor dualsubstrate 1.4Liter persubstrate 0.035 NMHC

Tailpipe Emissions

0.060 NMHC

The staffs testing illustrates that by appropriating the right amount ofcatalyst volume in the front. monitored catalyst, manufacturers can identify a fault when its conversion efficiency drops significantly (e.g., in the 90% to 75% region, where catalyst monitoring is sufficiently reliable) yet tailpipe emissions are still relati\·ely low. As the graph provided by Ford shows (figure 4), new washcoats exhibit an improved relationship between oxygen storage and HC conversion efficiency, resulting in significantly more reliable catalyst

- monitoring. In the range from 75% to 95%

### HCconversionefficiency, the correlation between oxygen storage and conversion efficiency is fairJy linear, resulting in a reliable .separation between a good catalyst and a ba_d one

..By using this relationship, manufacturers

- The overall catalyst system conversion efliciency dropped by only 1.2 percem \from 97.9 percem to 96.7 percent) even th'rough the front catalyst active surface area was reduced by over 50 percent.

12..0.90i=0.8Iu0.7._Fi:,e4FTPCATALYSTMONITORCAPABILITYFOR76Cu.ln.PURdCATALYST·•CURRENTWASHCOATTECHNOLOGYAADVANCEDWASHCOATTECHNOLOGYNWC32hr.@1200C0.6Bhr.@1300C16hr.@1200C><w0z0.532hr.@1200c.w(!)0.432hr.@1200C0._II)0.393%LEVzwClS<0.200%ULEV0100K0.104KIII_I,------II0102030405060708090100'THRESHOLDSASSUME2GRAMSHCFEEDGASFTP-%HCEFFICIENCY•NWC=NOWASHCOAT,NOPRECIOUSMETAL,BARESUBSTRATE'THERMALLYAGED,HRS.@TEMP.7/25/94'I



### can size the front catalyst such that a monitorable decrease in efficiency results in the desired tailpipe emission threshold.
Impact**o~**

### Amendments on Catalvst Svstem Desig:n

In optimizingcatalyst systems to meet the previous OBD-IJ regulatory requirements and the LowEmission Vehicle standards, manufacturers generally are adopting configurations that utilize single ormuhiple catalysts in a close-coupled location. In some cases, the total volume ofthese catalysts could be eithertoo small ortoo large to reliably monitor for an increase of 1.5 times the HC emission standard at the tailpipe. Ifthe front catalyst is too small, a malfunction could be indicated beforetailpipe emissions reach the proposed threshold. Ifthe volume ofthe front monitored catalyst is too large, a malfunction might not be indicated until tailpipe emissions have exceeded the proposed threshold.

For instance, in several cases manufacturers are planning to place.a single substrate catalyst inthe front catalyst position. Byplacing an oxygen sensor downstream ofthe catalyst and monitoringit alone, as discussed previously, manufacturers can infer an overall system**effici~ncy** 

### without directly measuring the efficiency ofthe dov.;nstream catalyst(s). In most cases, no modifications to this configuration should be necessary to meetthe proposed change to the regulation. However, ifthe front catalyst is too small or too large (i.e., a malfunction would be indicatedtoo early ortoo late, respectively)., manufacturers can alter catalyst size by shifting yolume from the front to rear catalysts or vice-versa. Other options that manufacturers can use to achieve a configuration that is capable ofbeing monitored to 

### the proposed emissionthreshold without affecting catalyst configuration include alterations ofthe washcoat formulation, substrate cell density, amount ofprecious metals in the catalyst, or othervariables.

In systems where the front catalyst container contains multiple substrates which in total represent a volume which is too large to monitor in accord with the proposed regulatory requirement, one possible option to manufacturers (in addition to those previously mentioned) is to place an oxygen sensor in the container between the catalyst substrates to reduce the amount ofmonitored catalyst volume. The relative sizes ofthe individual catalysts in the front container could be modified without affecting the O\·erall container size. This option \>..·ould allow catalyst systems to be adapted to meet the proposed regulatory requirement without requiring major redesign ofthe underbody ofthe \·ehicle in many cases. One manufacturer is currently pursuing this option and repons that it looks very promising v.:hile another manufacturerhas already begun implementation ofplans for a future model year that will include an oxygen sensor mounted between an EHC1ight-offcatalyst combination and a dov.:nstream catalyst that are in the.same container. ·

An example ofa catalyst container with t\vo subst::nes and a rear oxygen sensor mounted in the middle ofthe catalyst container is shO\'-TI·below in Figure 5A. Ifthe volume ofthe front catalyst is too large to reliably monitor to 

### the proposed threshold. catalyst volume

can be redistributed (fig:ure 58). Converselv. front catahst volume can be increased in a

..... .,. ' 

### .

14.similar manner, ifit is too small for reliable monitoring.



### FIGURE SA



# _____ /



### FIGURESB

/ / 

## OOO!**.---,~ ~**  L_____j

Inviewofthe above considerations, and to minimize potentially costly vehicle alterations in implementingthe proposed requirement, staffis proposing to phase-in compliance ofthe new catalyst monitoring requirement. The proposed phase-in schedule would require compliance for 40 percent ofa manufacturer's projected low-emission vehicle sales inmodel year 1998, 70 percentcompliance in model year 1999, and full compliance in model year2000. This should allow manufacturers to schedule any catalyst system changes in conjunction with their internal design changes and minimize the amount ofredesign needed.

In the interim, all vehicles certified to the TLEV standard would be required to indicate a malfunction when emissions exceeded 2.0 times the TLFV Hf' standard plus the 4000 mile emission level. All vehicles certified to the LE\' standard would be required to indicate a malfunction at a slightly lower threshold, specifically, 2.5 times the LEV HC standard plusthe 4000 mile emission level. These higher interim malfunction criteria should enahle manufacturersto implement a monitoring strategy which allows them to monitor most

or all ofthe total catalyst volumeTeliably until systems configured to meet the proposed requirement can be designed

.



### . With the improvements in washcoat and catalyst technolog:- and the numher 0f**onti0n~** that manufacturers ha'e to meet the ne\\ regulation (i.e

..**::Jiustin~** CJ.tal:st \**~'lumes.** ceil density, washcoat formulations. precious metal**concemr;:.::~,ns.** locJ.ting an oxygen sensor ir. the catalyst container. etc.). the changes to the regulation 5huuld provide a means for all

15.manufacturersto comply within the allotted timeframe. However, as with previous sections ofthis regulation, staffwill continue to monitor industry's progress towards compliance with these requirements and plans to revisit the issue in 1996 to determine ifany mid-course co.rrections are needed.

EVAPORATIVE SYSTEM LEAK DETECTION

BackQround

As exhaust emissions are controlled to the maximum extent feasible for California vehicles, evaporative HC emissions become a greater**~elative**·contributorto the ozoneproblem than exhaust emissions. Compared to a ULEV, for example, which mustemit no morethan 0.040 g/mi ofexhaust HC, evaporative emissions from vehicles meeting the high temperature evaporative emission standards could be as much as 0.077 g/mi (assumihg 2.grams pertest HC emissions and using a 26 mile-per-day.average trip length). In addition, 0.05 g/mi running loss emissions (evaporative emissions generated during vehicle operation) are permitted. Clearly, since·they could exceed exhaust emissions, the strictcontrol of evaporative emissions in-use is very importantto attainment ofthe National Ambient Air Quality or state health-based standards in many areas ofCalifornia.
Fortunately, the control ofevaporative emissions is not as difficult, perhaps, as exhaust emissions, since the control hardware is comparatively simple. Further, vehiclemanufacturers have beenupgrading materials and minimizing leak sourcesto ensurethatthese systems perform reliably for many years. Unlikeexhaustemissioncontrols, however, where small amounts ofsystem or componentdeterioration can be correctedthrough adaptive learning strategies in orderto maintain the needed low-emission levels, even a very small leak in an evaporative system can lead to a gross-emitting vehicle. Datafrom General Motors, for example, shows that during a high temperature evaporative emissiontest, an evaporative system leak equivalent to a 0.020 inch diameterorifice or larger can yield about 35 grams per test (figure 6). Data from othermanufacturers is similar.8 This is equivalent on averageto about 1.35 g/mi HC, or over 30 times the allowable exhaust HC emissions for a ULEV. Realizing the importance ofleak-free evaporative control systems, the OBD-11 regulation currently requires monitoring for leaks equivalent in magnitude to an orifice as small as 0.040 inches in diameter. When the Board adopted this requirement in 1991, a 0.040 inch leak appeared to be the smallest leak which could be reliably detected on a routine basis. Even achieving this level ofleak detection has not been easy, but industry has developed-both pressure and vacuum systems which now apperu: capable ofreliably meeting thecurrent requirement. These systems will begin phase-in with the 1996model year

.

.Despite this progress, the staffbelieves it is still necessary to strive to detect leaks as small as 0 020 inL:hcs in diameter it! ensure that e\apvrati\e emissions are ..::ontrolled tv ihe

' Recem additional data are discussed later in th1s secuon.

16.624DIURNALEMISSIONSVS·LEAKSIZE4565-105-65F,1990BUICKREGAL4035+30+'1E250LC>()20I1510+____L___0.0000.0200.0400.0600.080FuolCapOrlffColookSlzo(lnchos)0·Highdatapoints+Lowdatapoints,·.: 1'

..



### needed level. The obvious benefit ofsuch a requirement would be the early detection of leaks that are ofa magnitude equal orgreaterthan a 0.020 inch orifice but less than a 0.040 inch leak. The industry has questioned the existence ofsuch leaks on in-use vehicles; however, tests conducted by the ARB indicate that leaks smallerthan a 0.040 inch orifice ate like,ly present in a significant number ofvehicles on the road. ·

r 

### The staffhas been monitoring the results ofleak deteetion testing being performedbn in-use surveillance cars at the ARB laboratory overthe last several years. At this time, almost 2,000 vehicles have been**che~ked** 

### for evaporative system leaks. In an effort to determine whetherthere are significant numbers ofvehicles in the California fleet with leaks in the evaporative system ranging in size equivalentto a 0.020 to 0.040 inch orifice, the staff analyzed pressure decay data from a number ofin-use surveillanceprojects. Vehicles in the surveillance programranged from the 1970 model year (when evaporative canister systems

.were first required on California vehicles) to the 1989 model year. The ARB surveillance program vehicles were leak checked generally before noon (during the coolerhours ofthe day) andwithin 10 to 30 minutes ofarrival at the ARB laboratory, th,ereby limiting the range offuel tanktemperatures for the test sample. Vehicle evaporative systems were pressurized to 14 inches of\\'ater and monitored for the loss ofpressure"over atwo-minuteperiod to determine ifa leak was present. The staffhas analyzed the data to correlatethe pressure drop, ifany, to evaporative system leak size. The pressure drop to leak size relationship was determined based on ARB test data from four vehicles (VWJetta, Buick LeSabre, Toyota Celica, and aFord F150 truck) whose tank sizes nominallyrange from_14 to 18 gallons. Each ofthese vehicles was tested over arange ofleak sizes (0 to 0.052 inches), fuel temperatures, and fuel Reid Vapor Pressure (RVP) valuesto simulatethe range ofconditions under which the in-use surveillance vehicles may have been tested. Thepressure drops corresponding to 0.020 and 0.040 inch leaks are listed in Table 1for the range offuel RVP and temperature conditions.

In determining the criteriafor categorizing leaks on the in-use surveillance vehicles, the staffchose near worst case values based on the test vehicle data. Specifically, in determining the upper limit for a0.020 inch leak, the staffchose the lowesttwo minute · pressure yielded when such a leak was installed (11 inches ofwater), although in several cases, the pressure was 12 or more inches ofwater.9 

### In a similar manner, the staffchose the criteria for a leak greater than 0.020 inches, but less than 0.040 inches, to be 8 inches of water. Because the criteria were based on the limits ofthe test data generated using multiple vehicles under greatly varying fuel tank 

### conditions, the staffbelieves they provide for a very conservative 

### estimate ofthe number ofsmall"leaks occurring in in-use vehicles. Using these criteria, the staffcounted ·151 vehicles with leaks between 0.020 and 0.040 inches among a total of 1,936 vehicles (7.8 percent).

9 

### The criteria were rounded to the nearest in'ch, which is the format in which the in-use surveillance data was recorded.

18.Table 1

Vehicle Initial Fuel RVP (psi) 2 min Press. 2 min Press. 2 min Press. Temp (F) for No Leak for 0.020 in for 0.040 in (in H20)"· leak (in H20) leak (in H20)
'9I VWJetta. 77 9.0 I3.8 I0.5 3.1 I I 8 9.0 I2.6 I2.8 5.9 8I 7.8 I3.I 10.6 2.8 102 7.8 13.0 I1.2 4.7
'90 BuickLe 76 9.0 I4.0 I2.0 5.0 Sabre 78 7.8 I3.7 12.0 5.3 95 7.8 I3.3 12.3. 5.5
'90 Toyota 73 9.0 14.0 I1.2 2.5 • Celica 76 7.8 I3.7 10.9 2.1 126 7.8 14.9 11.7 3.5
'94 Ford 80 9.0 14.0 I1.I 4.3 F150 115 9.0 14.0 I2.1 7.6 76 7.8 14.0 11.5 4.2 120 7.8 12.1 I1.5 5.6

Some industry representatives who have alreadyreviewed a portion ofthe data presented have expressed concern that significant fuel cooling may have occurred onthe inuse surveillance vehicles during the two minute pressuretest, potentially causing a system with no leak to appear as a leaking system (falling fuel temperature would reduce the vapor generation and system pressure). In response to this concern, the staffrecorded the drop in fuel temperature on the four test vehicles overthe two minute period. Two test cases in particular illustrate industry's point: theJetta was tested at 118 degrees Fahrenheit and the Ford at 120 degrees. In both cases, the fuel temperature dropped by approxima\ely 2.5 degrees over the two minute no-leak test, and nearly a 2 inch drop in pressure was seen in the

case ofthe Ford (1.4 inches for the Jetta). 10 However, despite such cooling, neither pressure value fell below the staffs upper criterion of 11 inches ofwater (a 3 inch drop in pressure) that was used in determining ifa leak was present. Theref<;>re, the staffdoes not believe that

10 These high fuel**temperat~res** were generated using a heat blanket v.:hich was removed priorto conductingthe pressure. tests. Ambient temperatures were in the mid-70s for both
tests< making the difference between fuel and arvbient temperatures betv.:een approximately 40 to 45 degrees Fahren.1eit. In-use. the difference between the two temperatures is usually much less. in \\·hich case less fuel cooling would be expected.

19.a significant number ofvehicle5**we,..~** miscounted for this reason. Further, to the extent that cooling could have affected the pressure drop numbers causing vehicles without leaks to appear as ifa leak existed. it is likely that on some vehicles with a leak between the sizes ofa 0.020 to 0.040 inch orifice, the leak would have appeared to be larger for the same reason and, therefore, would not have been counted (thereby cancelling any error

..in determiningthe incidence ofleaks in this category).

In the mostrecent portion ofthe surveillancetesting program covering437 

### 1980 and

newer vehicles, with the majority ofvehicles newerthan 

### 1985 (or less than 

### 10 years old), the survey results were a little betterthan the overall results, as would be expected. Vehicles with leaks equivalentto between 0.020 to 0.040 inches still comprised 3.7 percent ofthe sample (16 vehicles). Forleaks greater than a 0.040 inch or:ifice, 23 vehicles (5.3 percent)

were identified. As these vehicles age further, these percentages will undoubtedly increase. Given the relatively older, high mileage proportion ofvehicles in California, evaporativ.e system leaks are likely to occuron a significantportion ofvehicles.

There are·several factors which can affect evaporative system integrity such ·as improper orincomplete vehicle repairs after collisions im·olving evaporative system components, removal ofengines or other powertrain components for rebuilding (which can require at leastpartial·disassembly ofevaporative system components), use ofdeteriorated v.Tecking yard components on older vehicles, and manufacturingproblems. Regarding the latter, recent news articleshavebeen published describing the recall oflate model Chrysler and General. Motors trucks for fuel tank leak problems that occurred as a result ofimproper vehicle construction.11 In one instance, cracked fuel tank gaskets were found thatreportedly

werethe result ofovertightened fuel pump assemblies, and in the other, itwas found that leakage could'resultfrom improperfuel filler neck construction. In addition, vehicle manufacturers are planning on installing an evaporative system service portto allow access for checking the evaporative system for leaks without otherwise disturbingthe system.I:! The port consists ofa valve similarto those used in automotive tires which can also leak after many years ofservice. Although a tethered cap would be included with the valve, it may not always be reinstalled after service, which would permit dirt to accumulate and may eventually

cause the valve to stick or otherwise not seat completely. In addition, the service port would have 2 or 3 vapor lines connected to 

### it. which each pose an additional integrity concern. Therefore, while such a port would be useful, it is also another potential source ofsmall leaks which would contribute to the need to monitor for them

.

.11 Wall Street·Joumal, August 25, 1994. and Automotive News, January 31, 1994

1" The service port would facilitate access.in checkingthe evaporative system for leaks in

an Inspection/Maintenance program, or for pressurizing the system·for the purpose of diagnosing the location ofa leak. Presently. sop1e evaporative systems are very difficult to

access and breaking into an e\;aporative system might induce faults by disturbing aged components or through failure to reconnect some ofthe lines.

20. ., IIt is likely that smal_l leaks grovi into larger leaks in situations where**vapo~** lines age and start cracking, orwhen components are mishandled or eventually fatigue due to cycling, weathering, orother aging effects. While complete breakage offittings ordisconnection of vapor lines couldresult in leaks greater in size than a 0.040 inch orifice, gradual deterioration in evaporative system components seemsplausible. Leaks in the service port could start small

as well.

Given the estimated percentage ofvehicles'with small leaks, there is little choice but to pursue detection of.leaks at least as small as a 0.020 inch orifice. To illustrate the magnitude ofthe problem in terms offleet average HC emissions, ifthe 2003 fleet average requirement of0.062 g/mi HC is adjusted for allowable evaporative emissions, fleet average HC emissions could (as indicated earlier) be as high as 0.189 g/mi. If, as the staffs data suggest, 7.8 percent ofthe vehicles contained an evaporative leak between 0.020 to 0.040 inches, the fleet average would rise to 0.288 g/mi, 

### overa 50percent increase (see Figure 7).



### FIGURE 7



### The Effectof High Evaporative Emissions onthe MY2003 CaliforniaLight-DutyVehicle Fleet

- 0.3

### ~ Ul c 0 u; Ul E w (!) 0**~** 

### z

O.CE

Exhaust Only Exhausr

... Evap Ex,..,aus: wi? 8% small leaks

The staffhas very recentiy received data suggesting :hat evaporative emission increases due to small system leaks could be significantly less'thc.n**L~.e** 35 grams pertest previously reported by manufacturers. Apparently, with a new eV2.porc.tive system design, the majori!)' offuel vapor generated can be captured under most conditions in the charcoal canister even if

a leak is present in, for example, the fuel tank or the fuel f:Iler neck. 

### The data suggest that the resulting evaporative emission increases could be as low as 3 grams pertest. 'While this is

an encouraging improvement, it is not at all clearthat all f1.::ure vehicles w!ll perfonn similarly. From the data presented to the staff, it appea:-s 1::2.t the emission impact ofa leak depends greatly on subtle evaporative system desi,gn variati::':1S. Further. e\·en at 3·grams per

21.

### test. based on 

### 26 miles per.day (on average) ofvehicle operation, emissions from a vehicle would increase by the equivalent ofapproximately 0.115 grams permile, which is almost three times the ULEV emission standards. Therefore, relative to future emission standards. the emission benefit ofha:ving such leaks detected and repaired is still significant.

Proposed Amendment

The staffproposes to phase-in the requirement to detectleaks as small as a 0.020 inch orifice. The phase-in would begin with the 1998 model year. Fifty percentofmanufacturers' projected sales would need to comply with the requirement. This would increase to 75 percent for the 1999 model year, with 100 percent implementation required with the 2000 model vear.

The amendments would permit a manufacturerto more narrowly specifythe monitoring conditions when checking for a 0.020 inch leak providedthat the monitoring system will function with reasonable frequency in-use (e.g., a few times a week), and provided the diagnostic system will check for 0.040 inch leaksroutinely. This would permit manufacturers, should it be necessary, to better address in-use variability concerns associated with detecting smaller leaks that could, for example, leadto tpe false detection ofevaporative system malfunctions.

Feasibilitv ofthe Reauirement

In orderto satisfy the current_requirement to detect leaks equivalentto or greaterthan

a 0.040 inch orifice, manufacturers are implementing strategiesto eithercreate a vacuum or pressure condition v.1thin the evaporative system. Oncethe condition is created, the evaporative system is sealed by closing the purge valve and the fresh airvent. Ifa significant change in pressure occurs during a subsequent short period oftime (generally 15 to 30 seconds), it is assumed that a leak is present. Ifthe pressure orvacuum is essentially maintained in the system, the diagnostic system concludes that the system is leak-free.

Based on recent data obtained by the staff,**detecti~g** 

### leaks as small as a 0.020 inch orifice appears feasible. At this time. the capability ofpressure based systems to detect small leaks appears to be greater than that ofvacuum-based systems; however, data generated by the ARB staffindicate that capability adequate to satisfy the requirement should also**ex~st** 

### for the vacuum-based systems. ·

The staffstesting was conducted on the four testvehicles previously identified. The fuel tank volumes for each vehicle are 18 gallons for the Buick LeSabre and the Ford F150 truck. 14 

### £allons for the Volkswa£en Jetta, and 16 gallons for the Tovota Celica. Testing was ·

' 

# - - -

. 

# - conducted generally during vehicle cruise conditions (approximately 40-50 miles per hour on
a city street). with some ofthe tests conducted at 

### idle. Tne fuel tanks were 60 percent filled \\·ith California Phase-II gasoline with an RVP of7.0 psi. Tests were conducted for a no-leak

22.condition, a 0.020 inch orifice leak, and a 0.040 inch orifice**I~ak.** The testing sequence included sealing ofthe evaporative system under the normal operating conditions and recording the rise in pressure in the system d1:1e to vaporgeneration from the fuel for each of the leak scenarios. The evaporative system was then evacuated to about 7 inches ofwater and sealed (except for the imp!

### ante~ leaks). The rise in pressure in the system was then recorded at I0 second intervals up to 80 seconds. These tests were conducted five times for each condition. Plots were then prepared showing the net leak rate due to the presence ofa leak by adjusting the leak rate observed during the vacuum test for the.pressure build up noted when the evaporative system was sealed, but not evacuated. Theresults for the Buick LeSabre are shown in Figure 8. Plots for the othertest vehicles are included in Appendix B.

From the figures, it appears that adequate separation between the no leak case and the 0.020 inch orifice does exist. Itis recognized that additional variability may be present with a large number of.production vehicles. In examining criteriaused by some manufacturers in determining the presence ofa 0.040 inch orifice leak, it was learned that detecting a rise in pressure within a 15 second interval was a typical criterion. .Looking,at the results oftesting conducted by the ARB, it appears that achieving a similarchange in pressure for the l5 second period for a 0.040 inch leak cbuld be seen after about 60 seconds for a 0.020 inch leak, as might be projected since the area ofa 0.040 inch diameter leak is four timesthe area ofa 0.020 inch diameter leak. Therefore, by lengtheningthe monitoring period, sufficient separation appears obtainable. Figure 9 illustrates tflis point for the Buick. Normal distributions were constructed ba.Sed on the averages and standard deviations calculated for the test data with respect to specific time intervals.

Consistent with"the indications from vehicle manufacturers, the staffs assessment based on the testing is that the check will be mostreliable**in~use** under conditions oflow vapor generation. Such conditions should be encounteredoften. PhaseII fuel with a 7.0 psi RVP will be sold exclusively in California beginning with the 1996 model year,.and fuel temperatures lower than 80 degrees Fahrenheit would be encountered routinelyd·uring all but the hottest months ofthe year (even during the summer, such temperatures would generally"be encountered during morning or evening vehicle operation). Therefore, manufacturers are expected to be able to implement monitoring strategiesthat will operate reliably in-use with adequate frequency. The staffs proposal allows manufacturers to appropriately restrict monitorim2. conditions. even ifthe check is not alwavs run during an FTP test (the upper**~** 

### . ambient temperature limit for the FTP is 86 degrees Fahrenheit). Ifin-use a vehicle is filled with a hi£her RVP fuel. or iffor other reasons vapor generation is higherthan expected, OBD II

### system~ should not be subject to falsely detecting a malfunction because thefirst stage of the monitoring strategy will provide a direct indication ofthe magnitude ofvapor**generation~** Should it be unacceptably high, the check could simply be disabled until appropriate conditions are encountered.

23.8.07.06.05.00N\:r:sE4.0::J::JuC1J>3.02.01.00.0Figure8BuickLeSabre-PhaseII-60-%Fill-FuelTemp64-88F·-----·-_---o--·---.,_-------=----=-.>•------'->-,,'-,_--·---------------.---.-"'--------..'L'>"-._--...__••'--'---....'·,......._:'\\'<::::-,,_.........---·0---------6--___\'\'.,_',-------,__.,_.------,.1-1020.-...::''"+"'"".·+.---.-----13040Time(s)--050607080noleak-1-•----noleak-3noleak-4--•-noleak-5(idle)-&---.0.02in-1-•-0.02in-2•---0.02in-40.02in-5(idle)-·-1-+-0.04in·-1-----0.04in-20.04in-3-•---0:04in-4-r.i----0.04in-5(idle)Datatakenduringvehiclecruise(unlessotherwisenoted)·•9uick LeSabre

>-


# - "' c:: Ill 

### c
>- 

# i(l Figure 9 Fuel Temp Range 64-88 F

10 seconds



# .. Phase II Gas

0 V 00**~ ~**  N V**~ ~** **~** V V 00**~ ~** **~** 0 0 N N M M**~** V**~ ~** 

>- 

# - 'iii c:: Ill 

### c
>-



### == 

## :.c ttl .0 0



### ... C... I

0

>-.



# - 'iii c:: Ill c
> 

# - :.c ttl .0 0 tl: v 0 Vacuum bleedup (inches H20)

30 Seconds

I

N V
N 00 N '

# . . .

Vacuum Bleedup (inches H20)



### 60 Seconds

. - 

### ----

### - --

### -- -**--~-----------~'-----** o <:r ro N 0 0**~ ~**  N <:r ro**~ ~**  <:r**~ ~** **~ ~** **~**

. N N M M "'" "'"**~ ~** 

Vacuum Bleedup (inches H20) 60% Fuel Fill

----no Leak

0.020 in leak

0.040 in leak

----no Leak

0.020 in leak

0.040 in leak

----no Leak

0.020 in leak

0.040 in leakOther Considerations ''

From the manufacturers' perspective there are additional issues to consider. First, they po!nt out that in-use field experience even with systems capable ofdetecting a 0.040 inch leak will not beginto accrue until after the 1996 model year. Until it is known how reliable these systems will be, they believe further constraining the check may be premature. In addition, just finding a leak does not meanthat it will be easy to diagnose and repair. Manufacturers .have developed a new leak detection device which should be capable offinding small leaks, but its successin the hands ofservice technicians is notwell**kno~.** Further, ifa leak equivalent in sizeto a 0.020 inch orifice is the result ofa combination ofeven smaller leaks, the diagnosis would be even more difficult, they maintain. However, the service industry has successfully located much smaller leaks in air conditioning systems for decades, so that detection ofleaks in evaporative systems should not prove insurmountable.

While manufacturers' concerns are understood, the staffhas concluded that pursuit of detecting smaller leaks is necessary in view ofthe potential air quality effects ofsettling for Jess. Since detection ofa smaller leak is envisioned to be done primarily by lengthening th"e

.monitoring period, perhaps further constrainingthe checking conditions, and correcting for

vapor generation, there should be no increase in hardware cost to accomplish the goal. There is also time betweennow and beginning implementation ofthe proposed 0.020 inch leak detection requirementin 1998 to reviewthe industry'sprogress: Shouldit appearthat manufacturers would have to make significanthardware changes to meetthe amended requirement, the staffcould provide for a revised phase-in ofthe requirement. Any needed alterations could be consideredby the Board in a 1996 review ofprogress in meeting OBD II requirements.

MISFIRE DETECTION

Since adoption ofthe OBD II regulation in 1989, the ARB has been seeking misfire monitoring capability which extends throughoutthe full engine operating speed and load range. At the 1991 Board review ofprogress in meeting the OBD II reql.:liremerits, it was determined that technology had not progressed sufficientlyto ensure that full-range monitoring capability could be achieved in the 1994-1996 OBD II phase-in time frame. Accordingly, the goal was moved to the 1997 model year. and industry agreed to redouble their internal efforts and include evaluation ofanumber ofindependent sources ofmisfire detection capability before the next Board review ofthe OBD II requirements.

For models introduced before the 1997 model year. the current regulation requires misfire monitoring overthe engine operating range encountered during an FTP test. The OBD II malfunction light is to illuminate whenthe level ofmisfire is.high·enough to lead to catalyst damage, cause emissions to exceed the applicable emission standards by a factor of 1.5. or to result in failure ofan Inspection/Maintenance program test. In addition, the


# .

. malfunction li£ht is to flash when misfire is occurrin2. at a rate which could lead to catalvst**~** 

# -

. damage. and remain steadily illuminated otherwise once the misfire rate exceeds the

26.applicable thresholds.

The ARB staffhas continued to seek full engine operating range monitoring capability for a number ofreasons. Engine misfire does not necessarily occur at all engine speeds and loads: sometimes misfire occurs only at high engine speeds and loads: light load part throttle operation. idle, or other isolated operating conditions. Moreover, under high speed and load conditions, for example, even small amounts ofmisfire can very quickly lead to catalyst overheating and failure. Misfire may also occurduring the cold start and warm-upperiod, which could contribute substantiallyto excess emissions, but then may subside during warm engine.operation. Evenhigh engine speed operation under light load conditions needs to be monitored since some vehicles may encounterthese conditions in mountainous terrain durin£ alternating periods ofengine braking and acceleration, or in congested traffic conditions (when owners ofmanual transmission vehicles are prone to minimize shifting and let the engine speed climb to high levels during frequent stop and go intervals). Since it is not possible to predict.the likely misfire characteristics ofolder vehicles, it is important to cover
as much ofthe full range ofengine operation as possible 

### in monitoring for misfire. From a re·gulatory implementation standpoint, the staffwould also like to avoid makingjudgment calls on the appropriate monitoring range capability for e\·ery engine certified in California, as each·engine will have different characteristics which can affect the misfire monitoring range. Ifall engines must generally meet the full range monitoring requirement, then·certification acceptance is simplified, and there would be littlepotential for inequities injudgingthe acceptabpity ofeachmanufacturer'smisfire detection capability13•

Since the last Board review, the misfire monitoring capability ofthe automobile manufacturers has steadily improved, and the capabilities ofindependentparties ih this arena have also improved. Manufacturershave generally increased their computerprocessing speed, improved their misfire detection algorithms in numerous areas including incorporation of adaptive learning compensation for irregularities in manufacture ofthe ignition signal pick-up wheels, relocated the pick-up sensor to optimum locations to minimize signal noise, improved base-engine roughness through improved fuel targeting, and other enhancements.

At this time it appears that industry will be capable ofcertifying 50 percent oftheir projected sales volumes to almost all ofthe full speed and load eng:irie operating range by the 1997 model year. Only a very small portion ofthe full er,gine operating range would need to be excluded from the full-range monitoring requirement. This is a very light load operating condition occurring above 3000 RPM where driving \Vou!G be relatively rare. The engine speeq and load region over which misfire monitoring would be required is shov.n in Figure 10. Ford Motor Company has indicated notable success in its misfire detection capability.

13There is still· some

### ~llowa;ce in the regulatory propos.1!. howe\·er. for engines with fundamental desi!:Ul limitations which hinder reliable**misfi~e** detection to**fore~o** monitoring in**~** 

## - a very narrow operating range. '

27.., I
Working with Motorola on a high data rate system which incorporatespattern recognition techniques, it appears that very high speed misfire monitoring is possible. The only drawback to the system appears to be some limitation in identifying the misfiring cylinderat high engine speeds, but this limitation is offset bythe otherwise excellentreported capability ofthe**sys~em.** Another significant benefit is that the cost ofthis adc;ied capability is expected to be surprisingly low. ·

"C Cl) 0 ...J (I) c ·c;, c w

idle 2000 

### Fig\.Jre 10

Postive Torque Load - 4 inches Hg**~**

. 

# .

3000

Engine Speed

At this time it appears that someengine and driveline characteristics still preclude reliable misfire monitoring over the full range ofoperating conditions; in particular, engines with 1 0 or I2 cylinders may yet pose a challengefor meetingthemisfiremonitoring requirements. Because these engines require further evaluation, staffis proposing to phase-in the full-range misfire monitoring requirement beginning in I997 at 50 percent ofa manufacturer's projected sales volume, 75 percent in I998, 90 percent in I999, and full compliance in :2000 (small volume manufacturers would comply in 2000). In addition to manufacturers' efforts, staffis aware that Technical Advances, Inc. 

### in conjunction with SSI Technologies, Inc, Professor Citron at Purdue University, Professor Ribbens at the University ofMichigan, Kavlico, ;\nalytical Methods, ABB Industrial Systems, and others are working to solve the misfire detection problems ofthe remaining difficult engines.

With the current proposal, then, time remains for industryto continueto improve misfire monitoring capability for the more difficult to control engines. Staffwill again evaluate progress at a review hearing in 1996 to determine ifchanges would be needed to the re!.wlation for 1998 and later model year vehicles.

28.OBD II IMPLEMENTATION ON DIESELS

In 1991. the Board adopted amendments to the regulation making the OBD II requirements applicable to diesel engines begi_nning with the 1996 model year. Recognizing**tha~** some OBD II**n!quir~ments** would.not apply, or could not be met on diesel applications, the regulation currentlyrequires manufacturers ofdiesel enginesto submit an OBD II monitoring plan for ARB review. After a number ofdiscussions with manufacturers since the time diesels were included in the OBD II regulation, the staffbelieves enough has been learned to more specifically detail the minimum monitoring requirements for diesel applications.

Generally, diesels are not equipped with evaporative systems, secondary air, or oxygen sensors. These monitoring requirements would, therefore, not apply. Regarding catalyst monitoring, the ARB staffhas not yet identified atechnology that can be put into production to detect diesel catalyst deterioration. Because diesel vehicles operate lean of stoichiometric, the principle ofoxygen storage as discussed earlier for vehicles using thre.eway catalysts could not be used_. Catalyst monitoring is notproposed'for diesels on this basis.

However, with respect to misfire monitoring theARB staffbelievesthat a fo,rm of misfire detection on diesels is feasible and would be useful inreducing in-use emissions, especially at high mileages (i.e., beyond I00,000 miles). Itis recognized that diesel engines

are not likely to develop intermittentmisfire problems as are sparkignited engines; however, malfunctions can occurthat prevent combustion in one ormore cylinders. Ifcompression is lost, the air/fuel mixture would pass through the cylinder**unburh~d,** and a large portion ofthe mixture would also pass through the catalyst (ifequipped) into the atmosphere. The staffs proposal is to require the detection ofthe complete loss ofcombustion in one ormore cylinders. The proposal would allowthe misfire detection strategy to be active only during certain operating conditions (e.g., during idle), and monitoring wouldberequired only once perdriving cycle. Implementation ofthis requirement is proposed to begin withthe 1998 model year. Manufacturers ofspark-ignited engines have been able to implement misfire detection systems based on engine speed fluctuations that are capable ofdetecting one to two percent engine misfire over a wide range ofoperating conditions. Compared with the requirements for spark ignited engines, the diesel manufacturers should be able to implement moniwring strategies to detect complete cylinder misfire under specific operating conditions using similar techniques by the 1998 model year.
Regarding fuel system monitoring, diesel engines do not employ the type ofclosedloop fuel control systems found on vehicles with three way catalysts (i.e., feedback information on exhaust composition with the use ofan oxygen sensor), although some diesel control system designs are capable ofproviding feedback regarding fuel injectorperformance. Therefore, the staffhas proposed an amendment to clarifythat diesel fuel system monitoring is required to the extent possible to detect fuel system mc.Jfunctions that would cause**t~e** vehicle or enoine to exceed 1.5 times anv ofits emission standards: hov.;ever. manufacturers e**~** . . . \\·auld not be responsible for detecting malfunctibns for which the system is incapable of

29.

### providing necessary feedback (e.g., a·fuel injector with abroken tip).

Consistent with the requirements for spark-ignited engines, manufacturers ofdiesels would also be required to implement OBD II monitoring strategies for EGR system**pe~:formance** 

### and for any electroni"c componentsthat·can affect emissions when malfunctioninQ (e.g

.. intake airheating, electronic transmission components, wait-to-start iamp, etc.).

-

1996-2000 MODEL YEAR COMPLIANCE
Compliance with the OBD II regulation requires the implementation ofa large number ofmonitoring**s~rategies.** 

### Manufacturers are required to design and work with new monitoring concepts for components and systemsthat up until now, have not been monitored

.on-board. The staffrecognizes that manufacturers face aheavy workload in bringing such

strategiesto production across their prodpct lines in a manner that will ensure that OBD II systems are effective and reliable in-use.

. 

# . The Board has recognized the difficuhy ofinitially implementing OBD II systems on vehicles. In July, 1993, the Board adopted an amendment to the regulation that provides for limited relieffrom specific requirements if, despite a good-faith effort, full OBD II compliance with the requiremenls could not be obtained. For 1994 and 1994 1/2 models, the regulation permitsthe certification ofOBD II equippedvehicles even ifone ormore monitoring strategies do notmeet the minimumrequirements oftheregulation. For 1995 models, the number ofallowed monitoring deficiencies is limited to two perengine family. If

a manufacturerhas more thantwo deficiencies on a particularengine family, the vehicle could still be certified, butfines would be applied to the third and subsequentlyidentified deficiency. The amount ofthefines is 50-dollars pervehicle per deficiency for a major monitoring system deficiency (e.g., catalystmonitoring, misfire monitoring, evaporative system leak detection, and others), and 25 dollars for deficiencies associated with monitoring systems for other electronic components.

The adoption ofthis provision has proven to be Yaluable, since despite best efforts, most manufacturers have needed to certify vehicles with deficiencies whenproblems arose which were unanticipated and which could not-be immediately resolved. It is also clear, especially for. 1995 model year vehicles, that manufacrure:-s have generally taken every reasonable step to avoid having to request use ofthe deficiency·provision due to the risk of being subject to fines for subsequent unanticipated problems.

Given the newness and complexity ofdesigning OBD II systems, it is likely that deficiencies will continue to occur as manufacturers will implement OBD II across their full product lines in 1996. Accordingly, tbe staffis recommending carry-over ofthe allowance for.two deficiencies per engine family for the 1996 mode! year. With respect to electronic transrnissions. it is possible that aparticular problem (such as the inability to incorporate a communication link between the transmission and emrine control units due to a late chanQe in

I

- - 

### the type oftransmission to be used) could prevent monitoring ofseveral. or even all

30.transmission-components subject to monitoring under the Comprehensive Component Monitoring requirements. To address this, the stafffurther proposes (for the 1996 model vear only) to count multiple transmission componentmonitoring problems as a single**deficienc~'.** Staffis convinced that manufacturers will use permitted deficiencies sparingly since most · 1996 engine families are not expected to require variances based on preliminary reviews of most manufacturers' planned systems. Although some manufacturers may need to utilize one ofthe deficiencies for some models in 1996, few are even suggesting that the**sec~nd** allowed deficiency will be required since they are saving it for an unexpected shortfall.

- Concerning post-1996 models, the changes being proposed for this hearing would continue to require innovation by manufacturersin the area ofcatalyst monitoring, misfire detection, evaporative system leak detection, and issues associated with introducing more lowemission vehicles in this timeframe. Although most ofthe othermonitors will have been developed for**th~** 1994 to 1996 model year vehicles, 1997 and later vehicles may encounter potential deficiencies in trying to meet the proposed changes to the regulation. In discussing the proposed changes for some ofthe major monitoring requirements,with manufacturers, it appeared many were willing to try hard to meet_the newproposed requirements. In return, they asked for continuing latitude in case they fall short in meeting some ofthe requirements and requested that the ARB consider some additional latitude with regard to in-use recall liability until they can gain more real world experience v.ith some ofthe newrequirements.

The staffconsiders industry'srequest to be reasonable, and is, therefore, proposing that one deficiency be permitted for each engine family for 1997through 2000 model year vehicles, although unlike previous deficiencies, completelack ofa monitorwould not be permitted without incurring a fine. This latterrequirementis important withrespect to the ARB'splans to begin evaluating the potential ofusing a check ofthe OBD II system in place ofthe current Inspection and Maintenance testing methods. The staffalsoproposesthat deficiencies occurring in the 1997 and later model years could not be carried overto the following model year unless it can be demonstrated that correction ofthe deficiency would require hardware modifications that could not be accomplished due to lead-tiil!e 9r similar issues. Further, the staffproposes that in no case could adeficiency be carried over more thanone year without a fine. This would preclude a manufacturerfrom using the proposed latitude to avoid development ofa fully complying monil·oring system for an extended period.
Regarding in-us_e compliance, the staffis proposi::g that for TLEVs. manufacturers \v·ould not besubjectto compliance.actions until emissior.s exceed 2.0 times the applicable standards through the 1998 model year for those monitors which must be designed to mee1 a 1.5 times-the**e~ission** standard threshold. LEVs and UL.EVs would have the same allowance apply through model year 2000. Further, because the cat2.lyst monitoring requirements would continue to evolve in the 1998-2000 model year**timefrarr:~** even for TLEVs, ifthe staff proposa1 is approved by the Board, the 2.0 times the emission standard threshold in-use \Vould apply to catalyst monitoring for all low-emission vehicles through model year 2000.

31.Given the stated wtllingness ofsome manufacturers to continue to strive to meet the ultin1ate.objectives ofOBD II which are now in sight, the staffconsiders the allowable deficiencyprovisions coupled with intermediate in-usecompliance latitude to be an optimum balance for promoting the bestinnovation and development from industry while ensuring that the resulting OBD II systems are as reliable and complete as possible.

OTHER PROPOSED MODIFICATIONS

In additionto the proposed modifications to the OBD 11 requirements that have already been discussed, the staffis proposing a number ofmore minor modifications. As manufacturers havebegun to place OBD 

### II systems intoproduction, the staffhas found that manufacturers have misunderstood or have been uncertain ofthe intent ofsome requirements. The proposed modifications would clarify the regulation in this respect, and would make**adju~tments** to the requirements when necessary based on the staffs experience in reviewing OBD II system designs. The more notable modifications are presented below. A full listing of yroposed amendments can be 'found in Appendix A. '

!\-tiL Illumination and Fault Code Storaee Protocol:

Section (a)(l.9): The addition ofthis section is proposed to slightly modify the requirements for the OBD 

### 11 MIL illumination and fault code storage protocol. Currently, illumination ofthe MIL is generally not required unless a malfunction is detected during two sequential trips. A trip is defined in part as a period ofdriving during which all components and systems are monitored atleast onceby the OBD II system. Therefore, if

### a specific monitoring strategy detects a malfunction in two sequential driving cycles, MIL illumination is not required unless all other (even non-related) monitoring strategies have operatedduring both ofthe driving cycles. The staffproposes to modify the protocol such that MIL _illumination would be required ifa malfunction is detected in two sequential driving cycles

.**r~gardless** ofwhether or not other monitoring systems have functioned. However.

manufacturers would still be permitted to verify the proper function ofcomponents critical to
aparticular monitoring strategy before the monitoring system operates or before the results

are validated. To allow for any OBD II system softv.·are changes necessary to incorporate the revised protocol, its implementation is not required Uiltil the 1997 model year. Other sections modified to incorporatethe proposed change: (b)(l.3.1).·(1.4.1), (2.3), (2.4), (3.4.2). (3.4.3), (3.8). (3.9), (4.3), (4.4.1), (5.3), (5.4). (6.3). (6.4), (7.4.1), (7.4.2). (7.4.3), (8.3.2), (8.3.3), (8.4), (8.5.1), (9.3), (9

. .4), (10.3.1), (10.3.2), (10.4), (c){2.2).

Misfire Monitorine Cvlinder Identification:

Section (b)(:1: 1): Currently, the regulation**requ1re~** the specific Identification ofthe misfiring cylinder during all operating conditions under \\h1ch mistire detection**~ystem~** are active. However, in \vorking towards meeting ,the expanded monitoring conditions for misfire detection that are to begin 

### with the 1997 model yeJ.r. some manufacturers have founcl that specific cylinder identification can be unreliable at h:gher engine speeds. The staff

32. 

# ..

### proposes an amendment that would permit manufacturers to request Executive Officer approval to disable algorithms employed to identify the misfiring cylinder under certain operating conditions ifit can be**demonstr~ted** 

### that the algorithm would not operate reliably when such conditions exist. This amendmentwould not affect the operating conditions uncler wh.ich misfire is to be detected. Ifmisfire is detected under a condition where the specific cylinder cannot be reliably identified, the OBD II system would be required to store a general misfire fault code.
Tamper Resistance:

Section (d): The staffhas proposed regulatory language to make more specific the requirements for making OBD II vehicle calibrations resistant to tampering. On vehicles that LJ)e Electronically Erasable Programmable Read Only Memory (EEPROM). which prov1de the capability for a vehicle to be reprogrammed electronically through its communication**link~** 

### the staff's proposal would require manufacturers to utilize reprogramming strategies that require access to a centralized computer maintained by the m'anufactu,rer as well as the use of full data encryption (scrambling ofthe software code). Equivalent strategies would also be acceptable. The staffis concerned that an incentive to tamper with OBD II system calibrations could exist should California implement an Inspection and Maintenance test based on the use ofOBD II systems, especially considering the high cost repair limits that

are likely to be part ofthe program. The success ofthis liM concept depends**gr~atly** 

### on the extent to" which OBD II system information is reliable. Implementation ofthese more sophisticated proposed measures would not be required until the 1999 

### model year in order to provide manufacturers with adequate leadtime to make necessary vehicle and reprogra(nming equipment modifications.
Apart from the Inspection/Maintenance program concerns, the staffbelieves that effective security measures are necessary to ensure the integrity of OBD II systems and engine control calibrations on vehicles using EEPROMs. With this type ofcomputer chip. vehicles can be recalibrated without physically modifying or replacing any on-board computercomponents in an attempt to enhance vehicle performance. Without tamper resistance measures, vehicles could be modified with commonly available computer equipment. Although information regarding the location ofkey engine parameters within the 'eh1cles programming would be necessary to successful!) lamper with the 'ehJcle. such Information, once learned by a few, could spread over coznputer bulletin boards and networks, for example. which are being used to a greater .:xtent within the service industry. With the staff's proposed amendments, individuals would face a much more difficult task in trying to "reverse engineer" the reprogramming protocol. Further, ifthe basic protocol is learned, the requirement to access a centralized computer would complicate the task of reprogramming on a wide scale basis, and would allow tk manufacturer to**·mo~itor** 

### reprogramming acti\'i

### ty.

It should be noted that the aftermarket**p~rts** 

### indus::-y**ha~** 

### expressed concern over tile dllti-tdlllpering**prLwi~Jon~** 

### which l1ave been present in ::1e l.lBD 

### II reguiC!tJOJl**~!nee** 

### Jt**\\d~**



## ::n.

### adopted by the Board in 1989. 

### and the proposed changes to make these provisions more specific has heightened its concern. In the past, the aftermarket industry has relied on decoding manufacturers' software to enable irto integrate replacement or specialty equipment into vehicles. The requirements ofOBD II substantially complicate their design task in that aftermarket parts must be compatible with OBD II systems to prevent inadvertent malfunction indications. With additional security provisions, the aftermarket is concerned that successfully integrating its products into vehicles equipped with O:SD II will be very difficult to accomplish.

However, it should be noted that some vehicle manufacturers will likely implement tougher security measures than currently required without the proposed modifications (in which case, the OBD II tamper resistance requirements would primarily only ensure that manufacturers remain consistent in implementing adequate security measures). This action would be taken primarily in response to recent indications from the United States Environmental Protection Agency regarding requirements for greater information availability to the aftermarket and service industries which would include the car>ability to install vehicle software calibrations. Manufacturers will want to implement additional security measure.s to
ensure that only authorized reprogramming occurs. In somecases, vehicle manufacturers already have computerdesigns which are very difficult to access. Realistically, it appears that the aftermarket parts industry will need to work with vehicle manufacturers to gain

. assistance in developing calibrations necessary for its products in a business relationship,

even in the absenceofmore specific security measures in OBD II. The ARB staffhas spoken with the vehicle manufacturers about this issue, and it

### appears that the aftermarket industry is viewed as a valuable asset in marketing certain kinds ofvehicles, so that working with them should eventually occur. Unfortunately, at the present time. vehicle manufacturers

are busy developing their full product linesto meet the OBD II requirements in the 1996 

### model year, so that sufficient dialog has not yet taken place among both parties.

Thepurpose ofthe security measures specified in OBD II.is to ensure that tampering will not reasonably occur with respect to Inspection and :-..1aintenance programs and vehicle performance. Insofar as legitimate aftermarket products manufacturers are concerned, it appears they will need to form business relationships with the vehicle manufacturers· regardless ofthe security meas[Ires being proposed for OBD II. The staffwill monitor the cJevelopments in this area and determine if

### additional**m~.sures** 

### to accommodate legitimare aftermarket parts manufacturers interests would be appropriate during the !996 

### OBD II review hearing.

Alternate Fuel Vehicles:

Section (m)(5.l): Vehicles designed to operate on·alternate fuels are currenqy required to comply with the OBD II requirements beginr.ing.with the 1996 

### model year. However, manufacturers have stated that due to 

### the worb)ad associated with complying full; with the OBD II requirements on conventional t·elliclcs**1·:~** 

### the 1996 

### model year. coupled \\'IIIl 

### ·rhc low volumes projectecl for dltcmate fuel \'chicks. 088 II de,elopment and testing with

34. •,

### respect to these vehicles cannot be completed in time for 1996 

### mode·] year implementation. 1\

### 1anufacturers have stated that more time is needed to eval·uate the edectsofa]ternate fueh

on component performance to ensure that OBD II diagnostic**str~tegies** 

### will be reliable.**in-us~**

### .

. -\s a result, manufacturers h.aw considered pulling back plans to sell alternate fuel velm:lt:·'>

111 

### l.Y'::l6 and possibly )llbsequent model years.
Recognizing manufacturers' concerns, the staffproposes to delay full OBD 11 implementation until the 1999 

### model year for alternate fuel vehicles. Between the 1996 

### and l998 

### model years, manufacturers would·be required tojmplement diagnostic strategies to the extent feasible, but would not be required to include monitoring strategies for which the effects ofalternate fuels are ofconcern. Specifically, manufacturers would be required to implement circuit continuity and functional checks at a minimum as well as unaffected major system monitors such as fuel system monitoring. or monitoring ofthe EGR valve, but could request Executive Officer approval to delay, for example. oxygen sensor response rate monitoring, orcatalyst efficiency checks until the 1999 

### model year.
Similarly, the staffproposes an amendment to California's certification procedures for alternate fuel retrofit vehicles. The proposal would provide retrofit system manufacturers

some leniency until the 1999 

### model year with respect to maintaining full operation ofOBD II monitoring strategies developed for use with gasoline. For**example~** 

### a retrofit system manufacturer would be permitted to request Executive Officer approval to disable the vehicle manufacturer'soxygen sensor response rate check, but would be-required to maintain other oxygen sensor output voltage checks that would not be affected by the use ofan alternate fuel. The proposed modifications to the procedures are included in Appendix D.

\"I. IMPACT ON COSTS. THE ENVIRONMENT, AND BUSINESS AND ECONOMY OFTHE STATE



### The proposed modifications to the OBD II regulation do not necessitate the**u~e** 

### of addi-tional monitoring hardware. The changes revise and clarify already adopted requirements and do not expand the scope ofthe regulation. To this extent, the staffdoes not expect an incremental cost per vehicle to result from ::1ese proposed modifications. 1\lanuiacturers may need to make some design modificatwns to 

### meet. for example, the revised catalyst and evaporative system monitoring requirements: however, the staffestimates that the overall OBD II development burden will decrease with the proposed amendments in comparison to the current requirements. A more detailed discussion with respect to the costs associated with th_e more significant proposed amendments is provided below.

Reoardino catalvst monitorino in manv instances, the revised malfunction criteria will b ;:::. - .:::0' "' 

### not require any suhstantive vehicle design changes. with t'le exception ofsoftware changes to
ensure that the emJSSJon thresholds will be met in-use. Hc,wever, manufacturers have Jnci!Glled that 011 '.uJne 

### Jllockh. cat<-dvst nwclifict'tion'> sue:· ;ls 

### the incorporation ofan o:--yge11**~5.**

### sensorbetween catalyst substrates in the same container will be necessary. There will be

some additional cost associated with confirming the durability ofthis revised catalystdesign. although when spread over the large numbers ofcataiysts expected in the future, the incremental cost woul9 be negligible. In.a few cases, catalysts will need to be relocated in tl1e.exhaust system to be optimized for monitoring. In order to 

### reduce tooling and development costs, the staff'sproposal for catalyst monitoring includes an interim emission threshold that will prevent the need for any such modifications untp the 1998 model year at the earliest, and**po~sibly** 

### until as late as the 2000 model year. Manufacturers, therefore, will have the opportunity to make necessary changes concurrently with othervehicle modifications. In otherinstances, the proposed modificationsprovide substantial regulatory relief. Some manufacturers have indicated that the current front catalyst monitoring requirements for low-emission vehicles cannot be practically implemented on certain !996 or 1997 model year applications without significant product design changes or the last minute development ofa new monitoring technology. With.theproposed modifications, such changes would no longer be necessary for near-term OBD II compliance.

For misfire monitoring, the proposed revisions for the .1997 and later model years
ease the burden ofOBD II compliance compared to 

### the current requirements. Manufacturers would be permitted to phase-in expanded monitoring conditions in place offull 1997 niodel year compliance. Further, the regulation would define asmall positive torque engine speed and load range where misfire detection is not required.· Both aspects ofthe staffsproposal would reduce the resources necessary for OBD II misfiredetection compliance. Regarding misfire monitoring for diesels,the requirements for these vehicles are less difficult overall t.o satisfy than those already in place for spark-ignited engines. Therefore, the staffexpects the cost ofcompliance with**~espect** 

### to diesels to 

### be less**th~n** 

### that for spark-ignited engines.
Regarding evaporative system monitoring, as discussed previously, it appears that manufacturers will be able to incorporate a method to detect leaks equivalent to a0.020 inch orifice through software modifications. These modifications should not have a significant impact in terms ofcost per·vehicle

The last proposed modification that could significantly impact the cost ofOBD II compliance is the incorporation ofprovisions for OBD II 

### certification with deficiencies beginning with the 1996 model year and extending through the 2000 model year. These provisions permit the certification ofOBD II systems even though one.or more monitoring system deficiencies have been identified. Fines of25 to 

### 50 dollars per deficiency p.er vehicle would apply to the third.and subsequentdeficiency identiried in a 1996 model year engine family, and to the second and subsequent deficiency for 1997 through 2000 model year vehicles. Despite the proposed fines, use ofthe provision will resultin a net cost savings,to the manufacturer in that the regulation does not currently allow certification ofvehicles with monitoring system deficiencies after the 1995 model year. The cost to the manufacturer and affected California businesses ofhaving to remove developed product from the California marketplace would almost certainly far exceed c\ny fine that may apply.

36.

### The Environment

Many ofthe proposed modifications to the OBD li 

### regulation are intended to clarifv the monitoring requirements and to make minor regulatory adjustments based on the recent experience obtained in certifying OBD II compliant vehicles. As. a result, these changes should simplify the task ofunderstanding and implementing the OBD II 

### requirements, and

are not expected to significantly affect the performance qf

### OBD II systems in-use or have any adverse impact on the environment. More significant amendments are proposed for catalyst monitoring, misfire monitoring, and evaporative system leak detection. Whilein some instances the requirements would berelaxed slightlyin the nearterm, the staffbelieves overall that the modifications proposed will provide for greateremission reductions from California's OBD II program.

For catalyst monitoring on low-emission vehicle applications, it is difficult to compare the impact on emissions resulting from the proposed system-based requirements relative to the current front catalyst monitoring requirements. As stated previously, the tailpipe emission level ofa vehicle when the front catalyst has deteriorated td

### the malfunction criteria depends significantly on the design ofthe catalyst system as a whole. In some instances it is clear that a front catalyst monitoring strategy would illuminate the MIL beforethe proposed interim system-based malfunction criteria would be exceeded; however, in otherinstances (particularly when only onecatalyst substrateis located in the exhaust stream), such a monitoring strategy could illuminate the MILat a 

### HC emission level many times theinterim criteria. Once the phase-in ofthe 1.5 times the standard emission threshold is complete, catalyst monitoring systems should in all casesbeequallyor more effectivein achieving**emis~ion** 

### reductions in-use than systems developed to meet the current requirements.
Regarding the OBD II misfire monitoring requirements,·the staffhas proposed additional leadtime for meeting the expanded misfire monitoring conditions through the use ofa 4 year phase-in, and has defined a small region ofpositi:ve torque operation wherein misfire detection disablement would be permitted. As such, a significant percentage of vehicles in the 1997 

### to 2000 model year time-frame would have misfire detection systems that are operational over a significantly smallerportion ofthe engine operating range in comparison to the current requirements for the I997 

### and later model years. However, in ;ullov:mg the progress ofmanufacturers towards meeting the current requirements. the staff Dclieve<, it IS 

### likely that a number ofmanufacturers will r.ot be able to meet the current requirements on all engine families. Consequently. shouid the staffs proposal not be adopted. many vehicle manufacturers would not receive certification for some engin.e families after the 1996 

### model year. It is the staff's determination that the exclusion ofvehicles from the California market would have an adverse economic ir:1pact on California businesses (including dealerships, automotive suppliers, and servicecenters) that would be proportionately greater than any resulting'negative irhpact on the environment. The reduced availability ofvehicles would also likely translate into higher consumer costs for new vehicle rurdlases. As such. the staffbelieves that overriding economic considerations exist that on balance outweigh the potential increase in emiss'ions**resu~:ing** 

### from the phase-in ofthe

. 37.

### misfire detection requirements.

Foralternate fuel vehicles, the staffsproposal would allow manufacturers to delay the implementation ofsome monitoring strategies until the 1999 model year. The staff believes that any negative impact on emissions would be minor since manufacturers' projected sales volume for aiternate fuel vehicles arevery low. Further, manufacturers indicatethat their alternate fuel engine families will generallybe desigl)ed to meet LowEmission Yehicle.standards (the only currentlycertified ULEV model operates on compressed natural gas). It is expected, therefore, that fleet average emissions from alternate fuel vehicles will be lowerthan the fleet average emissions ofgasoline powered vehiCles in the 1996 through I998 timeframe. Accordingly, any negative emission impact would be somewhat mitigated, since both vehicle manufacturers and retrofit system manufacturers are likely to pull back alternate.fuel vehicle plans should full OBD II compliance continue to be required with the 199n model year. Regarding t.he provision for the certification ofOBD II systems through the 2000 model year with system deficiencies, it is likely that any negative impact on emissions would be small from the certification ofsuch systems. This is because the number ofpermitted defic,iencies is limited, and basic monitoring capabilities must be implemented for every monitoring req.uirement after the·l996 model year, even though the monitor may fall short of the complete regulatory requirement. In addition, manufacturers would avoid use ofthe deficiency provisions to guard against unanticipated problems which would require their use in orderto avoid afine situation. Thesepointsarediscussed in greaterdetail in section III ofthis report. As with theproposed misfire monitoring amendments, intheabsence ofsuch provisions, thepossibility ofvehicles being excluded from the California market would be significantly greater, resulting in an overriding negative impact on the economy'of California.

Finaily, with respect to the evaporative system monitoring**requirem~nt** 

### amendments.

as previously discussed, the enhanced requirement should result in a significant reduction in evaporative emissions to the extent that small leaks occurin-use with new evaporative system designs. Based on available information, the staffbelievesthe emission benefits from these reN'isions should more than compensate for any negative.impact on the environment associated with the staff's proposals fm misfire monitoring, alternate fuel vehicles, and 1996 through 2000 model year compliance.

Business and Economv ofthe State ofCalifornia

The modifications proposed by the staffshould not, in general, have any significant impact on the economy ofCalifornia, or employment orbusiness within the state. The OBD II requirements are directed at manufacturers ofnew motor vehicles, nearly all ofwhich are located outside ofthe state. As discussed above, the proposed modifications should ensure that**m~nufacturers** 

### will be able to keep current product plans intact throughout the early years ofOBD·11 Implementation in California. This wili prevent any disruption WJtllJn the:

38.

### California businesses associated with the automotive**indu~try.**


### However. the requirements may have a significant adverse impact on businesses which design and produce aftermarket components and systems for light- and medium-duty vehicles. As mentioned previously, the potential exists for increased development and proauction costs associated with having to certify that aftermarket parts will not adversely affect the performance oforiginal equipment OBD II monitoring strategies. Nevertheless, the proposed amendments should not adversely affect ability ofCalifornia businesses to compete with businesses outside the state in that all aftermarket parts producers must obtain certification in orderto sell theirproducts for use on California vehicles.

Conclusion

After several years ofdevelopment and discussion. OBD II**system~** 

### h;we become a reality in California. Monitoring systein concepts have gone from the draw1ng board 1nto production on more than 35 engine families already, with many more to follow. The regulatory amendments proposed by the staffwould help in the**proce~s** 

### ofreviev.·if!g and certifying manufacturers' systems by clarifying requirements, and by making minor adjustments to the regulation based on the valuable experience gained to date. Further. the staff's proposal would maximize the long-term effectiveness ofthe OBD II program by restructuring and enhancing current monitoring requirements based on the latest improvements in monitoring technologies. However, at the same time, amendments are proposed that would ease the burden manufacturers face in implementing OBD II systems by addressing a number oftechnical and practical concerns. Many ofthe amendments proposed

are the result ofa high level ofcooperation between the staffand the industry in general. The staffplans to continue to follow manufacturers' progress towards meeting the OBD I1 requirements, and will be ready to address any issues that arise in this process.



### 39.

<)'•APPENDIX A**Listin~** ofProposed Re!!ulatorv Amendments in "Plain Ene:lish"

Section (a)(1.1): In response to questions from manufacturers, a modification is proposed to clarify that use ofthe International Standards Organization (ISO) engine symbol is acceptable in place ofthe word "engine" or "powertrain" for purposes ofthe Malfunction Indicator Light (MIL). The staffbelieves use ofthe symbol will provide for equal effectiveness in alerting vehicle operators ofmalfunction occurrences.

Section (a)(l.2): Forpurposes ofclarity, an additional sentence is proposed to state that. unless otherwise noted, all section references are c'ontained within the OBD II regulation.

Section (a)(1.4): Consistent with the modifications proposed for diesel applications, this section would be deleted.

Section (a)(l.8): The ARB staffhas had· several discussions with manufacturers regarding the use ofalternate statistical MIL illumination criteria. The staffhas determined that more specific approval criteria are necessary to ensure that alternateprotocols will be comparably effectivein indicating malfunctions in timely manner. Specifically, languageis proposed that would require manufacturers to demonstrate the effectiveness ofthealternate protocol relative to criteria specified in theregulation (i.e., illumination ofthe 

### MILifa malfunction is detected in two sequential driving cycles). Further, the staff'sproposal would make clear that the ARB would not accept as comparably timely a protocol that required

more than six driving cycles on average to detect a specific component or system failure mode.

Section (a)(1.9): An amendment is proposed that would modify the protocol for illuminating the malfunction indicator light and storing fault codes when malfunctions are detected. The amendment would remove the unnecessa;-:. restriction that all monitoring strategies must operate before a detected malfunction is :ndicated to the vehicle operator.

Section (a)(2.0): Vehicle operation at very low :;::nperatures or high elevations can potentially cause a temporary effect on the performance ofa system or component. Mahufacturers have indicated that monitoring system dis::blement is necessary under. such conditions to prevent falsely detecting such components 2.5 broken. The staffhas proposed the addition ofthis section to clarify the expected ambient temperature and altitude limits for the operation ofOBD II**mon~toring** strategies. Upon demonstrating the need, manufacturers may request Executive Officer approval to disable monitoring systems ai ambient engine**startin~** conditions below 20 degrees Fahrenheit,·and at 2.ltitudes above

## ·sooo feet above sea ·


# - - ' level. In special circumstances, a manufacturer 

### may**re~·.:est** approval to disable monitoring systems at starting temperatures above 20 degrees.

A-I. '



# ..

Section (a)(2.1): The staffproposes to allowmonitoring system disablement when the vehicle's fuel tank level is low (below 15 percent ofthe nominal capacity) in orderto avoid the false detection ofengine misfire orothermalfunctions should the vehicle run out offuel.

Section (a)(2.2): Manufactu_rers often design medium-duty applicationsto accommodate Power Take-Off(PTO) units. These unitsharness the engine'spowerto drive auxiliary devices such as a dump truck bed, a snowplowblade, oran aerial bucket. The staff proposes to permit OBD 

### II monitoring system disablementwhile such devices are active to avoid the false detection ofmalfunctions. When a PTOunit is activated, the proposed section would require the OBD 

### II system to clearthe system readiness code in orderto avoid vehicle tampering. Section (n)(19.0) contains a proposed definition for PowerTake-OffUnit.

Section (b)(1 ): The staffproposesto modifythe catalystmonitoring requirements for low-emission vehicle applications. Underthe proposal, catalystmonitoring would be based on tailpipe emissions instead offront catalysthydrocarbon conversion efficiency. The regulation would require the OBD 

### II system to indicate a catalyst system malfunctionwhen degraded catalyst system performance causes emissions to exceed 

### 1.5 timesthe hydrocarbon standard for the vehicle. Higher emission malfunction criteriathat wou1d bephased-outbythe2000 model year are proposed to address immediate implementationconcerns.

Section (b)(2.1.2): An amendment isproposedto makethe monitoringrequirements for heated catalysts consistent with the requirements specified in section (b)(1) for conventional catalysts. ·

Section (b)(2.2.1): An amendmentisproposed to delete separate catalystheating monitoring requirements for pre-start and after-startheating strategies. Afterfurther reviewing catalyst heating technologies, the staffbelieves a single criteria (failureto obtain designated temperature within a specific time period afterengine starting such that emissions would exceed 1.5 times the standard) is applicable to both designs, making separate criteria unnecessary. Sections (b)(2.3.2) and (g)(2.7) have also been modified under the staffs proposal to reflect this amendment. ·

Section (b)(3): The staffproposes to provide additional leadtime to manufacturers to meet expanded monitoring conditi.ons for the detection ofenginemisfire. Further, the staffs proposal defines a high engine speed, light engine load vehicle operating region**wh~rein** misfire monitoring may be disabled.

Section (b)(3.1): Manufacturers have expressed co_ncerns that misfire detection systems may not be ca;Pable 

### qfreliably identifying misfiring cylinders when.the misfire occurs at high engine speeds. An amendment is proposed that would allow manufacturers to·request approval to disable cylinder identification strategies under such conditions as long as

# ageneral misfire fault code is stored should misfire be detected.

A-2Section (b)(3.2)(A): Currently, misfire at levelshigh enough to cause catalyst damage
must be detected using 200 revolution intervals. An amendment is proposed to extend this interval to up to 1000 revolutions ifthe manufacturercan demonstrate that catalvstdamaQe 

### v.:ould not occur before

### t~e additional evaluationtirne has elapsed. The

### amend~ent would pro.vide manufacturers with greater flexibility in detecting such misfire problems.

Section (b)(3.2)(B): This section contains a provision for the use ofa misfire detection threshold on low-emissionvehicles that is hi2her than the level ofmisfire that would

. .

# -
cause emissions to exceed 1.5 timesthe standard. Theintent oftheprovision is to provide manufacturers with some relieffrom the misfire detectionrequirements should significant reliability**conc~ms** exist withrespect to these vehicles. The staffproposesto delete this provision. Adequate flexibility regarding for the use ofhigher malfunctionthresholds on lowemission vehicles is provided in section (a)(1.4) making a specific provision with respect to misfire monitoring unnecessary

..

Section (b)(3.4.2): Language is proposed to clarifythe MIL illuminationprotocol 

### • when engine misfire is detected. The amendment would make clearthe section's intent that a malfunctionjsto be indicated ifmisfire is detected on sequential driving cycles regardless of the conditions under which it is detected, or ifmisfire is detected twice sequentiallyunder similaroperating conditions even ifthe occurrence ofthe operatingconditions is separated by

one ormore driving cycles.

Section (b)(3.5): Misfiremonitoringrequirementsareproposed for diesel vehicles and engines. Manufacturers ofdiesel applications would berequired to implementmonitoring systemscapable ofdetecting the lack ofcombustion in one ormore cylinders beginning with the 1998 model year.

Section (b)(4.1.3): The staffproposes a modificationto make clearthat evaporative system leak monitoring may be disabled, subjectto Executive Officer approval, at fuel levels greater than 85 percent ofthe nominal tank capacity. Manufacturers have stated that misdiagnosis ofthe evaporative system can occur at veryhigh fuel levels.

Section (b)(4.2.2): The staffproposesto require manufacturers to phase-in evaporative system monitoring strategies capable ofdetecting system leaks equal or greater in magnitude to a 0.020 inch diameter orifice. Thephase-in would extend from the 1998 model year to the 2000 model year.

Section (b)(5.2.2): An amendment isproposed to clarify the criteriathat will be used by the Executive Officer to determine ifa secondary air system will be sufficiently resistant to deterioration to qualify for a func!ional check. Manufacturers requesting an Executive Officer determination have sometimes misunderstood the extent to which the durability ofthe secondary air system must be demonstrated.

A-3·Section (b)(7.1): An amendmentis proposed to clarifythe fuel system monitoring requirements for diesel vehicles and engines. Manufacturers would not be responsible for detecting fuel system failures for which insufficient information would be available to the diagnostic system.

Section (b)(7.4.2): Language is proposed to clarify the MIL illumination protocol \\'hen a fuel system malfunction is detected. The amendment would make clear the sections intent that a malfunction is to be indicated ifa fuel system ·malfunction is detected on sequential driving cycles regardless·ofthe conditions under which it is detected, orifa malfunction is detected twice sequentially under similaroperating conditions even ifthe

occurrence ofthe operating**c~nditions** is separated by one or more driving cycles. 

# .. •

Section (b)(8.2.2): The staffproposes a modification to clarify the malfunction criteria for oxygen sensorheaters. Some man.ufacturers have presented oxygen sensor heater monitoring strategies thatessentially verify onlypropercircuit continuity ofthe heater, and do not adequately verify its properperformance. Language is also proposed to clarify that data and/oran engineeringevaluation mustbe submitted when a request for Executive Officerapproval is made

..Amendments areproposed to the following sections to similarly clarify the typeofinformation that is required to supporta request for Executive Officer approval: (b)(9.1.2), (b)(lO.l.l)(C), (g)(3.0),

Section (b)(lO.l): An amendmentis proposed to makeclearthat any component used

as part ofthediagnostic strategy for any othermonitored system orcomponent must itselfbe inonitored for properfunction. Somemanufactut:ers have initially neglected to incorporate monitoringstrategies for such components. Manufacturers can beexempted from having to illuminate the MILwhen such a componentis detected as malfunctioning, provided the OBD II system would no longer useinformation provided by the componentas criteria for temporary monitoring system disablement.

Section (b)(lO.l.l)(A): A new exampleis proposed to clarify the requirements for input componentrationality checking.

. Section (b)(lO.l.l)(C): This section requires manufacturers to monitor coolant temperature sensors for performance with respect to indi(:ating the stabilized temperature necessary for closed-loop operation within a specified time period afterengine starting. However, diesel vehicles generally do not employ**cl~sed-loop** fuel control. The staff proposes an amendment for diesel applications that would tie coolant temperature sensor performance with the beginning ofwarmed-up fuel control instead. Additionally, the staff proposes that permitted warm-up times for all vehicles should bea function ofStarting •coolant temperature and/orintake air temperature to ensure that specified maximum warm-up

times reasonably correlate with expected times. 

# In reviewing manufacturers' OBD II system designs, the staffhas found that manufacturers tend to focus on \vorst case operating conditions, making the monitoring strategies ov'erly conservative under normal conditions. By correlating the maximum time with ambient temperaure information. monitoring system

A-4

### effectiveness would be improved.

Section (b)(l0.1.2)(C):. It

### is proposed to add the wait-to-start lamp on diesel applications as an example ofoutput componentsthat may need to be monitored under the Comprehensive Component Monitoringrequirements. The modification clarifies that the lamp is an output component for which monitoring mustbe considered.

Section (b)(I0.2.1): The staffproposesto deleteregulatory text that is redundant with language.in section (b)(IO.l.l)(C).

Section (b)(l0.3): A modification is proposed to clarifythe monitoring conditions for computer input and output components consistent withthe original intent ofthe requirements. The modification would make clearthat input components are to be monitored continuously with respect to out ofrange values, and one<: pertrip at.a minimum for rationality checking. Output components are to be monitored at least oncepertrip for proper function, and continuously with respect to circuit continuity orout ofrange values ifsuch monitoring is

- 

### ' 

# - included.

Section (b)(1

### 0.5): A modification is proposedto make clearthat the determination of

a component's impact onemissionsis not limitedto formal testprocedures such as the FTP cycle orthe Highway Fuel Economy Test,(HWFET). Manufacturers have incorrectly determined that a componentdoes not have to bemonitored ifan emission impactis not**noticeabl~** 

### during an FTPtest, regardless ofthe potential impact on emissions during other driving conditions such as freeway driving orhard.accelerations.

Section (d): The staffproposes an amendmentthat would require enhanced tamper resistance measures for vehicles using Electronically Eraseable Programmable Read Only Memory (EEPROM) devices, which allow for_electronic reprogramming ofvehicle on-board computers. The measures could include the use ofdata scrambling and required access to·offsite computers when installing new programming.

Section (e): Modifications are proposed to clarify the readiness/function code requirements. The proposed language would indicate that the readiness code is to be stored according to the protocol established in SAE 

### 11979 or 

### S:\.E 11939, whichever applies. Some manufacturers have misunderstood howthe readiness/function code is to be implemented. Further, for evaporative system monitoring readiness, the proposed language would make clear that readiness should be indicated when a full diagnostic check with respect to-the 0.040 inch orifice malfunction criteriahas been**~ompleted** 

### ifmore constrained monitoring conditions

are**re~uired** 

### with respect to detecting 0.020_inch leaks. This modification would ensure timely setting ofthe readiness code in-use.

Section (g)(l.O): The requirements for selecting 

### OBD II demonstration vehicles have been clarified to bener reflect the intent ofthe section. Some manufacturers have not 

### • understood that any 

### OBD II equipped engine family can be selected by the 

### ARB for

A-5

### demonstration. The provisions for using an alternate high mileage vehicles instead ofa certification Durability Demonstration Vehicle have also been misunderswod.

Section (g)(2.4): A modification is proposed to exclude diesel applications from the requirements to demonstrate misfire detection capability. Diesel applications have separate misfire detection requirements and the demonstration test specified would not.be applicable.

Sections (g)(2.Q.2), (g)(4.4.5), (h)(9): Modifications are proposed to make the**·~** 

# .

.demonstrationtestprotocol for catalyst monitoring on low-emission vehicles consistent with

the proposedmodifications'to the monitoring requirements.

Section (g)(3.0): Language is proposed to make clear that a cold start is not to be required for demonstration testpreconditioning cycles. Arequired cold start for preconditioning would unnecessarily complicate the demonstration test procedure.

Section (g)(4.0): Amendments to this section are proposed tQ clarify the testing sequence for demonstration evaluationsto better reflect the ARB's intent.

Section (h): A modification is proposed to grantthe Executive Officerthe authority to waive or modify any ofthe requirements for certification documentation ifit is determined that generationofthe information would be redundant or excessively burdensometo the manufacturer. Thisamendmentwould preventmanufacturers from havingto provide winecessary information.

Section (h)(12): The staffproposesto require a description ofdeteriorated components used for all required OBD II demonstration tests in orderto verify that the components are ·appropriate for OBD II demonstration and to aid in OBD II confirmation testing.

Section (h)(l3): The addition ofthis section is proposed to require manufacturers to submit a listing ofall powertrain computer input and output components in the certification application. This information is necessary for the staffto verify that all components subject to the regulation are monitored.

Section (i)(3): An 

### amendment is proposed to make clear that manufacturers will not be held responsible during in-use recall testing for undetected malfunctions caused by tampering or abuse when it is clear that the diagnostic system could not reasonably be expected to detect such failures. ·

Section (i)(5): When it is determined that an OBD II system design is subject to systematic false activation ofthe MIL, the staffproposes to 

### allow manufacturers to request Executive Officer approval to take corrective action otherthan a formal recall ifthe manufacturer demonstrates that alternative action would,

# ce equally effective in capturing and correcting vehicles in the field.

A-6

### Section (i)(6): The catalyst monitoring requirements permit monitoring ofaportion ofthe catalyst system to infer total system performance. The addition ofthis section is proposed to clarify that unmonitored catalysts are to be normally aged during in-use testing in order to limit manufacturers' liability in instances where abnormal deterioration ordamage of_such catalysts has occurred.

Sections (f), 

### (h)(3), (k)(l.O), (k)(2.0), (k)(3.0). (k)(4.0): The staffproposes to update the referenced industry standards to the most recent published versions. The industry has incorporated a number ofmodifications to the referenced documents since they were referenced in 1991. ·

Section (k)(1.0): The staffproposes to limit restrictions on the use ofinter-byte separation and checksums to only the messages specified in SAE J

### 1979 in order to provide additional flexibility in transmitting other emission- and non-emission related messages. The staffdoes not believe that the added flexibility will have 

### i'tllY significant impact on diagnostic tool designs.

Section (k)(5.0): Manufacturersofmedium-duty vehicles and engines h:.we requested approval to use the heavy-duty vehicle communication protocol specified in SAEJ

### 193.9 as an alternative to the referenced SAE and ISO 

### protocols. Medium-duty vehicles are often serviced at establishments specializing in maintaining heavy-duty vehicles, and 'Often require the use ofdifferent diagnostic tools than used for passenger cars and light-duty trucks.· Inclusion ofthe 11939protocol as an option for these vehicles is likely to promotebetter standardization ofheavy/medium-duty diagnostic equipment which could more adequately satisfy the goals ofthe standardization requirements**tha~** 

### would forcing manufacturers to implement a "light-duty" communication protocol solely for emission diagnostics. While the staffbelieves the request is reasonable, the SAEJ

### 1939 document is currently in draft form and has not been thoroughly evaluated by the ARB staff. Therefore, the staffproposes to make use ofthe protocol optional only with Executive Ofticer approval in order to provide the ARB with the opportunity to 

### ensure that**it~** 

### use will satisfy OBD II goals and benetit the vehicle service industry.

Sect1on (1)(2.0): This secllon requ1res manufacturers to publish certain engine operating parameter:, in factory**~ervH.:e** 

### manuah. The p<::-ameters are specific to spark 1gnited engines. Thereiore, a modJficauon 1s proposed :o make clear that the section does not apply to 

### diesels. Further. modifications are proposed to 

### make the information requirements compatible with engines that have a low JT.aximum engine speed and engines that do not use mass air flow sensors.

. 

### . 

### Section (l)n.OJ: The stafiproposes a modification to 

### provide an addition_al year's leadtime to incorporate meam to provide some ofthe**in~·ormation** 

### required.under the-section f'l·1anufacturer'> have requested additional leadtime to**faci~Itate** 

### necessary software moditications. Modnlcations are also proposed to clarir":- the scope ofrequired information. Industry representatives have requested this clarHication.

A-7

### Section (m)(5.1): The staffproposes to providemanufacturers with additional leadtime to address concerns regarding OBD II implementation on alternatefuel vehicles. Theproposal would allow manufacturers, up until the 1999 model year, to request exemption from certain monitoring requirements for these vehicles ifthe use ofalternate fuels could affect the reliability ofthe monitoring strategy. A similarprovision is proposed for California's certification procedures for retrofit alternate fuel vehicles.

Section (m)(5.2): An amendment is proposed to clarify that medium-duty engines certified on an engine dynamometer may comply with the OBD II regulation on an engine model year basis instead ofa vehicle model year basis. consistent with provisions for emissions certification.

Section (m)(6.1), (6.2): Amendments are proposed that would providefor the certification ofOBD II systems with identified monitoring systems shortcomings through the 2000 model year. Forlhe 1996 model**ye~r,** 

### manufacturers would be permitted to certify engine families with up to two monitoring system deficiencies withctut penalty, but would be required to 

### pay fines forthe third deficiency and every additional deficiency. For the 1997

. model year through the 2000 model year, only one deficiency would be permitted per engine family before fines would be imposed. The staffs proposal would not allow the carry over ofdeficiencies after the 1997 model year, except that carry over for one year is permitted if

. hardware chang.es are needed to tix the deficiency. Also. afterthe 1996 model year, tines would be imposed for all monitoring system deficiencies wherein a component or system is left completely unmonitored. ·

Section (n)(l.O): When the determination ofa malfunction is based on vehicle emissions with respect to the applicable standards, both the certification and useful life standards apply (e.g., on a vehicle with less than 50,000 miles, a malfunction is to be indicated with respect to the 50,000 mile standards, whereas at higher mileages, a malfunction would bejudged with respect to the I

### 00.000or 120.000 mile standards). An amendment to 

### this section is proposed to 

### clarify the definition ofa malfunction in this respect.

Section (n)(8.0): A 

### modification is proposed to 

### modify the definition of

..continuous monitoring·· with respect to computer input components that are sampled for engine control purposes at relatively low rates. The amendment makes clear that manufacturers do not need to increase the sampling rate ofacomponent solely for the purposes ofmonitoring.

Section (n)(ll.O): A 

### separate definition for "calculated load value" is proposed for diesel applications. The current definition is not easily c.pplicable to diesels.

·Section (n)( 15.0): 

### The staffproposes to modify the definition for diesel c:ngines to 

### Jncluck only engine::, u::,ing a

### compression ignition thermodynamic cycle. and not spark 1glllted diesel-derived engines. The latter moreclosely :-.:semble conventional spark ignited
, engines than compression ignition engines with respect to 

### the emission control system design.

A-8Section (n)(18.0): For the purposes of the mistire detection requiremems, the staff proposes a definition for ··redline engine speed

.. that is based on manufacturer's InaxiJllum recommended engine speed or the engine speed at which fuel cutoff occurs. Manufacturers have r.equested that the regulation be clarified to reflect 

### this.

A-9'•

### "APPENDIX B

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### APPENDIX C

Modificationsto Sections 1968.1, Title 13, California Code ofRegulations

Note: These are amendments to section 1968.1, Title 13, CCR. The proposed amendments

are shown in underline to indicate additions to the sections and strikeout to indicate deletions.---------------------1968.1 Malfunction and Diagnostic System Requirements--1994 and Subsequent Model-Year Passenger Cars, Light-Duty**Tr~cks,** and Medium-Duty Vehicles and Engines

(a) GENERAL REQUIREMENTS
(1.0) All 1994 and subsequent model-year passengercars, light-dutytrucks, and medium-duty vehicles shall be equipped with a malfunction indicator light (MIL) located on the instrument panel that will automatically inform the vehicle operator in the event ofa malfunction ofany powertrain components which can affect emissions and which provide inputto, or receive output from, the on-board computer(s) orofthe malfunction ofthe on-board computer(s) itself. The MIL shall not be used for any other purpose.



## . . (1.1) The MIL shall be ofsufficient illumination and location to be readily visible underall lighting conditions. The MIL shall illuminate in the en·gine-run'key position before engine cranking to indicate thatthe MIL is functional and shall, when illuminated, displaythe phrase "Check Engine" or "Service Engine Soon". The word

...Powertrain" may be substituted for "Engine" in the previous phrases. Alternatively, the International Standards Organization (ISO) engine symbol may be substituted forthe word "Engine."
(1.2).

(1.3)

(1 4) All 1994 and subsequent model-year passengercars, light-dutytrucks, and medium-duty vehicles required to have MIL pursuant to (1.0) above shall also be equipped with an on-board diagnosticsystem capable ofidentifyingthe likely area of the malfunction by m·eans offault codes stored in computer memory. These vehicles shall be equipped with a standardized electrical connectorto provide access to the stored fault codes. Specific performance requirements are listed below. A glossary of terms is contained in Stltlsection (n), at the end ofthis section._
Any reference to vehicles in this regulation shall also include medium-duty vehicles with engines certified on an engine dynamometer.

Manu7acturerc ofdiesel engine: uti!i7ing**ccmpu::~** based 

### e!::tren:c**p8WefH;..~** systems shall submit a plan for complying vlith tt-.:ce requirements to the Executive Officerfor approval at least two years prior to ce:-:ification The plan shall be approved based on monitoring all powertrain**co~ponents** which can affect emissions and for which reliable monitoring techniques are :vailable at costs comparable to other engines meeting these requirements, and en meeting all other applicable requirements (e.g., storing freeze frame· conditio:--s, m_eeting standardization requirements, etc.).

1 Unless otherwise noted, all section references are contained within this subsection of Title 13, CCR.

C-1**(1.~** For Low Emission Vehicles (LEV), the Executive Officershall revise the emission threshold for a malfunction on any check ifthe most reliable monitoring method developed requires a higherthreshold to prevent significant errors ofcommission in

·detecting a malfunction.
(1

### :e§J For every case in which a malfunction is to be noted when an emission threshold.is exceeded (e.g., emissions in excess of 1.5 times the standard), the manufacturer may perform only afunctional check (defined in section (n)(16.0)) ofa specific component
or system ifdeterioration orfailure ofsuch would not cause tlie vehicle's emissions to exceed**~he** emission threshold.
(1.7§) Afterthe 1998 model year, for Non-LEVs, fulfillment offederal On-Board Diagnostic (OBD) requirements shall be deemed to be an acceptable option forthe manufacturer. forthe purpose ofmeeting these requirements.
(1.&Z) For 1994 and 1995 model years only, illumination ofthe malfunction indicator light upon detection ofa·malfunction shall be optionalfor catalyst, misfire, and complete evaporative system monitoring. MIL illumination forsuch vel'licles shall be optional for other monitoring requirements, subjectto Executive Officer approval, on the basis of
use ofa new monitoring strategy which is sigQificantly differentthan that used previously by the manufacturer and/orwhich entails a high degree ofsophistication in its application. Irrespective ofthe preceding theMIL shall illuminate on thesevehicles in accordance with section 1968.1 for lack offunction (see section (n)(16.0)) for electronic components/systems otherwise approved for not illuminatingthe MIL. Furthermore, setting fault codes·forall malfunctions shall continue to confonn with requirements ofsection 1968.1. For components/systems not requiring illumination of the MIL, manufacturers shall provide·a plan forapproval bythe Executive Officerfor reporting on the correct perfonnance ofthe monitoring systems in customer use at 6 month inter:vals beginning from the start ofproduction each yearforat leastthe first three years after production. Approval ofthe plan shall be based on_obtaining a statistically valid sample size, assuring that adequate resources are available to investigate the potential problems, and assuring that awide variety ofvehicles, operating modes, and mileage accumulation will be included in the evaluation. Should _incorrect performance ofthe diagnosticsystem be detennined by the Executive Officer
on the basis ofthese reports orthrough other means, manufacturers shall recall the vehicles for correction ofthe OBD II system in·accordance with Article 2.2. Title 13 CCR, or they shall submit an alternate plan for remedying the problem for approval by the Executive Officer on the basis ofachieving comparable capture rates and timeliness as an official recall plan.
(1

### .BID Manufacturers may employ alternate statistical MIL illumination and fault code storage protocols to those specified**i~** these requirements, subjectto Executive Officer approval based on comparable timeliness in detecting a malfunction and evaluating system performance. For strategies requirina on average between three and six drivina cycles for MILillumination. the manufacturer shall provide data and/or an engineerina evaluation which adequately demonstrate thatthe monitorina system is equally effective and timely in detectinq'component deterioration. Strateaies requiring
on averaae more than six driving cycles for MIL illumination shall not be accepted.



### C·2f.1.:.m Regarding diagnostic system monitoring conditions and MIL illumination reauirements. manufacturers are generally required to define appropriate operating conditions for monitoring. subject to the limitation that the monitoring conditions shall be encountered at least once during the first engine start portion ofthe applicable Federal Test Procedure (FTP) test. Upon detection ofa malfunction, the MIL is to be illuminated and a fault code stored no laterthan the end ofthe next driving cycle during which monitoring occurs provided the malfunction is again detected. Until the 1997 model year, diagnostic strategies that illuminate the MIL.on the basis of completing atrip (trip is defined in section (n){16.0) ofthese requirements} shall be accepted. When atrip criterion is employed, upon detection ofa malfunction, the diaanostic system shall store afault code and the MIL shall be illuminated no later than the end ofthe nexttrip ifthe malfunction is again present.

(2 0) Manufacturers may request Executive Officer aporoval to disable a diaanostic system desianed to meet the requirements ofsection (b) at ambient engine sta'rting temperatures belowtwenty degrees Fahrenheit. and at elevations above eight thousand feet above sea level provided the manufacturer subr;nits data and/or an engineering evaluation whi.ch adequately demonstrate that monitoring would be unreliable when such conditions exist. Notwithstanding, diagnostic system disablement may be requested at other ambient engine starting temperatures ifthe manufacturer adequately demonstrates with data and/oran engineering evaluation that misdiagnosis would occurdueto the impact ofsuch ambienttemperatures on the performance ofthe component itself (e.g., component freezing).
{£J.l Manufacturers may disable monitoring systems that can be affected by running out of fuel (e.g., misfire detection) when the fuel level is low, provided disablementwill not
occurwhen the fuel level is above 15 percent ofthe nominal capacity ofthe fuel tank.
{£21 Forvehicles designedto accommodate the installation of PowerTake-Off {PTO} units (defined in section (n)(19.0}), disablement ofaffected monitoring systems is permitted provided disablement occurs only while the PTO unit is active, and provided the OBD II readiness code (specified in section (e)) is cleared by the on-board computer upon activation ofthe PTO unit.

(b) MONITORING R=OUiREMENTS

(1 0) CATALYST MONITORING

(1.1) Requirement:
(11.1) LE'is: The diagnostic systern shall**individua~'y** monitorthe front catalyst or catalysts (i.e., any catalyst(s) 'Nhich receive :ngine out unfreated exhaust gas), except that front catalysts may be monitored in combination with the next catalyst dovmstream if it can be demonstrated that a**:-:~alfunction** will be indicated**~~;·hen** tha fron: catal;,'st is alone malfunctioi1ing (so: (b) (1.2.1)).· Catalysts arranged in parallel .,.,.;th the same inlet and outlet in a s;:-:;le exhaust pipe shall be consider:d as one catalyst ,t., separate cata'::-st in?orporated in series into the

C-3same container as afront catalyst shall be considered a downstream catalyst. The diagnostic system shall monitorthe catalyst system for proper performance.
(1.1.2) Ifthe front catalyst is a small volume catalyst (see (b)(1.2.2)), the diagnostic system shall also monitorthe nextcatalyst downstream ofthe small volume catalyst either independently of, or (ifthe conditions in section (1.1.1) are met) in _Qombination with, the small VQiume catalyst.
(1.1.3) Manufacturers may submit other monitoring strategies, subjectto Executive Officer appre'Jal, based on equaltimeliness and reliability in detecting a catalyst malfunction as these requirements.
(1.1.4) Non LEVs: The diagnostic system shall monitorthe catalyst system for proper pertormance.
(1.1.2) Manufacturers are not required to implementthese catalyst monitoring requirements on dieselvehicles and engines.
(1.2) Malfunction Criteria:
(1.2.1) Low Emission Vehicles (see section (n)(14.0)): Each monitored catalyst, or combination ofcatalysts, shall be considered malfunctioning when average Federal Test Procedure (FTP)**tot~l** hydracarnan (HC) con'Jersion efficiency falls between 50 to 60 percent. The efficiency determinatian shall be based an an FTP test'A'herein a malfunction is. noted whenthe cumulative total HC emissions measured atthe outlet afthe monitored catalyst(s) is more than 

### 40to 

### 50 percent ofthe cumulative total engine out emissions measured atthe inlet ofthe catalyst(s). In addition, ifafront catalyst is monitored in combination with a downstream catalyst, the front catalyst shall be considered malfunctianing when its efficiency has deteriorated between 40 to 50 percentfrom its 4000 mile average FTP total HC efficiency. The catalyst system shall be considered malfunctioning when its conversion capabilitydecreases to the pointthat either'of the following occurs: 1) Hydrocarbon (HC) emissions exceed the applicable emission threshold specified in section (b)(1.2.2) below. or2) the average Federal Test Procedure (FTP) Non-Methane Hydrocarbon (NMHC) conversion efficiency ofthe monitored oortion oftho catalyst system falls below 50 oorcent. Reaardino the second criterion. the efficiency determination shall be based on an FTP test wherein a malfunction is noted when the cumulative NMHC emissions measured at the outlet ofthe monitored catalyst(s) are more than 50 percent ofthe cumulative engine-out emissions measured atthe inlet ofthe catalyst(sf
(1.2.2) TLEV applications shall employ an emission threshold malfunction criterion of2.0 times the applicable FTP HC standard plus the emissions from atest run with a representative 4000 mile catalyst system (125 hours ofoperation for medium-duty· vehicles with engines certified on an engine dvnamometer). The emission threshold criterion for LEV applications shall be 2.5 times the applicable FTP HC standard plus the emission level

### wit~ a representative 4000 mile catalyst system. Notwithstanding. beginning with the 1998 model year. manufacturers shall phase



### C·4,·

in an emission threshold of 1.5 times the applicable FTP HC standard for all categories oflow emission vehicles, which shall not include the emission level with a4000 mile catalyst system. The phase in percentages (based on the manufacturer's projected sales volume for low emission-vehicle applications) shall

- equal or exceed40 percent in the 1998 model year/70 percent in the 1999 · model year, with.lOO'percent implementation forthe 2000 model year. ULEV applications shall comply with the 1.5times the standard emission threshold. and shall be included in the phase-in percentages specified above; however. priorto the 1998 model year. the Executive Officershall revise the emission threshold for such vehicles ifthe manufacturer submits data and/or an engineering evaluation · which adequately demonstrate that substantial vehicle body and/orcatalyst system modifications would be necessaryforthis threshold to·be met.
(1.2.2) For LEVs, each small volume catalyst (i.e., :hose designed with a conversion· efficiency too !ov: to be practically monitoicd for 50 to 60 percent average FTP total HC efficiency) monitored independently shall be considered**mal~unctioning** when its average FTP conversion efficiency has deteriorated by between '10 to 50 percent from its '1000 mile conversion efficiency.
(1.2:3) Non-Low Emission Vehicles: The catalyst system shall be considered malfunctioning when its conversion capability decreases to the point that HC emissions increase by more than 1.5 times the standard overan FTP test from a test run with a representative 4000 mile catalyst system.
(1.2.4) For 1994 and 1995 model yearvehicles and engines LEVs and Non LEVs, as an option to monitoring the catalyst during FTP driving conditions, manufacturers may monitorthe front catalyst independentlyof,

# or in combination with, the next catalyst <;lownstream. Each monitored catalyst orcatalyst combination shall be considered malfunctioning when total HC conversion**~fficiency**falls below 60 percent while in normal closed loop operation. As a guideline, the catalyst(s) should not be considered malfunctioning when its efficiency is greaterthan 80 percent. The efficiency determination shall be based on a steady state test wherein a malfunction is noted when the total HC emission concentration measured at the outlet ofthe monitored catalyst(s) is more than 20 to 40 percent ofthe cumulative total engine-out emissions measured at the inlet ofthe cata!yst(s). Alternatively, ifco;re!ation with FTP emissions can be demonstrated manufacturers may use the malfunction crite:ia specified in (b)(1.2.1) or (b)(1.2.3). 1994 and 1995 model year vehicles certified to this option shall incorporate FTP based monitoring no laterthan the 1997 model year (vehicles initially complying with section 1968.1 in the 1996 model year shall utilize an FTP based catalyst monitoring system).
(1.3) Monitoring Conditions:

.(1.3.1) /l, catalyst monitoring check shall occur at la:st once per·trip except for vehicles utilizing steady state monitoring, which shall :omplyV·o'ith section (1.3.2). "Trip" IS defined in section (n) (5.0). This trip definiti21 applies throughout section 1968 1. The manufacturer shall define aporooriate oceratino conditions during which



### C·5·,

# .

monitoring shall occur, subject to the limitation thatthe monitoring conditions shall be encountered at least once during the first engine start portion ofthe applicaole FTP test. However. vehicles utilizing steadystate monitoring (as permitted by section (1.2.3) above). may alternatively comply with the monitoring conditions specified in section (1.3.2). The monitorina system shall operate at least once perdriving cycle during which the manufacturer-defined monitoring conditions are met.
(1.3.2) Ifsteady state efficiency is being monitored (see section (b) (1.2.4)), the manufacturer shall choose a non-closed throttle, reasonably steady speed condition for monitoring the catalystwith the constraints thatthe check shall (i)
occurbetween 20 mph and 50 mph, orwithin an engine rpm and torque range determined bythe manufacturerto be representative ofmedium-duty vehicle operating conditions between 20 and 50 mph steady speed conditions with a load equivalentto 50 percent ofthe maximu,m load carrying capacity, (ii) take no more than a20 second intervalto determine boththat the vehicle is operating in a properwindowto perform the check and to actually perfprm the check, and (iii) be conducted at the earliest such condition encountered afterthe beginning of closed-loop operation for each driving cycle. Performance ofthe check may be ·delayed afterengine startup until stabilized coolant.temperature is achieved and/or asuitable cumulative time interval ofnon-closed throttle vehicle operation has elapsed to ensure the catalyst is warmed-up for properly performing the monitoring check. The specified cumulative time interval shall begin from the first non-closed throttle operation eitherafter achieving a stabilized coolant temperature orafterengine starting and shall not exceed 180seconds. These monitoring constraints and conditions may

### be altered, subjectto Executive Officer Approval. Such approval shall be granted ifthe·manufacturer submits data and
an engineering evaluationjustifyingthe needforthe exception and demonstrates thatthe requested alteration would yield improved catalyst monitoring. "Reasonably steady" speed interval in this instance means a 20 second period where all accelerations and decelerations are ofan average magnitude equivalent to 0.5 mph/second or less over anytwo second interval during this period. The manufacturer may abort the check ifthe engine operating conditions change during the check so thatthe vehicle exceedsthe speed or acceleration/deceleration tolerances before the end ofthe checking interval. The manufacturei may base perfoimance ofthe catalyst check upon engine RPM and load conditions equivalent to the above monitoring conditions. If a manufacturer develops a means ofmonitoring catalyst efficiency which cannot utilize a steady state monitoring period (e.g., examining time vs. temperature during catalyst warmup), it_may present a monitoring proposal to the Executive Officerfor approval based on equivalent accuracy and timeliness as the steady state monitoring protocol in detecting a malfunctioning catalyst.
(1.4) MIL Illumination and Fault Code Storage:
(1.4.1) Except as noted below, upon detecrion o7 a ;atalyst malfunction, the diagnostic system shall store afault code and the MIL ::.all be illuminated no laterthan the end ofthe nexttrip ifthe malfunction is 

### aga::- present. upon detection ofa

C-6catalyst malfunction: the MIL shall illuminate and afault code ·stored no laterthan the end ofthe next driving cycle during which monitoring occurs provided the malfunction is again present. · (1.4.2) For steady state catalyst efficiency checks, upon detection ofcatalyst efficiency below60 percent, the diagnostic system may perform up to two successive monitoring checks priorto informing the vehicle operator ofa malfunction. These monitoring checks need not occur on the same driving cycle, but shall be performed as soon as proper monitoring conditions**o~cur.** Ifcatalyst efficiency remains below

## so·percent forthe three sequential checks, afault code shall be stored and the MIL shall then be activated.
(1.4.3) The diagnostic system shall temporarily disable catalyst monitoring when a malfunction exists which could affect the proper evaluation ofcatalyst efficiency.
(1.4.4) The monitoring method forthe catalyst(s) shall be capable ofdetecting when a catalysttrouble code has been cleared (except diagnostic system self-clearing), but the catalyst has not been replaced (e.g., catalyst**ove~emperature** approaches may not be acceptable).·
(2.0) HEATED CATALYST MONITORING
(2.1) Requirement:
(2.1.1) The diagnostic system shall monitor all heated catalyst systems for proper heating. · (2.1.2) In addition to the non heated catalyst require_ments in section (b) (1), the HC conversion efficiency ofall heated catalysts shall each be monitored. Manufacturers may monitor heated catalysts in combination with another catalyst ifit can be demonstrated that a malfunction 'Nill be indicated 'Nhen the heated cataiyst is malfunctioning. Otherwise, the heated catalyst shall be monitored independently. Ifa heated catalyst is a small volume front catalyst, the diagnostic system shall also monitorthe next catalyst downstream either independently of,
or (ifthe conditions above are met) in combination with, the small volume heated**ca_ta!ys~.** The efficiency of heated cataivsts shail be monitored in conjunction with the reauirements ofsection (b)(1).
(i2) Malfunction Criteria:
(2.2.1)

(2.2.2-jjPre Start Heated Catalyst Systems: The system shall be considered malfunctioning when the designated pre start catalysttemperature is not attained before :ngine starting.**/\~or** Start Heated Catalyst Systems The catalyst heating system shall be considered malfunctioning when the catalyst does not reach its designated heating temperature within a**requi~ite** time period after engine starting. The time ;Jeriod is to be determined by the manufacturer subject to the requirement

C-7that the system shall detect a heating system malfunction causi[lg emissions from avehicle equipped with the heated catalyst sys_tem to exceed 1.5times any ofthe applicable FTP standards.**(2.2.~~** . Manufacturers uslng other heating or monitoring strategies may submit an alternate plan for approval by the.Executive Officerto monitor heated catalyst systems based on comparable reliability and timeliness tothese requirements in detecting a catalyst heating malfunction.
(2.2.4) Except as noted in section (b) (1.2.4), the diagnostic system shall use the malfunction criteria specified in section (b)(1.2.1) or section (b) (1.2.2), 'tYhichever is applicable, when monitoring the conversion efficiency efa heated catalyst.
(2.3) Monitoring Conditions:
{2.3.1) Manufacturers shall define appropriate operating conditionsfor monitoring ofthe catalyst heating system. subjecttothe limitation thatthe monitoring conditions shall be encountered at least once durina the first engine start portion ofthe

- aoolicable FTP test. The monitoring system shall operate at leastonce per driving cycle during which the manufacturer-defined monitoring conditions are met. _Pre 5tart Heated Catalyst Systems: The diagnostic system shall monitor t_he heating system for proper operation once pertrip. Manufacturers may disable the monitoring system for one engine start ifduring the previous driving cycle the vehicle traveled lessthan the equi,,•alent ofthe first one mile ofFTP driving.
(2.3.2) After5tart Heated Catalyst Systems: The diagnostic system shall monitorthe heating system for proper operation once pertrip. Manufacturers may disablethe monitoring system for one engine start ifduring the**previo~:~s** driving cycle the vehicle traveled lees than the equivalent ofthe first one mile of FTP driving.
(2.3.3) Except as noted in section (b) (1.2.4), the diagnostic system shall monitorthe ccnv:rcion efficienc)' ofall heated catalysts at least once pertrip.
(24) M!L Illumination and Fault Code Storage:**~2** -1 1; Upon detection.ofa catalyst heating malfunction, the diagnostic system shall stcr: afault code and the MIL ehal! be illuminated no laterthan the end ofthe**next_~:ip** ifthe malfunction is again present the MIL shall illuminate and afault code stored no laterthan the end ofthe next driving cycle during which monitoring occurs provided the malfunction is again present.
(2.4.2) Fer r.eatf::dcatalyst efficiency malfunctions, the MIL shall be illuminated, and a fault :ode stored according to section (b) (1.4).
(3 0) MISFIRE MONITORING
(3 1) Requirement: The diagnostic system shc!fl monitor engine misfire and shall identifythe specific cyiinder experiencing misfire. Manufacturers may request Executive Officer

C-8approval to store a general misfire·fault code instead ofa cylinder specific code under certain operating conditions provided the manufacturer submits data and/or an engineering_evaluation which adequately demonstrate thatthe misfiring cylinder cannot be reliably identified when such conditions occur. Ifmore than one cylinder is misfiring, aseparate_ code shall indicate that multiple cylinders are misfiring (specifying the individual misfiring cylinders underthis condition is optional, however, identifying only one misfiring cylinder shall not occurwhen a multiple misfire code is stored).
(3.2) Malfunction Criteria: The manufacturer shall specify in the documentation provided for certification (see subsection (g) and (h) infra.) a percentage ofmisfires out ofthe total number offiring events necessaryfordetermining a malfunction for each ofthe conditions listed below.
(A) The percent misfire evaluated in 200 revolution increments for each engine speed and load condition which would result in catalyst damage. Subject to Executive Officer approval. a longer interval (up to 1000 revolutions) may be employed provided the manufacturer submits data and/oran engineering evaluation which adequatelv demonstrate that catalyst damage would not occurdue to unacceptably high catalyst temperatures before the interval has elapsed. The

. manufacturer shall submit in the certification documentation catalyst temperature data versus percent misfire overthe full range ofengine speed and load conditions. The data shall be obtained from a representative cross section ofa manufacturer's engine offerings from small to large displacements. Up to**t~ree** such engine evaluations shall be documented per manufacturer, though a ' manufacturer may submit more data ifdesired. An engineering evaluation shall be provided for establishing malfunction criteria forthe remainder ofengine families in the manufacturer's product line. The Executive Officershall waive the evaluation requirement each year if, in thejudgment ofthe Executive Officer, technological changes do not affect the previously determined malfunction criteria;
(B) The percent misfire·evaluated in 1000 revolution increments which would cause emissions from adurability demonstration vehicle to exceed 1.5 times any ofthe applicable FTP standards ifthe degree of misfire were presentfrom the beginning ofthe test. Ifthe level of misfire determined underthis requirement is significantly lov.'erfer an LEV as opposed to a Non LEV wi!h a similar engine design

.. the iiianuf:cturer may request approvol from the Executive Officerto use a higher parcer.:aga of misfire as the malfunction criteria forthe LEV, not to exceed the level e7the Non LEV. For the purpose ofestablishing the percent misfire, the manufacturer shall conduct the demonstration test(s) with the rnisfire events occurring at equally spaced complete engine cycle intervals, across randomly selected cylineers throughout each 1000 revolution increment. However, the percent misfire established shall be applicable for any misfire condition (e.g. random, continuous. equally spaced, etc.) forthe purpose ofidentifying a malfunction. This criterion shall be usedfor all vehicles with engines containing the same number of cylinders as the demonstration vehicle. The number of. misfires in 1000 revolution incremer¥s which was determined for the durability demonstration vehicle malfunction criterion may be used to establish the

C-9corresponding percent misfire malfunction criteria for engines with other numbers ofcylinders. The**m~lfunction** criteria for a manufacturer's product line shall be updated when a newdurability demonstration vehicle is tested which indicates
more stringent criteria are necessarythan previously established to remain within the above emission limit;
(C) The degree ofmisfire evaluated in 1000 revolution increments which would cause a durability demonstration vehicle to fail an Inspection and Maintenance program tailpipe emission test. This criterion shall applyto vehicles with the same number ofcylinders as the demonstration vehicle. The numberofmisfires in 1000 revolution increments which was determined forthe durability demonstration vehicle malfunction criterion may be used to establish the corresponding percent misfire malfunction criteria forengineswith othernumbers ofcylinders. The malfunction criteria for a manufacturer's product line shall be updated when a newdurability demonstration vehicle·istested which indicates more stringent criteria are**nec~ssary** than previously establishedto ensure passing an Inspection and Maintenance test, orwhen the Inspectionand Maintenance test is revised.
(3.3) Monitoring Conditions: For 1997 and later model yearvehicles, misfire shall be monitored continuously and underallpositP.te torque engine speeds and conditions.
(3.3.1) Forpre 1997 model yearvehicle.s, Pre-1997 Model YearVehicles: 'misfire shall be monitored continuously during, at a minimum, positive torque operating conditionswithin the range ofengine speed and load condition combinations encountered during an FTP test; nonetheless, subjectto Executive Officer approval, manufacturers may employ higher misfire percentage malfunction criteria disable misfire monitoring underspecific conditionswithin the range of operating conditions encountered during an FTP test ifthe manufacturer provides data and/oran engineering evaluation which Ga-Radequately demonstrate thatthe detection'oflower levels ofmisfire· monitoring is notwould not be reliable feasible forthe vehicle model in questiohwhen such.conditions are encountered without making.fundamental engine or control unit design modifications. Ifthe manufacturer can so demonstrate that even the detection ofa higher misfire percentaaes is not feasible undersoecific FTP operatina conditions. the manufacturer may request Executive Officer approval to disable the monitoring system when such conditions are encountered. Further, with Executive Officer approval, the manufacturer may disable misfire monitoring when misfire cannot be distinguished from other effects v.,rhen using the best available monitoring technology. The manufacturer shall present data and an engineering evaluation to the Executive Officertojustifythe proposed action.
(3 3.2) 1997and Later Model YearVehicles: Manufacturers shall phase in expanded misfire monitorina conditions beainnina with the 1997 model vear. The phase in percentages (based on the manufacturer's projected sales volume for a·ll vehicles and enaines) shall equal or exceed.SO oercent in the 1997 model year. 75 percent in the 1998 model year. 90 oercent in the 1999 model year. with 100 percent implementation for the 2000 model year. Small volume manufacturers

C·10shall not be required 

### to meet the phase-in percentaaes: however. 100 percent implementation ofthese monitoringconditions shall be required beginning with the 2000 model year. On vehicles meeting these phase-in percentaaes, except
as provided for in section (3.3.3) below, monitoring for misfire shall be continuous and underall positive torque engine speeds and load conditions. Vehicles not meeting the monitoring conditions ofthis section shall meet the monitoring conditions specified in section (b)(3.3.1) above.
(3.3.3) As an exception to monitoring misfire during all positive torque operating conditions, manufacturers may disable misfire monitoring in the engine operating region bound bythe positive torque line (i.e., engine load with the transmission in neutral). and the two following engine operating points: an enaine speed of3000 rpm with the engine load at the positive torque line, and the redline engine speed (defined in section (n)(18.0)) with the enaine's manifold vacuum at four inches of mercury lowerthan that at the positive·toraue line. Below is a diaaram ofthe permitted misfire detection disablement reaion with respect to the reauirements of this section. Further, with Executive 0fficeraoproval, the manufacturer may disable misfire monitoring when misfire cannot be distinguishedfrom other effects (e.g., rough roads, transmission shifts. etc.) when using the best available monitorina technology. The manufacturer shall present data and/or an enaineerina evaluation to the Executive Officerto justify the proposed action. Executive Officer approval shall be based on the extent to which monitoring is exoectedto be disabled in relation to the capabilities ofthe best available monitoring technologies as applied to otherenaines. ·

'0 ·1'0 0 _; Q) c Vl c w

idle 2000Postive Torque Load

- 4 inches Hg

## ~I

3000 4000 5000 Redline

Engine Speed



## c.1 1(3.4) MIL Illumination and Fault Code Storage:
(3.4.1) Except as provided below, upon detection ofthe level ofmisfire specified in subsection (3.2) (A), theMIL shall blink once persecond during actual misfire conditions and remain continuously illuminated otherwise. In vehicles which provide fuel shutoffand defaultfuel control to prevent overfueling during misfire conditions, the MIL need not blink and may instead illuminate continuously upon detection ofmisfire provided thatthe fuel shutoffand defaultcontrol shall be activated as soon as misfire is detected. Fuel shutoffand defaultfuel control may be deactivated onlyto permit fueling outside ofthe misfire range.
(3.4.2) Upon detection ofthe misfire levels specified in subsection (3.2) (B) or (C), the MIL shall be illuminated and afault code stored no laterthan the end ofthe next driving cycle ifmisfire is aaain detected. Ifmisfire is not detected during the second driving cycle, the MIL shall be illuminated and a fault code stored no later than the next driving cycle in which misfire is detected, unless driving conditions similarto those underwhich misfire was originally**detect~d** have been encountered (see section (3.4.3)) without an indication ofmisfire, in which case the initial temporary code and stored conditions may be erased. Furthermore, if similardriving conditions are not encountered during 80 driving cycles**~** subsequentto the initial detection ofa malfunction, the initial temporary code and stored conditions may be erased.
(3.4.3) Upondetection ofmisfire, manufacturers shall store the engine speed, load, and warm-up status (i.e., cold orwarmed-up) underwhich the first misfire eventwas detected. A trip ordriving cycle shall be considered to have similar conditions if the stored engine speed conditions are encountered within 375 rpm, load conditions within 10 percent, and the same warm-up status is present. With Executive Officer approval, other strategies for determining ifsimilar conditions have been encountered may be employed. Approval shall be based on comparable timeliness and reliability in detecting similar conditions.
(3.5) MISFIRE MONITORING FOR DIESELS
(3.5.1) Requirement: Beainninq with the 1998 model year. the diaanostic system on a diesel engine shall be caoabie ofdetectina the lack of combustion in one or more cylinders. The diaanostic system shall also identify the specific cylinderforwhich combustion cannot be detected. Ifthe lack ofcombustion is present in more than
one cylinder, a separate code shall indicate that multiple cylinders are

. malfunctioning (specifying the individual malfunctioning cylinders underthis condition is optional; however, identifying one malfunctioning cvlindershall not
occurwhen a multiole cylinder code is stored).

' (3.5.2) Malfunction Criteria: A cylinder shall be considered malfunctioning when combustion cannot be detected.



### • (3.5.3) Monitoring Conditions: Manufacturers shall define aopropriate operating conditions for monitoring subject to the limitation that the monitoring conditions

C·12shall be encountered at least once during the·first engine start portion ofthe applicable FTP test. The monitoring system shall operate at least once per driving cycle during which the manufacturer-defined monitorina conditior:Js are met.



## . . ·(3.5.4) MIL Illumination and Fault Code Storage: The MIL shall illuminate and a fault code shall be stored no**late~** than the end ofthe next driving cycle during which monitoring occurs provided the malfunction is aaain present.
(4.0) EVAPORATIVE SYSTEM MONITORING
(4.1) Requirement:
(4.1.1) The diagnostic system shall verify airflow from the complete evaporative system. In addition, the diagnostic system shall also monitorthe evaporative system for the loss ofHC vapor into the'atmosphere by performing a pressure orvacuum check ofthe complete evaporative system.
(4.1.2) Manufacturers may temporarily disable the evaporative purge system to perform
a·check.
(4.1.3) Manufacturers may request Executive Officerapproval to disable orabort an evaporative system check underspecific conditions (e.g., when the fuel tank level is over85 percent ofnominal tank capacity) if

### it can be data and/oran engineering evaluation are provided which adequately demonstratee.that a

.reliable check cannot be made when these conditions exist.
(4.1.4) Subjectto Executive Officerapproval, other monitoring strategies may be used provided the manufacturer provides a description ofthe strategy and supporting data showing equivalent monitoring reliability and timeliness in detecting an evaporative system malfunction or leak.
(4.1.5) Implementation ofthis requirement is mandatory only for 1996 and later model yearvehicles designed to comply with the requirements ofTitle 13, California Code of Regulations, Section 1976, "Standards and Test Procedures for Motor Vehicle Fuel Evaporative Emissions," for' 1995 and subsequent model year vehicles.
(4.2) Malfunction Criteria:
(4.2.1) An evaporative system shall be considered malfunctioning when no airflowfrom the system can be detected, orwhen a system leak is detected that is greater than orequal in magnitude to a leak caused by a 0.040 inch diameter orifice in any portion ofthe evaporative system excluding the tubing and connections between the purge valve and th·e intake manifold. · · (4.2.2) Beginning with the 1998 model year. manufacturers shall phase-in diaanostic strateaies to detect system leaks areater thar. or eaual in maanitude to a leak

C-13caused by a 0.020 inch diameter orifice. The phase-in percentages (based on the manufacturer's projected sales volume for all vehicles) shall equal orexceed 50 percent forthe11998 model year, 75 percent for the 1999 model year. and 100 percent implementation forthe 2000 model year.· Small-Volume manufacturers ·shall not be subject to the phase-in requirements; however. 100 percent implementation shall be required for 2000 model year.
(4.2.3) On vehicles with fuel tank capacity greaterthan 25 gallons, the Executive Officer

. shall revise the size ofthe orifice ifthe most reliable monitoring method available

cannot reliably detect a system leak oftffi&the magnitudes indicated.above.

- (4.3) Monitoring Conditions; The monitoring system shall monitorthe evaporative system at least once pertrip. Manufacturers shall define aporopriate operating conditions for monitoring. subject to the limitation thatthe monitoring conditions shall be encountered at least once during the first engine start portion.ofthe applicable FTP test. The monitoring system shall operate at leastonce perdriving cycle during which the manufacturer-defined monitoring conditions are met. However,, monitoring conditions may be further limited with respect to detecting leaks equivalentto e 0.020 inch diameterorifice, subjeet to Executive Officer approval, on the basisthatthe monitoring conditionswill be reasonably-occurring in-use, and provided that a checkfor leaks equal orgreater in magnitude than a 0.040 inch orifice will continue to be conducted at least once perdriving cycle as indicated above. Subjectto Executive Officerapproval, ifperformance ofthe check causes vehicles to exceed applicable emission standards when**u~ing** the best available technology,·manufacturers may perform evaporative system monitoring during a steady-speed condition, as defined in section (b) (1.3.2), between 20 and 50 mph.
(4.4) MIL Illumination and Fault Code Storage:
(4.4.1) Upon detection ofan evaporative system malfunction ora malfunction that prevents completion ofan evaporative system check, the MIL shall illuminate and
afault code shall be stored no laterthan the end ofthe next driving cycle during which monitoring occurs provided the malfunction is again present. the diagnostic system shall store afault code and the MIL shall illuminate no laterthan the·end ofthe noxt trip ifthe malfunction is again detected.
(4.4.2) Ifthe diagnostic system is capable of discerning that a system leak is being caused by a missing or improperly secured fuel cap, the manufacturer may notify the vehicle operatorthrough the use ofan indicator light otherthan the MIL. The manufacturer is not required to store afault code in this case. The indicator light shall conform to the requirements .outlined in section (a) (1.1) for location and illumination. As another option, the manufacturer may extinguish the MIL, provided no other malfunctions have been detected, and may erase the fault code corresponding to the problem once the on-board diagnosticsystem hasverified that the fuel cap specifically has been securely fastened. Other equivalent strategies shall be considered by**th~** Executive Officer

..

C-14(5.0) SECONDARYAIR SYSTEM MONITORING
(5.1) Requirement: Any vehicle equipped with any form ofsecondary air delivery system shall have the diagnostic system monitorthe properfunctioning of (i) the secondary air delivery system and (ii) any air switching valve.
(5.2) Malfunction Criteria:
(5.2.1) The diagnostic system .shall indicate secondary air delivery system malfunction when the flow rate falls belowthe manufacturer's specified lowflow limit such that
·avehicle would exceed 1.5·times any ofthe applicable FTP emissi.on standards. · (5.2.2) Manufacturers adeauately demonstrating that deterioration ofthe flow distribution system is unlikely may request Executive Officerapproval to perform only a functional check ofthe system. .A.s part ofthis demonstration, manufacturers shall demonstrate that the materials used forthe secondary air system (e.g

.. air hoses, and tubing) are inherently resistant to corrosion orotherdeterioration. 

# m such a case, Ifa**functiona~**check is approved, the diagnostic system shall indicate a malfunction when some degree ofsecondary airflow is not detectable in the exhaust system during a check.
(5.3) Monitoring Conditions: The monitoring ofthe secondaPf air delivery system and the air switching valve shall occur once pertrip. Manufacturers shall define appropriate operating conditions for monitoring ofthe secondary airsystem, subjectto the limitation thatthe· monitoring conditions shall be encountered at least once during the first engine start portion ofthe applicable FTP test. The monitoring system shall operate at least
once perdriving cycle during which the manufacturer-defined monitoring conditions are met. · (5.4) MIL Illumination and Fault Code Storage: The diagnostic system shall store afault code and the MIL shall illuminate no laterthan the end ofthe nexttrip ifthe malfunction is again detected next driving cycle during which monitoring occurs provided the malfunction is again present.
(6.0) AIR CONDITIONING SYSTEM REFRIGERANT MONITORING
(6.1) Requirement:
(61.1) The diagnostic system shall monitor air conditioning systems for loss of refrigerants which could harm the stratospheric ozone layer or are reactive in forming atmospheric ozone. Any sensor used for such monitoring shall itself be monitored for properCircuit continuity and proper range ofoperation. A provision for ensuring that a leak has been corrected before extinguishing the MIL shall be provided.
(6.1.2) Manufacturers ofa model vehicle which will phase out the use of chlorofluorocarbons in its air conditioning systems by the 1996 model-year or which will use federally-approved refrigerants with substantially less atmospheric



## c.15ozone depleting potential than CFC-12 need not comply with this requirement for that model.
(6.?) MalfunctionCriteria: Manufacturers shall provide a monitoring strategy for approval by the Executive Officerfor monitoring a refrigerant leak. The approval shall be based on timeliness and reliability in detecting a leak.
(6.3) Monitoring Condibons: The diagnostic**sy~tem** shall monitorthe air conditioning system at least once pertrip. Manufacturers shall define appropriate operating conditions for monitoring, subjectto the limitation thatthe monitoring conditions shall be encountered at least once during the first engine start portion·ofthe applicable FTP test. The monitoring system shall operate at least once perdriving cycle during which the manufacturer-defined monitoring conditions are met
(6.4) MIL Illumination and Fault Code Storage: The diagnostic system shall store a fault code and the MIL shall illuminate no laterthan the end ofthe nexttrip ifthe malfunction is again present driving cycle during which monitoring occurs provided the malfunction is again present. The diagnostic system shall not clearafault code and the MIL shall not turn offunless the leak has been corrected.
(7.0) FUEL SYSTEM MONITORING
(7.1) Requirement: The di_agnostic system shal! monitorthe fuel delivery system for its abilityto provide compliance with emission standards. ·Fordieselvehicles and enaines. the manufacturer shall monitorthe performance ofall electronicfuel system components to the extent feasible with respect to the malfunction criteria specified·in section (7.2) below.

I (7.2) Malfunction Criteria: The manufacturer shall establish malfunction criteria to monitor the fuel delivery system such that avehicle's emissions would not exceed 1.5times any ofthe applicable FTP standards before

# afault is detected. Ifthe vehicle is equipped with fuel trim circuitry, the manufacturer shall include as one ofthe malfunction criteria the condition where the trim circuitry has used up all ofthe trim adjustment allowed within the manufacturer's selected fimit(s). Manufacturers may :::o;-:,pensate the criteria limit(s) appropriately for changes in altitude orfor temporary**int~~duction** of large amounts of purge vapor orfor other similar identifiable operating**co~ditions** when they occur. (7.3) Monitoring Conditions: The fuel system shall be monitored continuously forthe presence ofa malfunction.·
(7.4) MIL Illumination and Fault Code Storage:

Forfuel systems with short-term trim only capability, the diagnostic system shall store afault code afterthe fuel system.has attained the criteria limitfbr a manufacturer-defined time interval sufficient to determine a malfunction. Ifthe malfunction criteria limit and time interval are exceeded, the MIL shall be illuminated and a fault code stored no laterthan the end ofthe next driving cycle

C-16in which the criteria and interval are again exceeded, unless driving conditions similarto those underwhich the problem was originally detected have been encountered (see section (7.4.3)) without such an exceedance, in which case the initial temporary code and stored conditions may be erased. Furthermore, if similar driving conditions are not encountered during 80 driving**cycles~** subsequentto the initialdetection ofa malfunction, the initial temporary code and stored conditions may be erased.
(7.4.2) For_fuel systems with long-term fuel trim capability, upon attaining a long-term based malfunction criteria limit independent of, or in combination with, the short-term trim system status, the MIL shall be illuminated and afault code stored
no laterthan the end ofthe next

### t$driving cycle ifthe malfunction is again detected. Ifthe malfunction is not detected during the second driving cycle. the MIL shall be illuminated and afault code stored no laterthan the next driving cycle in which the malfunction is again detected, unless driving conditiOJlS similar to those underwhich the problem was originally detected have been encountered (see Stlbsection (7.4.3)) without an indication ofa malfunction, in which case the initial temporary code and stored conditions may be erased. Furthermore, if similar driving conditions are not encountered during 80 driving cycles**~** subsequentto the initial detection ofa malfunction, the initial temporary code and stored conditions may be erased.
(7.4.3) Upon detection ofafuel system malfunction, manufacturers shall store the engine speed, load and warm-up status (i.e., cold orwarmed-up) underwhich the malfunction was detected. A trip ordriving cycle shall be considered to have similar conditions ifthe stored engine speed is encountered within 375 rpm, load conditions within 10 percent, and the same warm-up status is present. With Executive Officerapproval, otherstrategies for determining ifsimilar conditions have been encountered may be employed. Approval shall be based on comparable timeliness and reliability in detecting similar conditions.
(8.0) OXYGEN SENSOR MONITORING
(8.1) Requirement:
(81.1) The diagnostic system shall monitorthe output voltage, response rate, and any other parameter which can affect emissions, ofall primary (fuel control) oxygen (lambda) sensors for malfunction. It shall also monitorall secondary oxygen sensors (fuel trim control or use as a monitoring device) for proper output voltage and/or response rate. Response rate is the time required for the oxygen sensor to switch from lean-to-rich once it is exposed to a rict:ler than stoichiometric exhaust gas orvice versa (measuring oxygen sensor switching frequency may not be an adequate indicator ofoxygen sensor response rate, particularly at low speeds).**(~.1.2)** Eitherthe lean-to-rich or both the lean-to-rich and rich- to-lean response rates shall be checked. Response rate ct1ecks shall evaluate the portions ofthe sensor's dynamic signal that are most affected by sensor malfunctions such as

C-17aging orpoisoning.

Manufacturers may observe the voltage envelope ofthe sensorwhen cycled at a frequency of 1.5 Hertz orgreater, as determined by th.e manufacturer, to evaluate
a slow response rate sensor (i.e. a slow sensor cannot achieve maximum and/or minimum voltage as will a good sensor given a properly chosen switching**freq~~ncy** and fuel step changefqrthe .check). ·With Executive Officer approval, manufacturers may use othervoltage requirements/fuel-air switching frequencies
or monitoring strategies based on a determination ofaccurate and timely evaluation ofthe sensor.
(8.1.3) For sensors with different characteristics, the manufacturer shall submit data and
an engineering evaluation to the Executive Officerforapproval based on showing equivalent evaluation ofthe sensor.
(8.1.4) Forvehicles equipped with heatedoxygen sensors, the heatercircuit shall be monitored for proper current and voltage drop (note: a continuity check ofoxygen sensors is not required). Otherheatercircuit monitoring strategies would require approval by the Executive Officer**bas~d** on equally reliable and timely indication ofmalfunction as current orvoltage-based monitoring.
(8.2) Malfunction Criteria:
(8.2.1) An oxygen sensorshall be considered malfunctioningwhenthe voltage, response rate, orothercriteria are exceeded and causes emissions from avehicle equipped with the sensor(s) to exceed 1.5times any ofthe applicable FTP standards, orwhen the criteria ofsensors foruse as a diagnosticsystem monitoring device (e.g., forcatalystefficiency monitoring) are exceeded.
(8.2.2) For heated oxygen sensors, the heatercircuit shall be considered malfunctioning when the current orvoltage drop in the circuit is no longerwithin the manufacturer's specified limits for proper normal operation (i.e

.. within the criteria reauired to be met by the compor:1ent vendorfor heatercircuit performance at high mileage). Subject to Executive Officerapproval, other monitoring strategy malfunction criteria for detection ofheatercircuit·malfunctions may be used provided the manufacturer submits data and/oran enaineerina evaluation adequately showing monitoring reliability andtimeliness to be equivalentto the stated criteria in this paragraph.
(8.3) Monitoring Conditions:
(8.3.1) For primary oxygen sensor(s) used forfL,Jel control, the response rate and output voltage shall be monitored for malfunction before the end ofthe first idle period after

### tire vehicle has commenced closed-loop operation, ifthe necessary checking condition for acceptable oxygen sensor(s) performance 'has been encountered. The performance ofthe sensorcan'Only bejudged acceptable by one or more of the following means: within any 20 second reasonably steady speed conditionas defined in (b) (1.3.2), within any deceleration of3 seconds or more, or during the

C·lBfirst idle period ofat least 20 seconds after closed loop operation begins (i.e., not during an acceleration condition); not**~ithstanding,** unacceptable performance
can be determined at any time. Other monitoring conditions may be used provided the manufacturer provides a monitoring strategy and supporting data
:showing equivalent monitoring reliability and timeliness in detecting a

.

·malfunctioning sensor compared to the above monitoring conditions and the

Executive Officer approves.

(8.3.2) For secondary oxygen sensors used for catalyst monitoring and/orfuel system trim, the manufacturer shall define appropriate operating conditions for response rate and/or outputvoltage malfunction monitoring·shall be monitored for malfunction, subjectto the limitation that the monitoring conditions shall be encountered at least once during the first enaine start portion ofthe aoplicable FTP test. The monitoring system**sh~ll** operate at !east once perdriving cycle during which the manufacturer-defined monitoring conditions are met pertrip.
(8.3.3) For heated oxygen sensors, the manufacturer shall define appropriate operating conditions for malfunction monitoring ofthe heater circuit shall be monitored for malfunction, subjectto the limitation that the monitoring conditions shall be encountered at least once during the first engine start portion ofthe applicable FTP test. The monitoring system shall operate at least once perdriving cycle duringwhich the manufacturer-defined monitoring conditions are met pertrip.
(8.4) MIL Illumination and Fault Code Storage: Upon detection ofany oxygen sensor malfunction, the diagnostic system shall store a fault code and the MIL shall illuminate
no laterthan the end ofthe nexttrip ifthe malfunction is again present driving cycle during which monitoring occurs provided the malfunction is again present.
(8.5) Other (non-lambda) Oxygen Sensors:
(8.5.1) Forvehicles equipped with universal exhaust gas oxygen sensors (i.e. sensors which provide an output proportional to exhaust gas oxygen concentration), the manufacturer shall define aporopriate operating conditions for the diagnostic system shall provide to perform a response rate check (the time required to respond to a specific change in fuel/air ratio). subiect to the !imitation that the monitoring conditions shall be encountered

## a: least once durina the first engine start portion ofthe applicable FTP test. The monitoring svstem shall ooerate at least once per driving cycle during which the manufacturer-defined monitoring conditions are met. per trip and an The diaanostic-system shall also periorm an out-of-range checkforwhich monitoring shall be continuous. For malfunctions, MIL illumination and fault code storage shall be as in (8.4).
(8.5.2)· Ifa manufacturer:utilizes other**type~** ofoxygen sensors, the m·anufacturer shall submit a monitoring plan to the Executive Officerfor approval based on equivalent monitoring with conventional sensors.

C·19(9.0) EXHAUST GAS RECIRCULATION (EGR) SYSTEM MONITORING
(9.1) Requirement:

.(9.1.1) The diagnostic system shall monitorthe EGR system on vehicles so-equipped for low and high flow rate malfunctions.
(9.1.2) Manufacturers may request Executive Officerapproval to temporarily disable the EGR system check underspecific conditions 

### ifit san be providedthe manufacturer submits data and/oran engineering evaluation which adequately demonstrateS.that a reliable checkcannot be made when these conditions exist.
(9.2) Malfunction Criteria: The EGR system shall be considered malfunctioning when one or

· both ofthe following occurs: (1) any component ofthe system fails to perform within

manufacturer speCifications, or (2) the EGR flow rate exceeds the manufacturer's specified lowor high flow limits such that avehicle would exceed 1.5times any ofthe applicable FTP emission standards.
(9.3) Monitoring Conditions: The diagnostic system Manufacturers shall define appropriate ooerating conditionsfor monitoring the·EGR system. subjectto the limitation thatthe monitoring conditions shall be encountered at least once during the first engine start portion ofthe applicable FTP test monitorthe EGR system at least once pertrip. The monitoring system shall operate at leastonce perdriving cycle during which the manufacturer-defined monitoring conditions are met.
(9.4) MIL Illumination and Fault Code Storage: The diagnosticsystem shall store afault codeandthe MIL shall illuminate no laterthan the end ofthe nextdriving cycle during which monitoring occurs provided**~**the malfunction is again present.
(10.0) COMPREHENSIVE COMPONENT MONITORING
(10.1) Requirement The diagnostic system shall monitorfor malfunction any electronic powertrain component/system not otherwise described above which either provides inoutto (directly orindirectly), or receives commands from the on-board computer. andwhich: (1) can affect emissions during any reasonable in-use driving condition. or (2) is used as part ofthe diagnostic strategy for any other monitored system or comoonent.
(10.1.1) Input Components:

(f:.,) The diagnostic system shall monitorfor malfunction any electronic powertrain ccmponontlsystem which can affect emissions not otherwise described above and wr.ish provides input dir.ect_ly or**in9i~ectly** to the on board compufer.

The monitoring system shall have the capability 

### o(detecting, at a minimum, lack ofcircuit continuity and out of**rang~**values to ensure proper operation ofthe input device. The determination of out of range values shall include logic evaluation ofavailable information to determine if a component is operating within

C-20_its normal range (e.g., a"low throttle position sensorvoltage would not be reasonable at a high engine speed with a hiah mass airflow sensor**reading).~** indicating a malfunction in the case of high fuel tank pressure when the coolant temperature is lo•N; an accelerometer output indicating continuous rough road conditions, etc.).
fG1{ID Input components may include, but are not limited to, the vehicle speed sensor, crank angle sensor, knock sensor, throttle position sensor, coolanttemperature se.nsor, cam position sensor, fuel composition sensor (e.g. methanol flexible fuel vehicles), transmission electronic components such as sensors, modules, and solenoids which provide signals to the powertrain control system (see section (b) (10.5)).
fQ-j{Q The coolant temperature sensorshall be monitored for achieving a stabilized minimum temperature level which is neededto achieve closed-lqop operationJQr for diesel applications, the minimum temperature needed forwarmed-up fuel control to begin) within a manufacturer-specified time interval afterstarting the engine. The time interval shall be a function ofstarting'engine coolant temperature and/or a function of intake airtemperature. Manufacturers shall provide data to support specified times. The Executive Officershall allow disablement ofthis check underextremely low ambienttemperature conditions provided a manufacturer submits data and/oran engineering evaluation which adequately demonstrat!2_iAg- non-attainment ofa stabilized minimum temperature.
(10.1.2) OtJtput Components:
(A) The diagnostic system shall monitor output components for properfunctional response to computer commands. for properfunctional response to each computer command, any powertrain output componenUsystem ·receiving commands from the computer either directly or indirectly which can affect emissions and which is not otherv,rise monitored as a component'system in the above monitoring requirements.
(8) Components for which functional monitoring is notfeasible shall be monitored, at a minimum, for proper circuit continuity and out·of range values, ifapplicable.
(C) Output components may include, but are net limited to, the automatic idle speed motor. emission-related electronic only transmission controls, heated fuel preparation systems, the wait-to-start lamp on diesel applications. and a warmup catalyst

· bypass valve (see section (b) (10.5)).
(10.2) Malfunction Criteria:
(10.2.1) Input Components: Input components/systems shall be considered malfunctioning when, at a minimum, lack ofcircuit continuity or manufacturer-specified out-of-range values occur. Additionally, the coolant**tompe~ature** sensor shall be considered**ma!~:.:nctioning** if it does not achieve a stabilized minimum temperature nebessary**f:~** closed loop operation 'Nithin a manufa:turer specified time inter.'al after**s:c:~ing** the engine.

C-21(10.2.2) Output Components: Output components/systems shall be considered malfunctioning when a properfunctional response to**~** computer commands does not occur. Should a functional checkfor malfunction not be feasible, thenan output component/system shall be considered malfunctioning when, at a minimum, lack ofcircuitcontinuity or manufacturer-specified out-of-range values
occur.
(10.3) Monitoring Conditions: Components/systems in this subsection shall be monitored continblously.
(10.3.1) Input Components: Input components shall be monitored continuously for proper range ofvalues·and circuit continuity. For rationality monitoring (where applicable). manufacturers shall define appropriate operating conditions during which monitoring shall occur. subjectto the limitation thatthe monitoring conditions shall be encountered at leastonce during the first engine start portion ofthe applicable FTP test. Rationality monitoring shall qccurat least once per driving cycle during which the manufacturer-defined monitoring conditions are met.
(10.3.2) Output Components: Monitoring for circuit continuity and proper range ofvalues (if applicable) shall be conducted continuously. Forfunctional monitoring, manufacturers shall define appropriate operating conditions during which monitoring shaH occur. subjectto the limitation thatthe monitoring conditions shall be·encountered at least once during the first engine start portion ofthe applicable FTP test. However. functional monitoring may be conducted during non-FTP driving conditions. subjectto Executive Officer"approval. ifthe manufacturer provides data and/oran engineering evaluation which adequately demonstrate thatthe component does not normallyfunction. or monitoring**~** otherwise notfeasible. during applicable FTP test driving conditions. Functional monitoringshall occurat least once perdriving cycle during which the manufacturer-defined monitoring conditions are met.
(10.4) MIL Illumination and Fault Code Storage: Upon detecting a malfunction, the diagnostic system shall store afault code and the MIL shall illuminate no laterthan the end ofthe next driving cycle during which monitoring occurs provided**~the** malfunction is again detected.
(10.5) Component Determination: The manufacturer shall determine whethera pqwertrain input oroutput component not otherwise covered can affect emissions. Ifthe Executive Officer reasonably believes that a manufacturer has incorrectly determined that a component cannot affect emissions, the Executive Officershall require the manufacturerto provide emission data showing that such a component, when faulty and installed in a suitable testvehicle, does not have an emission effect. Emission data may be requested for any reasonable driving condition.

C-22(c) ADDITIONAL MIL ILLUMINATION AND FAULT CODE STORAGE PROTOCOL
(1.0) MIL ILLUMINATION For all emission-related components/systems, upon final determination ofmalfunction, the MIL shall remain· continuously illuminated (except that it shall blink as indicated previously for misfire detection). Ifanymalfunctions are identified in addition to misfire, the misfire condition shall take precedence, and the MIL shall blink accordingly. The diagnostic system shall store afault code for MIL iiJumination wheneverthe MIL is illuminated. The diagnostic system shall illuminate the MIL and shall store a code wheneverthe engine control powertrain enters a default or "limp home" mode ofoperation. The diagnosticsystem shall illuminate the MIL and shall store a code wheneverthe engine control system fails to enterclosed-loop operation (ifemployed) within a manufacturer specified minimum time interval.
(2.0) EXTINGUISHING THE MIL
(2.1) Misfire and Fuel System Malfunctions: For mi.sfire orfuel system malfu.nctions, the MIL may be extinguished ifthe fault does not recur when monitored during three subsequent sequential driving cycles in which conditions are similarto those underwhich the malfunction was first determined (see sections (b) (3.4.3) and (b)(7.4.3)).
(2.2) All Other Malfunctions: Except as noted in section (b) (6.4), for all otherfaults, the MIL may be extinguished afterthree subsequent sequential driving cycles during which the monitoring system responsible for illuminating the MIL functions without detectingthe malfunction trips in which the malfunction has not recurred and

## 1fno other malfunction has been identified thatwould independently illuminate.the MIL according to the requirements outlined above.
(3.0) ERASING A FAULT CODE The diagnostic system may erase a fault code ifthe same fault is not re-registered in at least40 engine warm-up cycles, and the MIL is not illuminated forthatfault code.
(d) TAMPERING PROTECTION Computer-coded engine operating parameters shall not be changeable withoutthe use ofspecialized tools and procedures (e.g. soldered or potted computer components or sealed (or soldered) computer enclosures). Subjectto ExecutiveOfficer approval, manufacturers may exempt from this requirement those product lines which are unlikelyto require protectior.. Criteria to be evaluated in making
an exemption include, but are not limited to, current availability ofperformance chips, high performance capability ofthe vehicle, and sales volume. Manufacturers using reproarammable computer code systems (e.g., EEPROM) shall employ proven methods to deter unauthorized reprogramming which may include copyrightable executable routines or other methods. Beginning with the 1999 model year. manufacturers shall include enhanced tamper protection strategies including data encryption using methods to secure the encryption algorithm. and write protectfeatures requirina electronic access to an off-site computer maintained by the manufacturer. Equivalent methods shall also be considered by the Executive Officer. Any**rep:-og~ammable** computer code system (e.g. EEPROM) shall include proven write**protec~** f.catures \lo'hich may include copyrightable executable routines or othermethods.

C·23(e) READINESS/FUNCTION CODE The en-board computer shall store a code upon first completing#'afull diagnostic check (i.e., the minimum number.ofchecks necessary for MIL illumination) ofall monitored components and systems (except as noted**below~** Ra.s not been completed since the computer memory was last cleared {e.g., through the use ofa scan tool or battery disconnect)., the manufacturer shall store a code indicating the need for additional mixed city and highway driving to complete the check

..The code shall be stored in the format specified by SAE J1979 orSAE J1939. whichever applies. Both documents are incorporated by reference in sections (k)(2.0) and (k)(5.0). The diagnosticsystem checkfor comprehensive component monitoring and continuous monitoriCig ofmisfire and fuel system faults shall be considered complete for purposes ofdetermining the readiness indication·ifmalfunctions are not detected in these areas by the time all'otherdiagnosticsystem checks are complete. Ifmonitoring is temporarily disabled underconditions which may lead to false codes for any system, that check shall not be considered in determining diagnostic system readiness. For evaporative system monitoring, the readiness indication shall be set when afull diagnostic check has been completed with respect to the**O.O~Q** inch orifice malfunction criteria ifthe monitoring conditions are constrained with respect to detection a 0.020 inch leak {see sections (b)(4.2.2) and {4.3). The diagnostic system shall also include a code or acknowledge message indicating that the diagnostic system itself is functioning properly.
(f) STORED ENGINE CONDITIONS Upon detection ofthefirst malfunction ofany component orsystem, "freeze frame" engine conditions present atthe time shall be stored in computer memory. Should a subsequentfuel system or misfire malfunction occur, any previously stored freeze frame conditions shall be replaced bythe fuel system or misfire conditions (whichever occurs first). Stored engine condition's shall include, but are not limited to, calculated load value, engine RPM, fuel trim value(s)

### ill available), fuel pressure (ifavailable), vehicle speed (if available), coolant temperature, intake manifold pressure (if available), closed- oropen-loop operation (ifavailable), and the fault code which caused the data to be stored. The manufacturer shall choose the most appropriate set ofconditions facilitating effective repairs forfreeze frame storage. Only one frame ofdata is required. Manufacturers may at theirdiscretion choose to store additional frames provided that at**l~ast** the required frame can be read by a generic scan tool meeting SAE specifications established in SAE Recommended Practices on "OBD II Scan Tool" (J1978), Maret: :':'92 June. 1994, and "E/E Diagnostic Test Modes" (Ji979), December 1001 June. 1994. which are incorporated by reference herein. Ifapproval is granted to use the SAE J1939 communication protocol according to section (k)(5.0), the data shall be accessible using a scan tool meeting the J1939 specifications. Ifthe fault code causing the conditions to be stored is erased in accordance with section (c) (3.0), the stored engine conditions may be cleared as well.
(g) DURABILITY DEMONSTRATION VEHICLE
(1.0) REQUIREMENT Each year a manufacturer shall provide emission test data obtained from a certification durability vehicle for Ot"Je enainefamily certification durability vehicle that has not been used previously for purposes ofthis section. Ifa manufacturer does not have a certification durability vehicle available which is suitable for this demonstration. T!he Executive Officer shall permit a manufacturer to satisfy this

C-24requirement with waive this requirement ifa manufacturer doec not have a certification durability vehicle available which ic suitable forthis demonstration in a given year, provided a manufacturer submits other data from a representative high mileage vehicle
orvehicles (or a representative high operating-hour engine orengines) acceptable to the Executive Officerto demonstrate that malfunction criteria are based on emission performance. The Air Re-sources Board (ARB) shall determine the demonstration '<'Chicle engine family to be demonstrated. Each manufacturer shall notify the Executive Officer priorto running a California durability vehicle in order to allow possible selection
as the demonstration vehicle for a given model year unless avehicle h?s previously been chosen forthe given model year applying for certification ofthe enqin·e families planned for a particular model year in orderto allow selection ofthe engine family to be demonstrated. Demonstration tests shall be conducted·on the certification durability vehicle orengine at the end ofthe required mileage oroperating-hour accumulation. For non-LEVs, until a NOx standard applicablefor more than 50,000 miles is established in California, the federal 50,000 to 100,000 mile NOx standard shall be used for**demonstra~ion** purposes. (1.1) Flexible fuel vehicles shall perform each demonstration test usil'lg 85 percent methanol and 15 percent gasoline, ahd gasoline only. Forvehicles capable ofoperating on other fuel combinations, the manufacturer shall submit a plan for performing demonstration testing for approval by the Executive Officer on the basis of providing accurate and timely evaluation ofthe monitored systems.
(2.0)**APPLICABILITY~** The manufacturer shall perform single-fault testing based on the applicable FTP test cycle with the following components/systems at their malfunction criteria limits as determined by the manufacturer:
(2.1) Oxygen Sensors: The manufacturer shall conductthe following demonstration tests: The first test involves testing all primary and secondary (ifequipped) oxygen sensors used for fuel control simultaneously possessing normal outputvoltage but response rate deteriorated to the malfunction criteria limit (secondary oxygen sensors forwhich response rate is not monitored shall be with normal response characteristics). The second test shall include testing with all primary and secondary (if equipped) oxygen sensors used fo·r fuel control simultaneously possessing output voltage at the malfunction criteria limit. Manufacturers shall also conduct a malfunction criteria demonstration test for any other oxygen sensor parameter that can cause vehicle emissions to exceed 1.5 times the applicable standards (e.g., shift in air/fuel ratio at which oxygen sensor switches). When performing additional test(s), all primary and secondary (if equipped) oxygen sensors used forfuel control shall be operating at the malfunction criteria limit forthe applicable parameter only. All other primary and secondary oxygen sensor parameters shall be with normal characteristics. The Executive Officer may approve other demonstration protocols ifthe manufacturer can adequately show comparable assurance that the malfunction criteria are chosen based
on meeting emission requirements.
(2.2) EGR System: The manufacturer shall conduct only one flow rate demonstration test at the lowflow limit.

C-25(2.3) Fuel Metering System:
(2.3.1) For vehicles with short-term or long-term fuel trim circuitry, the manufacturer shall conduct one demonstration test atthe border ofthe rich limit and one demonstration test at the border"ofthe lean limit established bythe manufacturer for emission compliance.
(2.3.2) For other systems, the manufacturer shall conduct a demonstration test at the criteria limit(s).
"(2.3.3) For purposes ofthe demonstration, the fault(s) induced may result in a uniform distribution offuel and airamong the cylinders. Non-uniform distribution offuel and air used to induce afault shall not cause an indication ofmisfire. The manufacturer shall describe the fault(s) induced in the fuel system causing it to operate at the criteria limit(s) for the demonstration test (e.g., restricted or increased flowfuel injectors, an altered output signal airflow meter, etc.). Computer modifications to cause the fuel system to operate at the adaptive limit for malfunction shall not be allowed for the demonstration tests.
(2.4) Misfire: The manufacturer shall conduct one FTP demonstration test atthe criteria limit specified in (b)(3.2)(8) for malfunction and a second demonstration test showing that the vehicle is capable ofpassing a California l.flspection/Maintenance testwhen operating at the misfire criteria limit. This demonstration is not required fordiesel applications.
(2.5) SecondaryAir System: The manufacturer.shall conduct aflow rate demonstration test at the lowflow limit, unless onlya functional check is permitted according to section (b)(5.2.2).
(2.6) Catalyst Efficiency:
(2.6.1) Non-Low Emission Vehicles: The manufacturer shall conduct a baseline FTP test with a representative 4000 mile catalystfollowed by one FTP demonstration test using a catalyst system deteriorated to its malfunction limit. Ifa manufacturer is employing asteady state catalyst efficiency check in accordance with section (b) (1.2.4), demonstration ofthe catalyst monitoring system is not required.
(2.6.2) Low Emission Vehicles: The manufacturer shall conduct a cata·lyst effteiency demonstration using a catalyst system deteriorated to**~**the malfunction criteria. Iftwo substrates are integrated into the same container, o.nly the upstream substrate shall be deteriorated for !he demonstration.
(2.7) Heated Catalyst Systems: Forheated catalyst sys::ms that use an af:ter start heating strategy, tThe manufacturer shall conduct a demonstration test where the designated heating temperature is reached at the time limit for malfunction after engine starting.

C·26(2.8) Manufacturers may electronically simulate deteriorated components, but may not make anyvehicle control unit modifications when performing demonstration tests. All equipment necessary to duplicate-the demonstration test must be made available to the ARB upon request. · (3·.0) PRECONDITIONING The manufacturer**s~all** use the first engine start portion of one applicable FTP cycle for preconditioning before each ofthe above emission tests. If a manufacturer Ga-A-provides data and/oran engineering evaluation which adequately demonstrate that additional preconditioning is necessaryto stabilize the emission control system, the Executive Officershall allow an additional identical preconditioning cycle, ora Federal Highway Fuel Economy Driving Cycle, following aten-minute (or 20 minutes for medium duty engines certified on an engine dynamometer) hot soak after the initial preconditioning cycle. A cold start shall not be required prior to conducting preconditioning cycles.
(4.0) EVALUATION PROTOCOL
(4.1) 'A':"th the exception ofshortterm trim only vehicles, tihe manufacturer shall set-the system or**compo~ent** forwhich detection isto be demonstrated at the criteria limit(s) from the beginning ofand thro,ughout the priorto conducting the applicable preconditioning cycle{§l and FTP te.st. (For misfire demonstration. misfire shall be set at its criteria limitas specified pursuant to section {b)(3.2){8)). Ifa second preconditioning cycle is permitted in accordance with section {3.0) above, the manufacturer may adjust the demonstrated system orcomponent before conductina the second preconditioning cycle; however, the demonstrated system or component shall · not be replaced, modified oradjusted after precof.lditioning has taken place.

(4.2) Fe:- short term trim only vehicles, the fuel system shall operate at the criteria limit from the beginning ofclosed loop operation forthe manufacturer defined time interval for de:armining malfunction (and normally otherwise) for both the applicable preconditioning and FTP test cycles.· After preconditioning, the vehicle shall be operated over the first en:Jine start portion ofthe applicable FTP test to allowforthe initial detection ofthe malfunction. This driving cycle may be omitted from the evaluation protocol if it is**un:-~ecessarv.** If required by the demonstrated monitoring strategy. a cold soak may be**oe~ormed** priorto conducting this driving cycle.
(4.3)**rc~** misfire demonstration, misfire shall be set at its criteria limit as specified pursuant to ::::ion (b) (3.2) (8) throughout the applicable preconditioning cycle and FTP test. The vehicle shall then be operated over afull applicable FTP test.
(4.4) Forall demonstrations, the MIL shall be illuminated before the hot start portion ofthe full FTP test in accordance with requirements ofsubsection (b):**(4.~.1)** Ifthe MIL does not**illuminat~** when the systems or components are set at their limit(s), the criteria limit orthe 080 system is not acceptable.

C-27(4.4.2) Except for catalyst efficiency demonstration, ifthe MIL illuminates and emissions do not exceed 1.5 times any ofthe applicable FTP emission standards, no further demonstration shall be required.

. (4.4.3) Except for catalyst efficiency demonstration, ifthe MIL illuminates and emissions exceed 1.5 times any ofthe applicable FTP emission standards, the vehicle shall be retested with the component's malfunction criteria limit value reset such that vehicle emissions are reduced by no more than 30 percent. Limit value at a minimum includes, in the case ofoxygen sensors, response rate and voltage; for EGR·systems, EGR flow rate; forsecondaryairsystems, airflow rate; for short-term fuel trim- only·systems, time interval atthe fuel system range of authority limit;. for long-term fuel trim systems, shift in the base fuel calibration; for heated catalyst systems, thetime limit between engine starting and attaining the designated heating temperature.(jf an after-start heating strategy is used); and for misfire, percent misfire. Forthe 

### 080system to be approved, the vehicle must then meetthe above emission levelswhen tested with the.faulty components. The MIL shall not illuminate during this demonstration

. 

### • (4.4.4) For Non-LEV catalyst efficiency demonstration, ifHC emissions do not increase by more than 1.5 times the·standard from the baseline FTP test and the MIL is .illuminated, no further demonstration shall be required. However, ifHC emissions increase by more than 1.5times the standard from the baseline FTP test andthe MIL is illuminated, the vehicle shall be retested with the average FifP HC conversion capability ofthe catalystsystem increased by no more than 10 percent (i.e., 10 percent more engine outhydrocarbons are converted). For the 

### 080systeni to be approved, the vehicle mustthen meetthe above emission levelswhen re-tested. The MIL shall notilluminate during this demonstration.
(4.4.5) For Low Emission Vehicle catalyst efficiencydemonstration, ifHC emissions do' not exceed the applicable emission threshold specified in section (b)(1.2.2) and the MIL is illuminated. no further demonstration shall be required. However. if HC emissions exceed the threshold and the MIL is illuminated. the vehicle shall be retested with average FTP HC conversion capability ofthe catalyst system increased by no more than 5 percent (i.e

.. 5 percent more engine out hydrocarbons are converted). Forthe 

### 080II system to be approved. the vehicle must then meet the above emission levels when re-tested. The MIL shall no{ illuminate during this demonstration. ifc::talyst efficiency is within the malfunction criteria range overthe FTP test and the MIL is illuminated, no further demonstration is required. Ifcatalyst efficiency falls outside ofthe malfunction criteria range, the catalyst's efficiency shall bs adjusted, orthe catalystshall be replaced with another deteriorated catalyst, and the system re tested. Ifcatalyst efficiency is within the malfunctioncriteria range overthe

## nP test and the MIL is not illuminated, the catalyst may be deteriorated further but not belowthe lower limit ofthe malfunction criteria range, and the syS!tem retested. Ifthe catalyst's efficiency is belowthe lower limit 9:the malfunction criteria range and the MIL is not illuminated, the 

### 090system is not acceptable.

C-28(4.5) Ifan OBD system is determined unacceptable by the above criteria, the manufacturer may re-calibrate and re-test the system on the same DDV. Any affected monitoring systems demonstrated prior to the re-calibration shall be re-verified.
(h) CERTIFI.CATION**DOCUMENTATION~** The manufacturer shall submit the following documentation for each engine family at the time ofcertification. With Executive Officer approval. one or more ofthe documentation r:equirements specified in this section may be waived or altered ifthe information required would be redundant or unnecessarily burdensome to generate:
(1) A written description ofthe functional operation ofthe diagnostic system to be included in Section 8 ofmanufacturers' certification applications.
(2) A table providing the following information for each monitored component or system (either computer-sensed or -controlled) ofthe emission control system:

i. corresponding fault code ii. monitoring method or procedure for maffunction detectiron iii. primary malfunction detection parameter and its type ofoutput signal iv. fault criteria·limits used to evaluate output signal ofprimary parameter
v. other monitored secondary parameters and conditions (in engineering units) necessary for malfunction detection· vi. monitoring time length and frequency ofchecks vii. criteria for storing fault code viii. criteria for illuminating malfunction indicatorlight ix. criteria used for determining out of range values and input component rationality checks
(3) A logicflowchart describing the general method ofdetecting malfunctions for each monitored emission-related component or system. To the extent possible, abbreviations in Society ofAutomotive Engineers' (SAE) J1930 "Electrical/Electronic Systems DiagnosticTerms, Definitions, Abbreviations, and Acronyms", September,**~June.** 1993, shall be used. J1930 is incorporated by reference herein. The information required in the chart under (2) above may instead be included in this flow chart, provided all ofthe information required in (2) is included.
(4) A listing and block diagram ofthe input parame:ers used to calculate or determine calculated load values and the input parameters used to calculate or determine fuel trim values.
(5) A scale drawing ofthe MIL and the fuel cap indicator light, ifpresent, which specifies location in the instrument panel, wording, color, and intensity.
(6) Emission test data specified in subsection (g).
(7) Data supporting the selected degree ofmisfire which can be tolerated withDut damaging the catalyst

C·29(8) Data supporting the limit forthe time between engine starting and attaining the designated heatingtemperature for after-start heated catalyst systems.
(9) For Low Emission Vehicles, data supporting the criteria used by the diagnostic system for establishing a 50 to 60 pement catalysttotal HC efficiency level, or a 40 to 50 percent deteri.oration level to indicate a malfunction when catalyst deterioration
causes emissions to exceed the applicable threshold specified in section (b)(1.2.2).·
(10) For Non-Low Emission Vehicles, data supporting the criteria used to indicate a malfunction when catalyst deterioration leads to a 1.5 times the standard increase in HC emissions. Ifa steady state catalyst efficiency check is employed in accordance with section (b)(1.2.4), data supporting the criteria used bythe diagnosticsystem for establishing a 60 to 80 percent catalyst efficiency level shall be provided instead.
(11) Data supporting the criteria used to detect evaporative purge system leaks.
(12) A description ofthe modified ordeteriorated component§. used**for~**fault simulation to dri'.'e the fuel system to the criteria'limit(s) for•demonstrating fuel system compliance with**th~** requirements of with respect to the demonstration tests specified in stffisection (g).

@ A listing ofall electronic powertrain input and output siqnals.
(1J1) Any other information determined by the Executive Officerto be necessary to demonstrate compliance with the requirements ofthis section.

(i) IN-USE RECALL TESTING PROTOCOL The manufacturer shall adhere to the following procedures forvehicles subjectto in-use recall testing required bythe ARB:
(1) Ifthe MIL illuminates during atest cycle orduring a preconditioning cycle, the fault causing the illumination may be identified and repaired following published procedures readily available to the public including the independentservice sector.
(2) The test may be rerun, and the results from the repaired vehicle may be used for emission reporting purposes. (3) If avehicle contains a part which is operating outside ofdesign specifications with no MIL illumination, the part shall not be replaced prior to emission testing unless it is determined that the part has been tampered with orabused in such away that the diaanosticsystem cannot reasonably be expected to detectthe resulting malfunction

.. (4) Failure ofavehicle, orvehicles on average, to meet applicable emission standards with no illumination ofthe MIL shall not by itselfbe grounds for requiring the OBD system to be recalled for recalibration or repair since the OBD system cannot predict precisely when vehicles exceed emission standards.

C·30(5) A decision to recall the OBD system for recalibration or repair will depend on factors including, but not limited to, level ofemissions above applicable standards, presence of identifiable faulty or deteriorated components vihich affect emissions with no MIL illumination, and systematic erroneous activation ofthe MIL. With respect to
erroneous activation ofthe MIL, the manufacturer may request Executive Officer approval to take action apart from a formal recall (e.g., extended warranty or a service campaign) to correct the performance ofthe diaonostic strategy on in-use vehicles. In considerina a manufacturer's request, the Executive Officershall considerthe estimated frequency offalse MIL activation in-use, and the expected effectiveness in relation to a formal recall ofthe manufacturer's proposed corrective action in capturing vehicles in the field. For 1994 and 1995 model**years~.** on-board diagnostic systemrecall shall not be considered for excessive emissions without MIL illumination (if required) and fault code storage until emissions exceed 2.0 times any ofthe applicable standards in those instances where the malfunction criterion is based on exceeding 1.5 times any ofthe applicable standards. This hiqher·emission threshold for recall shall extend up to the 1998 model yearforTLEV applications (except for catalyst monitoring, forwhich the threshold shall extend to the 2000 model year), and to the 2000 model yearfor all applicable monitoring requirements on LEV and ULEV applications. · {§l Regarding catalyst system monitoring, unmonitored catalysts shall be normally aged.
U) CONFIRMATORY TESTING The ARB may perform confirmatory testing of .manufacturers' diagnostic systems for compliance with requirements ofthis section in accordance with malfunction criteria submitted in the manufacturer's approved certification documentation. The ARB or its designee may install appropriately deteriorated or malfunctioning components in an otherwise properly functioning test vehicle ofan engine family represented by the demonstration test vehicle(s) (or simulate a deteriorated or malfunctioning component response) in orderto testthe fuel system, misfire detection system, oxygen sensor, secondary air system, catalyst efficienGy monitoring system, heated catalyst system, and EGR system malfunction critefia**for.co~pliance** with the applicable emission constraints in this section. Confirmatory testing to verify**~hat** malfunction criteria are set for complian·ce with emission requirements ofthis section shall be limited to vehicles in engine families derived from the demonstration vehicle(s). Diagnostic systems ofa representative sample ofvehicles which uniformly fail to meet the requirements ofthis section may be recalled for correction.
(k) STANDARDIZATION Stan.dardized access to emission-related fault codes, emission-related powertrain test information (i.e., parameter values) as outlined in subsection (1), emission related diagnostic procedures, and stored freeze frame·data shall be incorporated based on the industry specifications referenced in**~his** regulation.
(1.0) Either SAE Recommended Practice J1850, "Class B Data Communication Network Interface", i\tJgust, 1991 May, 1994, or ISO 9141-2**~.** "Road·vehiclesDiagnostic Systems- CARB Requirements for Interchange of Digital Information," February. 1994, which are incorporated by**refere:~ce,** shall be used as the on-board to off-board network communications protocol. All S.-\E J1979 emission related messages sent to the J1978 scan tool over a J1250 data link shall use the Cyclic

C-31Redundancy Check and the three byte header, and shall not use inter-byte separation or checksums. · (2.0) J1978 & J1979 Standardization ofthe message content (including test modes and test messages) as well as standardization ofthe downloading protocol forfault codes, parametervalues and their units, and freeze frame data are setforth in SAE Recommended Practices on "OBD II Scan Tool" (J1978), March, 1992June. 1994, and "E/E DiagnosticTest Modes" (J1979), December, 1991 June 1994,which have been incorporated_ by reference. Fault codes, parametervalues, and freeze frame data shall be capable ofbeing downloadedto a generic scan tool meeting these SAE specifications.
(2.1) Manufacturers shall make readily available at afair and reasonable price to the automotive repair industryvehicle repair procedures which alloweffective emission related diagnosis and repairs to be performed using onlythe J1978 generic sca'n tool and commonly available, non-microprocessor based tools. _In addition to these procedures, manufacturers may publish repair procedures referencing the use of

. I manufacturerspecific or enhanced equipment. · ·

- (2.2) The J1978 scan tool shall be capable ofnotifying the userwhen one or more ofthe required monitoring systems are not included as part ofthe OBDsystem.
(3.0) J2012 Part C Uniform fault codes based on SAE specifications shall be employed. SAE "Recommended Format and Messagesfor DiagnosticTrouble Codes" (J2012), March January,

# m 1994, is incorporated by reference.
(4.0) J1962 

## Astandard data link connectorin a standard location in each vehicle based on SAE specifications shall be incorporated. The location ofthe connectorshall be easily identified by atechnician entering the vehicle from the driver's side. Any pins in the standard connectorthat provide anyelectrical power shall be properly fused to protect the integrity and usefulness ofthe diagnostic connectorfordiagnostic purposes. The SAE Recommended Practice "Diagnostic Connect_or'' (J1962), June, 1992;is incorporated by reference.

i§Jll With Executive Officer approval, medium-duty vehicles may alternatively employ the communication orotoco!s established in SAE Recommended Practice J1939 to satisfy the standardization requirements specified in sections (k)(1) throuah {k)(4) -above. The Executive Officer's decision shall be based on the effectiveness ofthe SAE J1939 protocol in satisfying the diagnostic information requirements ofSection 1968.1- in comoarison with the above referenced documents. · (I) SIGNALACCESS
(1 .0) The following signals in addition tothe required freeze frame information shall be made available on demand through the serial port on the standardized data link connector: calculated load value, diagnostictrouble codes, engine coolant 

### • temperature. fuel control system status (open loop, closed loop, other; ifequipped with closed loop fuel control), fuel trim (if equipped), fuel pressure (if available),

C-32ignition timing advance (if equipped), intake airtemperature (ifequipped), manifold air pressure (ifequipped), airflow rate from mass airflow meter (if equipped), engine RPM, throttle position sensor output value (if equipped), secondary air status (upstream, downstream, or atmosphere; ifequipped), and vehicle speed (ifequipped). The signals shall be provided in standard units based on the SAE specifications incorporated by reference in this regulation, and actual signals shall be clearly identified separately from defaultvalue or limp home signals.
(2.0) The manufacturer shall publish in factory service.manuals a normal range forthe calculated load value and mass airflow rate (ifavailable) at idle, and at 2500 RPM (no load, in neutral orpark). If2500 RPM is outside ofthe operating range ofthe engine, the corresponding data may be omitted. Ifthe total fuel command trim is made up by more than one source (e.g. short-term trim and long-term trim), all fuel trim signals shall be available. The signals shall be provided in standard units based
on the incorporated SAE specifications, and actual signals shall be clearly identified separately from defaultvalue or limp home signals. Diesel vehicles shall be exempt from this requirement.
(3.0) Oxygen sensor data that will allow diagnosis ofmalfunctioning oxygen sensors shall be provided through serial data port on the standardized data link. In addition, beginning with the 1996 model year (with full comoliance required by the 1997 model year), for all monitored components and systems, except misfire detection, fuel system monitoring, and comprehensive component monitoring), results ofthe most recent test performed bythe vehicle, and the limits to which the**syste~** is compared (except for continuously monitored systems/components) shall be available thro.ugh the serial data port on the standar.dized data link connector. Forthe monitored

· components and systems excepted above. a pass/fail indication forthe most recent

test results shall be available through the data link. Such data shall be transmitted in accordance with SAE J19.79 (or SAE J1939, whicheverapplies). Alternative methods shall be approved by the Executive Officer if, in thejudgment ofthe Executive Officer, they provide for equivalent off-board evaluation.
(m) IMPLEMENTATION SCHEDULE

(1 0) These OBD II requirements, except evaporative purge system monitoring (see section (b) ('1 1.5)) unless otherwise soecified, shall be implemented beginning with the 1994 model year.
(2 0) The Execut1ve Officer shall grant an extension for**complian~e** with the requirements of these subsections with respect to a specific vehicle model orengine family if"the vehicle model or engine family meets previously applicable on-board diagnostic system requirements and a manufacturer demonstrates that it cannot modify a prese11t electronic control system by the 1994 model-year because majo_r design system changes not consistentwith·the manufacturer's projected changeoverschedule would be needed to comply with provisions ofthese subsections.
(2 1) The manufacturer which has received arfextension from the Executive Officer shall comply with these regulations when modification ofthe electronic system occurs in

C:33 

# •accordance with the manufacturer's projected changeover schedule or in the 1996 model year, whicheverfirst occurs. (2.2) Any manufacturer requesting an extension shall, no laterthan October 15, 1991, submit to the Executive Officer an application specifying the period for which the extension is required.
(3.0) Small volume manufacturers as defined in (n) (13.0) shall meetthese requirements by the 1996 model year. · (4.0) Manufacturersmay attheirdiscretion implement-a portion ofthese regulations prior to the required implementation date provided thatthe system complies with previously applicable on-board diagnosticsystem requirements.

• (5.0) Vehicles certified to run en alternate fuels, and dDiesel vehicles; shall meet these requirements by the 1996 model year. Manufacturers may request a delay in the implementation ofthese requirements fordieselvehicles until,1997, subject to Executive Officer approval, ifit is adequately demonstrated thatthe delay will allowfor the development ofsignificantly more effective monitoring systems.

. .(§Jl Vehicles certified to run on alternate fuels shall meet these requirements by the 1996 model year. However. manufacturers may requestthe Executive Officertowaive specific monitoring requirements forwhich monitoring may not be reliable with respect to the use ofalternate fuels untilthe 1999 modelyear
f§.1l Medium-duty vehicles with engines certified on anengine dynamometer may comply with these requirements on an engine model yearcertification basis ratherthan on a vehicle model basis. ' I
(6.0) The Executive Officer may waive one ormore ofthe requirements ofthese subsections with respectto a specificvehicle orengine family forwhich production
commences prior to April 1, 1994, and which is not otherwise exempted from compliance in accordance with sections (2.0) and (2.1) above. In granting awaiver, the Executive Officer shall considerthe following factors: the extentto which these requirements are satisfied overall on the vehicle applications in question, the extentto which the resultant diagnostic system design will be more effective than systems developed according to section 1968, Title 13, and a demonstrated good-faith effort to meet these requirements in full by evaluating and considering the best available monitoring technology.
(6.1) For 1995 arid 1996 model yearvehiclesforwhich production is to commence subsequentto March 31, 1994, and which are notexempted from compliance in accordance with sections (2.0) and (2,1) above, the Executive Officer, upon**r~ceipt** of
an application from the manufacfurer, may certify the vehicles in question even though said vehicles may not comply with one or more ofthe requirements ofthese subsections. Such certification is continQent uponthe manufacturer meeting the criteria set forth in section (6.0) above. Manufacturers of non-complying systems shall be subject to fines pursuant to section 43016 ofthe California Health and Safety Code

C-34for each deficiency identified, afterthe second, in avehicle model. For the third deficiency and every deficiencythereafter identified in avehicle model, the fines shall be in the amOunt of$50 perdeficiency pervehicle for non-compliance with any ofthe _monitoring requirements specified in subsections (b)(1) through (b)(9), and $25 per deficiency pervehicle for non-compliance with any ·other requirement ofsection 1968.1. In determining the identified order ofdeficiencies, deficiencies ofsubsections (b)(1) through (b)(9) shall be identified first. Total fines pervehicle underthis section shall not exceed $500 pervehicle and shall be payable to the State Treasurer for deposit in the Air Pollution Control Fund. Engine families in receipt ofa waiver granted undersection (6.0) above shall be exempt from these fines. Further, small volume manufacturers choosing to comply with these requirements in the 1995 model year shall also be exempt from these fines. For 1996 model yearvehicles and engines only, failure to properly monitor multiple electronic transmission components shall be considered a single monitoring system deficiency.

@.1.1 Beginning with the 1997 model yearand throuah the 2000 model. the certification provisions set forth in section (m)(6.1) above shall continue to apply subject to the following limitations: 1) The specified fines shall apply to the second and subsequentl'l identified deficiencies, with the exception that fines shall applyto all monitoring system deficiencies wherein a required monitoring strategy is completely absent from the 080system, and 2) Manufacturers may not carry over monitoring system deficiencies to future model years unless it can be demonstrated that vehicle hardware modifications would be necessaryto correct the deficiency, in which case the deficiency may be carried overforone modelyear.

(n) GLOSSARY For purposes ofthis section:
(1.0) "Malfunction" means the inability ofan emission-related component orsystem to remain within design specifications. Further, malfunction refers to the deterioration of any ofthe above components orsystems to a degree that would likely cause the emissions ofan average certification durability vehicle with the deteriorated components or systems present at the beginning ofthe applicable certification emission test to exceed by more than 1.5 times any ofthe emission standards (both with resoect to the certificat'ion and useful life standards), unless otherwise specified, appli.cable pursuant to Subchapter 1 (commencing with Section 1900), Chapter 3 of Title 13. · (2 0) "Secondary air" refers to air introduced into the exhaust system by means ofa pump or aspirator valve or other means that is intended to aid in the oxidation of HC and

- CO contained in the exhaust gas stream.
(3 0) "Engine misfire" means lack ofcombustion in the cylinder due to absence ofspark, poorfuel metering, poorcompression, or any other cause. · (4 0) Oxygen sensor "response rate" refers to the delay (measured in milliseconds) between a switch ofthe sensorfrom lean to rich or vice versa in response to a change in fuel/air ratio above and below stoichiometric.

C·35(5.0) A "trip" means vehicle operation (following.an engine-off period) ofduration and driving mode such that all components and systems are monitored at least once by the diagnostiC: system except catalyst efficiency or evaporative system monitoring when a steady-speed check is used, subject to the limitation that the manufacturer-defined trip monitoring conditions shall all be encountered at least once during the first engine start portion ofthe applicable FTP cycle.
(6.0) A "warm-up cycle" means sufficientvehicle operation such that the coolant temperature**h;:~s** risen by at least40 degrees Fahrenheit from engine starting and reaches a minimum temperature pf 160 degrees Fahrenheit.
(7.0) A "driving cycle" consists ofengine startup, vehicle operationbeyond the beginning of closed loop operation, andengine shutoff. · · (8.0) "Continuous monitoring" means sampling at a rate no less than two samples per second. Iffor engine control purposes, a computer input component is sampled less frequently, the value ofthe component may instead be evaluated each time sampling

(9.0) · occurs.

"Fuel trim" refers to feedback adjus.tments to the base fuel schedule. Short-term fuel trim refers to dynamic or instantaneous adjustments. Long-term fuel trim refers to · much more gradual adjustments to the fuel calibration schedule than short-term trim adjustments. These long term adjustments compensate forvehicle differences and gradual changes that occurovertime.
(10.0) "Base Fuel Schedule" refers to the fuel calibration schedule programmed into the Powertrain Control Module or PROM when manufactured orwhen updated by some off-board source, priorto any learned on-board correction.
(11.0) "Calculated loadvalue" refers to an indication ofthe current airflow divided by peak airflow, where peak airflow is corrected for altitude, ifavailable. This definition provides a unitless numberthat is not engine specific, and provides the service technician with an indication ofthe percent engine capacity that is being used (with wide open throttle as 100%). ·
Current Airflow Atm Pressure (@ sea level) CLV

## = X Peak airflow (@ sea level) Barometric pressure

For diesel aoplications, the calculated loadvalue shall be determined bythe ratio of current outputtorgue to maximum output torgue at current engine speed.
(12.0) "Medium-duty vehicle" is defined in Title 1**~.** Section 1900 (b)(9).
(13.0) "Small volume manufacturer" shall mean any vehicle manufacturer with sales less than or equal to 3000 new light-duty veh'!clesand medium-duty vehicles per model year based on the average number ofvehicles sold by the manufacturer each model yearfrom 1989 to 1991. For manufacturers certifying for the first time in California,

C·36model yearsales shall be based on projected California sales.
(14.0) "Low Emission Vehicle" refers to a vehicle certified in California as a Transitional Low Emission Vehicle (TLEV), a Low Emission Vehicle (LEV), or an Ultra**Lo~** Er.nission Vehicle (ULEV). These vehicle catego_ries are further defined in Titte 13, sections 1956.8 and 1960.1.
(15.0) "Diesel engines'\ forthe purposes ofthese regulations, includes diesel derived refers i.Q_engines and those using a compression ignition thermodynamic cycle.
(16.0) "Functional check"foran output component means verification ofproper response to
a computer command. Foran input component, functional check means verification ofthe input signal being in the range ofnormal operation, including evaluation ofthe sign<:ll's rationality in comparison to all available information.
(17.0) "Federal Test Procedure" (FTP) cycle ortest refer:s to, for passengervehicles, light-dutytrucks, and medium-duty vehicles certified on a chassis dynamometer, the driving schedule in Code of Federal Regulations (CFR) 40, Appendix 1, Part 86, section (a) entitled, "EPA Urban Dynamometer Driving Schedulefor Light- Duty Vehicles and Light-Duty Trucks." For medium-duty engines certified on an engine dynamometer, FTP cycle ortest refers to the engine dynamometer schedule in CFR 40, Appendix 1, Part 86, section (f)(1), entitled, "EPA Engine Dynamometer Schedule for Heavy-Duty Otto-Cycle Engines," or section (f)(2), entitled, "EPA Engine Dynamometer Schedule for Heavy-Duty Diesel Engines."
l..1.§Jll "Redline enaine speed" means the manufacturer recommended maximum engine speed as normally displayed on instrument paneltachometers, orthe engine speed at which fuel shutoffoccurs

.



### .L1ELQl "PowerTake-Off unit" refers to an engine driven output provision forthe purposes of powering auxiliary equipment (e.g

.. a dump-truck bed, aerial bucket. ortow-truck winch).

Note Authority cited. Sections 39600, 39601, 43013 and 43018, Health and Safety Code. Reference: Sections 39002,39003,43013,43100,43101,43102,43104,43105 and 43204. Health and Safety Code.

C-37

### APPENDIX D

Modifications to Sections 203.0, 2031, and the incorporated certification proc"edures, "California Certification and Installation Procedures for Alternative Fuel Retrofit Systems for Motor Vehicles Certified for 1994 and Subsequent Model

## X ears.

Note: Theproposed amendments are shown in underline to indicate additions to the sections and strikeoutto indicate deletions.

# . ,,

### Amend Title 13, California Code of Regulations, Sect-ions 2030 and 2031, to read as follows:
Article 5. Approval of Systems Designed to Convert Motor Vehicles to Use Fuels Other Than the Original Certification Fuel
2030. liquefied Petroleum Gas or Natural Gas Retrofit Systems. (a) Applicable Standards and Test Procedures.
The.standards and test procedures for approval of systems designed to convert 1993 and earlier model year motor vehicles to use liquefied petroleum gas or natural gas fuels are contained in "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use Liquefied Petroleum Gas or Natural Gas Fuels" adopted by the State Board on April 16, 1975, as amended March 11, 1993. The standards and test procedures for approvai of systems designed to convert 1994 and**subsequ~nt** 

### model year motor**vehicl~s** 

### to use liquefied petroleum gas or natural gas fuels are contained in "California Certification and Installation Procedures for Alternative Fuel Retrofit Sysfems for Motor Vehicles**Cert~fied** 

### for 1994 and Subsequent Model Years," adopted by the State Board March 11, 1993, ll_ 

### amended At the option of the retrofit system manufacturer, the standards and test procedures for approval of systems designed to convert 1994 and subsequent model year vehicles to use liquefied petroleum gas or natural gas fuels may be used for approval of systems designed to convert 1993 and earlier model year motor vehicles to use liquefied petroleum gas or natural gas fuels in lieu of the "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use liquefied Petroleum Gas or Natural Gas Fuels." {b) Implementation Phase-In Schedule. Notwithstanding subsection (a), a retrofit system manufacturer may apply "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use Liquefied Petroleum Gas or Natural Gas Fuels" to certify retrofit systems for**199~** 

### and 1995 model-year vehicles in accordance with the follcwing implementation phase-in schedule. Each manufacturer may certify a maximum of 85 percent of its total 1994 model-year engine family retrofit systems and 45 percent of its total 1995 model-year systems according to the requirements of these test procedures and "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use A1 

### coho 1 

### or A 1



### coho 1 

### /Gaso1

### ine Fue1

### s", adopted by the State Bo·ard on Apri1 

### 28, 1983, as amended March 11, 1993. The remaining percentage of each**manufactu~er's** 

### certified 1994 and 1995 model-year engine family retrofit systems and all of 1996 and subsequent model-year engine family retrofit systems**s~all** 

### be certified according to."California Certification and Installatlon Procedures for Alternative Fuel Retrofit Systems For Motor

### Vehicles Certified For 1994 and Subsequent Model Years." The percentages shall be determined from the total**number~:** 

### retrofit systems certified and shall be met prior to the end of the applicable calendar year. "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use Liquefied Petroleum Gas or Natural Gas Fuels" shall not Qe applied to certify a a retrofit system for installation on a transitional low-emission vehicle ("TLEV"), low-emission vehicle ("LEV"), or ultra-low-emission vehicle ("ULEV") or to certify a retrofit system designed to convert a vehicle to TLEV, LEV, 6r ULEV emission standards (a& defined in 

### Section 1960.1, Title 13, California.Code of Regulations).
NOTE: Authority cited: Sections 39515, 39600, 39601 and 43006, Health and Safety Code; Sections 27156 and 38395, Vehicle Code. Reference: Sections 43000, 43004, 43006, 43008.6, 43013 and**43018~** 

### Health and Safety Code; Sections 27156, 38391 and 38395, Vehicle Code.

• 

### 2031. Alcohol or-Alcohol/Gasoline Fuels Retrofit Systems. (a)**Appli~able** 

### Standards and Test**Procedu~es.** 

### The standards and test procedures for approval of systems designed to convert 1993 and earlier model year motor vehicles to use alcohol or alcohol/gasoline fuels in lieu of the original certification fuel system are contained in "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to.Use Alcohol or Alcohol/Gasoline Fuels,"**adopt~d** 

### by the State Board April 28, 1983, as amended March 11, 1993. The standards and test procedures for approval of systems designed to convert 1994 and subsequent model year motor vehicles to use alcohol or alcohol/gasoline fuels are contained in "California Certification and Installation Procedures for Alternative Fuel Retrofit Systems for Motor Vehicles Certified for 1994 and Subsequent Model Years," adopted by the_State Board March 11, 1993, as amended At the option of the retrofit system manufacturer, the standards and test procedures for approval of systems designed to convert 1994 and subsequent model year motor vehicles to use alcohol or alcohol/gasoline fuels may be used for approval of systems**~esigned** 

### to convert 1993 and earlier model year motor vehicles to use alcohol or alcohol/gasoline fuels in lieu of the "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor.Yehicles Certified for 1993 and Earlier Model Years to Use Alcohol or Alcohol/Gasoline Fuels."

### {b) Implementation Phase-In Schedule.**Not~ithstanding** 

### subsection (a), a retrofft system manufacturer may apply "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 

### and Earlier Model Years to Use Alcohol or Alcohol/Gasoline Fuels" to certify retrofit systems for 1994 

### and 1995 

### model-year vehicles in accordance**~ith** 

### the**follo~ing** 

### implementation phase-in schedule. Each manufacturer may certify
a maximum of 85 

### percent of its total 1994 

### model-year engine family retrofit systems and 45 

### percent of its total 1995 

### model-year systems according to the requirements of these test procedures and the "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 

### and Earlier Model Years to Use Liquefied Petroleum Gas or Natural Gas Fuels," adopted by the State Board on April 16, 19i5, 

### as amended March 11, 1993. 

### The remaining percentage of each manufacturer's certified 1994 

### and 1995 

### model-year engine family retrofit systems and all of 1996 

### and subsequent model-year engine family retrofit systems shall be certified according to "California Certification and Installation Pracedures for Alternative Fuel Retrofit Systems For Motor ' 

### Vehicles Certified For 1994 

### and Subsequent Model Years." The percentages shall be determined from the total number of retrofit systems certified and shall be met prior to the end of'the applicable calendar year. "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 

### and Earlier Model Years to Use Alcohol or Alcohol/Gasoline Fuels" 'shall not be applied to certify .a retrofit system for installation on a transitional**lo~-emission** 

### vehicle ("TLEV•),**lo~-emission** 

### vehicle ("LEV"), or**ultra-lo~-emission** 

### vehicle ("ULEV") or to certify a retrofit system designed to convert a vehicle to TLEV, LEV, or ULEV emission standards (as defined in Section 1960.1, 

### Title 13, 

### California .code of**Regulati~ns).** ' 

### NOTE: Authority cited: Sections 39515, 39600, 39601 

### and 43006, 

### Health and Safety Code; Sections 27156 

### and 38395, 

### Vehicle Code. Reference: Sections 43000, 43004, 43006, 43008.6, 43013 

### and 43018, 

### Health and Safety Code; Sections 27156, 38391 

### and 38395, 

### Vehicle Code.

# . '



### State of California AIR RESOURCES BOARD

• 

### CALIFORNIA CERTIFICATION AND INSTALLATION PROCEDURES FOR ALTERNATIVE FUEL RETROFIT SYSTEMS

FOR MOTOR VEHICLES CERTIFIED FOR 1994 AND SUBSEQUENT MODEL YEARS

Note: Proposed changes to the text adopted are indicated by 

### strike-. out (deletion) and underline (addition).

Adopted: March 11, 1993 Amended:

### 1.


### 2. 

## 3. TABLE OF CONTENTS

APPLICABILITY
DEFINITIONS

. GENERAL REQUIREMENTS (a) Product Specifications (b) Emission Control Labels (c) Owner's Manuals 

## ...

(d) Manufacturer Recordkeeping Requirement (e) Installer Recordkeeping Requirement
4. REQUEST FOR CERTIFICATION
5. TEST PROCEDURES

. (a) Description of Vehicle Categories

· (b) Test Procedures for Vehicles in Category I

(c) Test Procedures for Vehicles in Category II (d) Test Procedures for Vehicles in Category III
6. APPROVAL

. . . . (a) Issuance of Executive Orders (b) Carry-Over and Carry-Across
7. INSTALLATION REQUIREMENTS

.... Page

1
2


### 2
2

3

4

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### 5

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### 8

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### 11

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### 11 

### 8. IN-USE ENFORCEMENT TEST REQUIREMENTS

............. 12
9.**~ARRANTY** 

### REQUIREMENTS

. . . . . . 14 (a) Requirements of Manufacturers (b) Extended Warranty Requirements. (c) Requirements of Installers•..

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### 14
14

15

### California Certification and Installation Procedures for Alternative Fuel Retrofit .Systems for Motor Vehicles Certified for 1994 and Subsequent Model Years

1. · APPLICABILI.TY**(~}** 

### "Certification and Installation Procedures for Alternative Fuel Retrofit Systems for Motor Vehicles Certified for 1994 and Subsequent Model Years" ("these Procedures") apply to alternative fuel retrofit systems designed for installation on gasoline- or diesel-fueled light-, medium-, and heavy-duty motor vehicles for 1994 and subsequent model years. Only these Procedures shall be used to certify a retrofit system for installation on a . transitional low-emission vehicle ("TLEV"), low-emission vehicle ("LEV"}, or ultra-low-emission vehicle ("ULEV") or to certify a retrofit system designed to convert a vehicle•to TLEV, LEV, or ULEV emission standards {as defined in Section 1960.1, Title 13, CCR). Each manufacturer shall certify a minimum of 15 percent of 1994, 55 percent of 1995, and 100 percent of 1996 and subsequent model year engine family retrofit systems according to the requirements of these Procedures. "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use Liquefied Petroleum Gas or Nitural Gas Fuels," (for certifying liquefied petroleum gas or natural**g~s** 

### retrofit systems) and "California Exhaust Emission Standards and Test Procedures for Systems Designed to Convert Motor Vehicles Certified for 1993 and Earlier Model Years to Use Alcohol or Alcohol/Gasoline Fuels" (for certifying alcohol and a 1 cohol/gasoline retrofit systems) sha11 be used to certify the remaining percentage of 1994 and 1995 model year engine family systems and 1993 and prior model year engine family systems, except as provided in paragraph 1.(b). (b} Aretrofit system manufacturer may as an option use these Procedures to·certify alternative fuel retrofit systems des1gned for installation on pre-1994 model year gasoline- or diesel-fueled light-, medium-, and heavy-duty motor vehicles, with the following addition: the Executive Officer may order 25,000 mile**du~ability** 

### vehicle testing for alternative fuel retrofit systems designed for installation on pre-1994 model year vehicles which include hardware or components other than the fue1 conversion· system as part of the overall retrofit system. (c) Acertification issued pursuant to these Procedures shall have the effect of a certification of an alternative fuel retrofit system pursuant to Health and Safety Code Section 43006; and shall also have the effect of an exemption issued pursuant to Vehicle Code Sections 27156 and 38395.

2. DEFINITIONS

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### "Alternative fuel" refers**t~** 

### liquefied petroleum gas, natural gas, alcohol and alcohol/gasoline fuels. 1 \



### An "alternative fuel retrofit system" or "retrofit system" is a package of fuel, ignition, emission control, and engine components that are modified, removed, or added during the process of modifying a motor vehicle to operate on an alternative**fue~.** 

### "Driveability" of avehicle refers to the smooth delivery of power, as demanded by the driver. Typical causes of driveability degradation are rough idling, misfiring, surging, hesitation, or insufficient power. Conversion from gasoline to gaseous fuels usually entails a loss of volumetric efficiency, resulting in some power loss. Normal power loss shall not be considered to be driveability degradation.
"Installer" refers to a person who installs alternative fuel retrofit systems on motor vehicles.
"Retrofit system manufacturer" or "manufacturer" 'refers to a person who manufactures or assembles an alternative fuel retrofit system for sale in California and requests or is granted the Executive Order certifying the alternative fuel retrofit system.
For purposes of these Procedures "useful life" is the duration, expressed in miles, of the longest durability period for the new vehicle or**engi~e-emission** 

### standards to which the vehicle or engine was ·certified. {This is typically 50,000 miles for light-duty vehicles. However, as of the 1993**~odel** 

### year, a**pha~e-in** 

### of new, more stringent, light-duty standards with 100,000 mile useful life requirements will begin.}

3. GENERAL REQUIREMENTS (a) Product Specifications:
In addition to all other standards or requirements imposed, the following general requirements shall apply to all alternative fuel retrofit systems to be certified for installation on Californiacertified gasoline or diesel-fueled motor vehicles: (i} Alternative fuel retrofit systems for gaseous fuels shall be equipped with a lockoff valve, actuated by an electrical or vacuum signal, preventing delivery of fuel to the carburetor, or fuel injection system, while the engine is shut down. (ii) The driveability of a vehicle equipped with a retrofit system shall not be degraded in such a way as to encourage consumer tampering. To verify that the driveability of a retrofitted vehicle is acceptable, the Executive Officer may require that an independent laboratory evaluate driveability. The Executive Officer's determination that driveability must be evaluated shall be based on an engineering evaluation of the retrofit system described in the applicatiqn for certification or on reports or observations that retrofit systems similar in design

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### to the system for which certification is sought have caused driveabilty degradation. The cost of this evaluation shall be borne by the applicant. (iii) If the vehicle to be retrofitted was certified with an on-board diagnostic (080) system pursuant to Section 1968 or 1968.1, Title 13, 

### Californi.a Code of Regulations (CCR), the proper function of the on-board diagnostic system sha11 not ·be impaired as a result of the installation and operation of the alternative fuel retrofit system. This requirement may necessitate modification of the 080 system to prevent it from storing erroneous trouble codes (e.g., storing a code signifying faulty operation of the evaporative canister purge valve because the evaporative emission control system has been removed). All modifications to 080 components, programming or wiring, must be fully specified as parts of the retrofit system. If the retrofit system includes modifications to the 080 system, the applicant must submit an analysis showing that these modifications will not adversely affect 080 performance. Notwithstanding, for 1998 and previous model year vehicles, retrofit system manufacturers may request Executive Officer approval to disable specific on-board diagnostic monitoring strategies for which monitorino may not be reliable with respect to the use of alternative fuels (e.g

.. oxygen**sen~or** 

### response rate checks). The manufacturer shall submit data and/or an engineering evaluation to justify the request. (iv) With the exception of idle speed control and throttle position control, no component or calibration of the fuel system that could affect emission performance shall be adjustable by the system installer or the vehicle's user. (b) Emission Control Labels:
"California Motor Vehicle Emission Control**Labe~** 

### Specifications," incorporated by reference in Title 13, 

### CCR, Section 1965, shall apply to installations of alternative fuel retrofit systems, with the following additions: ( i )

( i i ) 

### The retrofit system manufacturer shall provide a supplemental Emission Control Information label, which shall be affixed in a permanent manner to each retrofitted vehicle, in a location adjacent to the original Emission Control Information Label. If the supplemental label cannot be placed adjacent to the original label, it shall be placed in a location where it can be seen by a person viewing the original label.
The supplemental label shall clearly state that the vehicle has been equipped with an alternative fuel retrofit system designed to allow it to operate on a fuel other than gasoline or diesel, and shall identify the fuel(s) which the vehicle is'designed to use. The label shall**sh~w** 

### the vehicle model year; the Executive Order number certifying the retrofit system; the retrofit system manufacturer's name, address, and telephone number; and shall state that the retrofitted vehic1e complies with California ·

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### emission requirements. If the retrofit system has been certified as being capable of converting the vehicle into a TLEV, LEV, or ULEV, the label shall prominently display the title, "Transitional Low-Emission Vehicle," "Low-Emission Vehicle,·" or "Ultra-Low-Emission Vehicle," as appropriate. The label shall also list any original parts ·that were removed during installation of the retrofit system, as well as any changes in tune-up specifications required for the retrofit system. In addition, the label shall show the installer's name, address, and telephone number; the date on which the retrofit system was installed; and the mileage (retrofitted vehicle odometer reading) and date at which the retrofit system warranty**~xpires.** 

### It is not necessary fQr emission control labels installed with retrofit systems to be machine readable. (iii) The retrofit system manufacturer shall provide routing diagram for each retrofit system sold. routing diagram shall be placed underhood .in a at a visible and accessible location and shall modifications to the original vacuum system. (c) Owner's Manuals: a vacuum hose The vacuum hose permanent manner show

Each retrofit system installed shall include an owner's manual containing at least the following information: (i) a brief description of the retrofit system, including major components and their theory of**ope~ation;** 

### (ii) the correct refueling procedure; I

. . 

### (iii) ·a··listing of necessary service and service intervals, as well as tune-up data, which differ from the service requirements specified by the vehicle's or engine's original manufacturer; (iv) the name, address, and phone number of the installer, as well as a list of the names, addresses, and phone numbers of the major dealers in California who supply parts for, or service, the retrofit system; and (v) warranty information. (d) Manufacturer Recordkeeping Requirement:
Manufacturers of retrofit systems shall maintain a record of the vehicle identification numbers and California license plate numbers of those vehicles on which their product has been installed. As part of this record,.manufacturers shall identify the installation date and the certification number of those systems installed on each vehicle and shall identify the vehicles' owners at the time o.f installation, including the•owners' current addresses and phone numbers at the time of installation. The retrofit system manufacturer shall supply a copy of all installation information to the Executive Officer upon request.

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### (e) Installer Recordkeeping Requirement:
Installers of retrofit systems shall maintain a record as specified in paragraph 3(d) and shall provide this information to retrofit system manufacturers upon request.

4. REQUEST FOR CERTIFICATION (a) Arequest for certification of an alternative fuel retrofit system may be submitted by an authorized representative of the retrofit**~ystem** 

### manufacturer intending to offer the retrofit system for sale or installation in the State of California. (b) Aseparate request shall be required for 

### each model year, even though the emission standards for certifying new vehicles may be the same for consecutive model years. The request shall include all test data and other information required pursuant to these Procedures, except where other provisions of these Procedures allow carry-over or carry-across of test data from an engine family to the engine family(ies) 'for which certification is sought. Procedures governing carry-over and carry-across are discussed under paragraph 6, "Approval." (c) The request for certification shall be submitted in writing, signed ·by an authorized representative of the retrofit system

manufacturer, and shall include the following: (i) Identification and description of the engine families for which the retrofit system to be certified is designed; the emission standards applicable to those engine families; and if applicable, a statement that the retrofit system is designed [A] to convert conventional vehicles into either TLEVs, LEVs or ULEVs, [8] to convert a TLEV into either an LEV or ULEV, or [C] to convert an LEV into a ULEV. (ii).A complete description of the alternative fuel retrofit system, including details of the carburetor, mixer, regulator, vaporizer, or fuel injection system; the feedback mixture control system (if applicable), part number(s), calibration data, hose routing, specifications for the fuel tank, and pressure regulator; a sample of the emission control label as specified in 3.(b); a sample of the warranty statement as specifiecl in 9(a) and (b); and all necessary modifications to the engine, emission control system, or other parts of the vehicle. (iii) Procedures for installing and maintaining the retrofit system, including tune-up specifications and discussion of any special tools or techniques required for proper installation, maintenance, or operation.

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### ( iv) '



## .
t**~** I •



### An agreement to supply the Air Resources Board, within 45 calendar days of the Executive Officer's request, with any one or more of the vehiclei used for certification testing, or to provide Air Resources Board personnel with the equipment to inspect and test such vehicles at the applicant's facility, if requested by the Executive Officer.

5. TEST PROCEDURES (a) Description**~f** 

### Vehicle**C~tegories:** 

### For the purposes of these certification Procedures, the motor vehicle fleet is divided into three major categories:
I. Passenger cars, light-duty trucks, and medium-duty vehicles as defihed in "California Exhaust Emission Standards and Test Procedures for 1988 and**S~bsequent** 

### Model Passenger Cars, Light- Duty Trucks, and Medium-Duty Vehicles"**(~s** 

### incorporated by reference.in Section 1960.1, T.itle 13, CCR), which were certified to an exhaust emission standard based on a chassisdynamometer test procedure;
II. Vehicles with gross vehicle weight ratings less than or equal to 14,000 lbs and not originally certified to a chassis dynamometer-based exhaust emission standard; and
III. Vehicles with gross vehicle weight ratings greater than 14,000 lbs. (b) Test Procedures: for Vehi c 1es in Category I:
For vehicles in Category I, the emission standards and test procedures set forth in the "California Exhaust Emission Standards and Test Procedures for 1988 and Subsequent Model Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles" also apply to the certification of alternative fuel retrofit systems, with the following exceptions: (i) The applicable emission standards shall be at least as stringent as the emission standards applicable to the engine families for which the retrofit systems to be certified are designed. In addition, vehicles retrofitted to operate on a give.n alternative fu"el shall also be subject to any additional emission standards applicable to new motor vehicles that are designed to operate on the alternative fuel, and that. are of the model year and vehicle class for which certification is sought. Amaximum of one**emission-dat~** 

### vehicle per engine family for which certification is sought shall be required. Where durability testing is required, a bench-test vehicle may be substituted for,a durability vehicle and may also be considered an emission-data vehicle. Prior to the commencement of testing, the choice of durability vehicle or bench-test vehicle, emission-data vehicle(s) and engine(s) must be

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I I 

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approved by the Executive Officer as being representative of the range of engine families for which certification is sought. (ii) For the purpose of applying the provisions of the "California Exhaust Emission Standards and Test Procedures for 1988 and Subsequent Model Passenger Cars, Light-Duty Trucks, and MediumDuty Vehicles" to certification testing of alternative fuel retrofit systems, test vehicles equipped with an alternative fuel retrofit system shall be assumed to have zero miles of mileage accumulation at the time that the retrofit system is installed. Mileage may be subsequently accumulated by driving the vehicle on the road, following a typical suburban route, or on a chassis dynamometer using the Automobile Manufacturer's Association mileage accumulation cycle (40 C.F.R., Part 86, Appendix IV, as adopted January 28, 1977). (iii) Vehicle mileage accumulation on a durability vehicle or bench aging of retrofit system components shall be conducted to determine deterioration factors. Prior to the commencement of any emission or bench aging, the applicant's test plan must be approved by the Executive Officer. Approval of the test plan shall be contingent upon a demonstration by th€ applicant that bench aging produces· deterioration factors at 1 east as great as durability vehicle testing. (iv) Bench aging conducted in lieu of vehicle mileage accumulation shall be conducted for a period of time such that the resulting deterioration 

### bfthe retrofit system**i~** 

### equivalent to that which would occur during durability vehicle mileage accumulation over a mileage equal to the useful life of the vehicle. : ! 

### (v) Vehicle mileage accumulation on a durability vehicle shall be performed in conjunction with emission testing. Before beginning vehicle mileage accumulation of the retrofit system, the system shall be installed on the durability vehicle, the vehicle shall be driven 4,000 + 

### 100 miles and the vehicle shall be tested using the alternative fuel. Adual-fuel retrofit system shall be emission tested using each fuel that it is capable of operating on. At the conclusion of vehicle mileage accumulation, a second emission test or series of tests shall be performed. Alternatively, if bench aging is used to determine deterioration factors, then bench aging shall b.e performed in conjunction with emission testing of a bench-test vehicle. Before beginning bench aging of the retrofit system, it shall be installed on the bench-test vehicle, the vehicle shall be driven for 4,000 + 

### 100 miles, and the vehicle· shall then be emission tested using the alternative fuel. Adual-fuel retrofit system shall be emission tested using each fuel that it is capable of operating on. After the emission tests are completed, the retrofit system shall be removed from the vehicle and subjected to bench aging. At the conclusion of bench aging, the retrofit**syste~** 

### shall be reinstalled on the

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### (vi)

·(vii)

(v.iii) bench-test vehicle, and a second emission test or series of tests shall be performed.
For exhaust emissions of each regulated pollutant measured during the**~ehicle** 

### mileage**accumulati~n** 

### or bench-test procedure, a deterioration factor shall be calculated by dividing the emission rate obtained during the second emission test by that obtained during the first. Jf the resulting quotient ts less than one, the deterioration factor shall be assigned ' value**~f** 

### one. The deterioration constant for ·evaporative emissions shall be calculated by subtracting the evaporative emissions found during the first emission test from those found during the second test. If the resulting difference is less than zero, the deterioration constant shall be assigned a value of zero. Choices of vehicle models, engines, and transmissions for use in emission-data vehicles shall be approved by the Executive Officer as being representative of the engine families for which certification is sought, prior to the commencement of testing. Following installation of the retrofit system, the emission-data vehicle shall be driven 4,000 + 

### 100 miles to stabilize emission rates. After the specified mileage has been accumulated, the emission-data vehicles' exhaust and· evaporative emissions, where applicable, shall be tested,**~sing** 

### the appropriate procedure as set forth in "California Exhaust Emission Standards and Test Procedures for 1988 and Subsequent Model Passenger Cars, light-Duty Trucks, and Medium-Duty Vehicles." Dual**f~el** 

### vehicles shall**b~** 

### emission tested using· each fuel that the vehicle is capable of operating on. I 

### The deteriorated emissions of emission-data vehicles shall be calculated using the deterioration factors and constants found during vehicle mileage accumulation or bench testing. The useful life exhaust emission values are defined as the product of each emission value at 4,000 miles times the corresponding deterioration factor. For evaporative emissions, the certification emission value is equal to the sum of the emissions measured at, or extrapolated to 4,000 miles, plus the deterioration constant. The durability vehicle, bench-test vehicle, and all emission-data vehicles shall meet the applicable new vehicle useful life emission standards, as well as all applicable emission standards for intermediate mileage levels, for the vehicles' model year and fuel type(s). {c) Test**Pro~edures** 

### for Vehicles in Category II:
For durability, bench-test and emission-data vehicles in Category II, test vehicles shall have accumulated a total mileage greater than 4,000 miles and less than 10,000 miles with the O(iginal fuel system, prior to emission tEsting. If 

### the manufacturerchooses to use the option as described in l(b) for pre-1994 model year vehicles, then the 10,000 mile limit shall not be applicable. A test vehicle's engine and emission control system shall be equipped and calibrated as certified. The vehicle shall then be tested for

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### exhaust and, if applicable, evaporative emissions using the test procedures set forth in the "California Exhaust Emission Standards and Test**Proced~res** 

### for 1988 and Subsequent Model Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles". The inertia weight setting shall be**eq~al** 

### to the average of the vehicle's curb weight and _gross vehicle weight rating and road load horsepower based on the frontal area of the vehicle without modifications, as determined in "California Exhaust Emission Standards and Test Procedures for 1988 and Subsequent Model Passenger Cars, Light-Duty Trucks, and Medium-Duty Vehicles," Section 9.b. The test results shall be defined as the baseline emission rates. After the baseline emission rates have been measured, the retrofit system shall be installed. (i) The procedure outlined in paragraphs S(b)(iii) through S(b)(vi) shall be used with the following modifications: ''useful life" shall equal 120,000 miles for vehicles in Category II; the durability or bench-test vehicle's emission rates of regulated pollutants measured at 4,000 ! 

### 100 miles pfter the installation of the retrofit system shall not exceed 1.10 times the baseline rates; the deteriorated exhaust emissions of regulated**pollutant~** 

### projected to 120,000 miles shall not exceed 1.3 times the baseline emissions; and the deteriorated evaporative emissions of regulated pollutants projected to 120,000 miles shall not exceed the baseline emissions plus 0.5 grams. (ii) When the Executive Officer determines that deterioration factors determined in paragraph S(c)(i) may be carried across or carried over to other engine families in Category II, the representative emission-data vehicles shall be tested as specified in paragraph S(b)(vii). Emission rates measured at 4,000 + 

### 100 miles after installation of the retrofit system shall not exceed 1.10 times the vehicles' baseline rates. (d) Test Procedures for Vehicles in Category III: Applicants requesting certification for retrofit systems for use in Category III vehicles shall submit a test plan utilizing eight mode chassis dynamometer testing to verify that the retrofit system will not cause excess emissions from engine families for which certification is sought. Test vehicles shall have accumulated a total mileage greater than 4,000 miles and less than 10,000 miles with the original fuel system·prior to emission testing. If the manufacturer chooses to use the option as described in l(b) 

### for pre-1994 model year vehicles, then the 10,000 mile limit shall not be applicable. Atest vehicle's engine and emission control system shall be equipped and calibrated as certified. The vehicle shall then be tested for exhaust emissions using the eight mode chassis dynamometer.test specified in the test plan. The test result shall be defined as the baseline emission rate. After the baseline emission rate has been measured, the retrofit system shall be installed. Emission rates**~hall** 

### then be measured at 4,000 ± 

### 100 miles after installation of the retrofit system using the eight mode chassis dynamometer test specified in the test plan.

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### (i)



### ( i i)



### (iii)

( iv) \. I I 9 '



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### Subject to the Executive Officer's approval of the applicant's test plarr prior to**~ommencing** 

### testing, testing utilizing procedures other than the eight mode chassis dynamometer test shall be allowed.
Emission testing shall be conducted to determine exhaust emission rates of carbon monoxide and the sum of non-methane hydrocarbons plus nitrogen oxides. Emissions shall not exceed 1.10 times the baseline rates. The**p~ocedures** 

### outlined in paragraphs S(b)(iii) through S(b)(vi) shall be used with the following modifications: "useful life" shall equal 180,000 miles for vehicles in Category III; the durability or bench-test vehicle's emission rates of CO, and the sum of non-methane hydrocarbons plus NOx measured at 4,000 + 

### 100 miles shall not exceed 1.10 times the baseline rates; the deteriorated exhaust emissions projected to 180,000 miles shall not exceed 1.3 times the baseline emissions; and, the deteriorated evaporative emissions projected to 180,000 miles shall not exceed baseline emissions plus 0.5 grams. For the purposes of this section, the evaporative baseline emissions shall be estimated by the manufacturer based on good engineering principles and judgment. The manufacturer's test plan shall specify the evaporative baseline emissions estimate and describe**~ow** 

### this estimate was derived.
The Executive Officer may allow**carry~across** 

### of durability data from certification bench testing of retrofit systems designed ·for vehicles i_n Categor·ies I or II to Category III retrofit

system applications, if·the'Executive Officer determines that the carry-across durability data will adequately represent the durability performance of the retrofit system to be certified. (v) Applicants requesting certification for retrofit systems designed to allow Category III vehicles to operate on an alternative fuel in addition to diesel fuel shall conduct smoke opacity testing on the emission-data vehicle(s) utilizing the peak smoke opacity standards and procedures set forth in "Heavy-Duty Diesel Vehicle Smoke Opacity Test Procedure," as incorporated by reference in Title 13, CCR, Section 2182. Smoke opacity testing shall be conduc.ted using each fuel that the retrofitted vehicle is designed to operate on. The applicable peak smoke opacity standard shall be that·set for the model year for which certification is sought. (vi) The selection of duty cycle(s) and all other aspects of the test procedure shall be subject to approval by the Executive Officer, and emission testing shall commence only after the Executive Officer has approved the test plan. The Executive Order shall be issued following review of the test data and determination that they_ meet the criteria specified in the test plan

..

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### 6. APPROVAL (a) Issuance of Executive Orders: If, after reviewing the test data and other information submitted by the retrofit system manufacturer, the Executive Officer determines that the retrofit system meets the applicable emission standards or the criteria of an approved test plan, as applicable, an Executive Order shall be issued certifying the retrofit system for sale and installation on vehicles in the engine families specified in the applic9tion. The Executive Order shall specify, if applicable, that the retrofit system is certified as [A] converting a conventional motor· vehicle into a TLEV, LEV or ULEV, [B] converting a TLEV into a LEV or ULEV, or [C] converting a LEV into a ULEV. (b) Carry-Over and Carry-Across: Carry-over of emission test data from the previous model year to the following model year will be allowed, if'the Executive Officer determines that the carry-over data wi11 adequately represent the emissions performance of the retrofit system to be certified. Carry-across to similar engin·e families will also be allowed. Applications for carry-over and carry-across must be accompanied by an engineering analysis demonstrating that the emissions and durability of the retrofit system and engine family for which certification is being sought will be. adequately represented by a certified retrofit system/engine family application. Applications for carry-over and carry-across will be evaluated according to the the criteria contained in EPA Advisory Circular 17F, which is incorporated herein by reference, and paragraph 4.b.4 of the "California Exhaust Emission Standards and Test Procedures for 1988 and Subsequent Model Passenger Cars, light-Duty Trucks, and MediumDuty Vehicles." These include, but are not limited to, similarity of catalyst location and configuration, similarity of fuel metering system, similarity of emission control system logic and design, and similarity of any other features that may affect the durability of the retrofit system's emission performance. ·

7. INSTALLATION REQUIREMENTS (a) Prior to releasing a converted vehicle to the consumer, the· installer of an alternative fuel retrofit system shall submit the converted vehicle to a Bureau of Automotive Repair Referee Smog Check Station for inspection and testing. (i) The installer of an alternative fuel retrofit system shall keep a copy of the certifiGate of compliance, issued by the Bureau of Automotive Repair Referee Smog Check Station, as part of the record specified in paragraph 3(e). The certificate of compliance shall conta\n, but need not be limited to, the following: the vehicle's identification number, the vehicle's model year and make, the date of installation, and the emissions category to which the retrofitted system is certified

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### (i

..e., conventional vehicle, TLEV, LEV, or ULEV). The original certificate of compliance shall be submitted to the vehicle owner upon the vehicle's release. (ii) The installer of an alternative fuel retrofit system shall not release the converted .vehicle to the consumer without the issuance of a certificate.of compliance for the vehicle by a Bureau of Automotive Repair Referee Smog Check Station. (iii) The installer of an alternative fuel retrofit system shall also meet the requirements of paragraph 9(c).

8. IN-USE ENFORCEMENT TEST REQUIREMENTS (a) Manufacturers of alternative fuel retrofit systems shall, upon order by the Executive Officer, perform in-use enforcement emission testing of their products. The Executive Officer may order in-use enforcement emission testing of not more thag 20 percent of a manufacturer's certified retrofit systems/engine family applications per year. If 20 percent constitutes less than one of a manufacturer's certified systems, the Executive Officer may order in-use enforcement emission testing of not more than one certified system/engine family application per year. Manufacturers shall be required to perform emission testing of not less than ten vehicles per certified retrofit system/engine family application selected by the Executive Officer for.in-use enforcement emission testing. Upon order by the Executive Officer, manufacturers shall perform the applicable emission**test~·pursuant** 

### to the following: (i) No vehicle shall be accepted by the manufacturer as a representative vehicle for enforcement testing unless the following criteria are met: (1) California certified and registered. (2) Odometer indication of less than certified useful-life mileage and vehicle age within useful-life time period. (3) No indication of**abus~** 

### (e.g., racing, overloading, misfueling, or other misuse), neglect, improper maintenance or other factors that would have an effect on emission performance. · (4) No major repair to engine or major repair of vehicle resulting from collision. · (5) lead content of fuel sample from the vehicle tank meets applicable standards. · (6) No indication of any problem that might jeopardize the safety of laboratory personnel. (ii) The manufacturer shall, under ARB supervision, perform diagnosis or restorative maintenance on those vehicles selected

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.. rJ**~** r I I

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### ( i i i )

( iv)

(v)



### (vi) 

### . for in-use enforcement testing. The manufacturer or a laboratory approved by the Executive Officer shall (1) identify part numbers of all essential emission control system components; (2) 

### check air filter, all drive belts, all fluid levels, radiator cap, all vacuum hoses and electrical wiring related to emission control for integrity; check fuel metering and emission control system components for maladjustments and/or tampering, and record all discrepancies; (3) 

### check ignition system**w~th** 

### oscilloscope and replace any defective components; i.e., spark plugs, wires, etc.; (4) 

### check compression; (5) 

### check and adjust engine parameters to manufacturer's specifications; and (6) 

### perform maintenance if the vehicle is within 500 

### miles of scheduled maintenance service.
For vehicles in Category I, 

### the manufacturer or a laboratory approved by

### the Executive Officer shall perform the applicable· emission test procedures set forth in the "California Exhaust Emission Standards and Test Procedures for 1988 

### and Subsequent Model Passenger Cars, light-Duty Trucks, and Medium-Duty Vehicles." The applicable emission standards shall be the vehicle's useful life standards as well as any intermediate emission standards, as stated in the Executive Order.
For vehicles in Category II, 

### in-use enforcement exhaust and, if applicable, evaporative emissions shall be performed using the test procedures set forth in the "California Exhaust Emission Standards and Test Procedures for 1988 

### and Subsequent Model Passenger Cars, light-Duty Trucks, and Medium-Duty Vehicles". The inertia weight setting shall be.equal to the average of the vehicle's curb weight and gross vehicle weight rating and road load horsepower based on the frontal area of the vehicle without modifications, as determined- in "California Exhaust Emission Standards and Test Procedures for 1988 

### and Subsequent Model Passenger Cars, light-Duty Trucks, and Medium-Duty Vehicles," Section 9.b. For vehicles in Category III, 

### in-use enforcement exhaust emission tests shaJl be'performed in accordance with the test plan approved by the Executive Officer prior to certification testing of the engine family applications specified for in-use enforcement testing.
The applicable exhaust emissipn standards for vehicles in Categories 

## II and 

## III shall be the baseline emission rates established during certification testing of the engine family applications specified for in-use enforcement testing·times 1.3. 

### The applicable evaporative emission standards for vehicles in Categories 

## II and 

## III shall be the baseline emission rates established during certification testing of the engine family applications**sp~cified** 

### for in-use enforcement testing plus 0.5 

### grams. Manufacturers shall comP.lete in-use enforcement testing within 6 months of the issuancd of the in-use compliance testing drder and shall submit all test data to the Executive Officer within 30 calendar days following completion of testing.

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### (vii)" Following review of manufacturer in-use enforcement test data, the Executive Officer may conduct confirmatory in-use enforcement testing. (b) 

### If the results of the in-use vehicle emission tests conducted· pursuant to paragraphs 8(a)(i)**throug~** 

### 8(a)(vii) indicate that the average emissions of the test vehicles for any pollutant exceed the applicable emission standards, the entire vehicle population so**represent~d** 

### shall be deemed to exceed such standards. Upon. order by the Executive Officer, the manufacturer shall have 45 days to submit an influenced recall plan in accordance with Sections 2111 through 2121, Title 13,. CCR. If no such recall plan is submitted, the Executive Officer may order corrective action including recall of the affected vehicles in accordance with Sections 2122 through 2135, Title 13, CCR. For the purpose of these Procedures, the term "manufacturer," as referenced in Sections 2111**throug~** 

### 2135, Title 13, CCR, ·sha11 mean

..retrofit system manufacturer

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9. WARRANTY REQUIREMENTS (a) Requirements of Manufacturers:
The manufacturer of an alternative fuel retrofit system shall warrant to the person having the vehicle retrofitted and to;each subsequent purchaser of the vehicle that the alternative fuel · retrofit system is designed and manufactured to conform with the applicable requirements of these Procedures and is free from defects fn materials and workmanship which cause the alternative fuel retrofit system to fail to conform with the applicable requirements of these Procedures or cause damage to any part on the retrofitted vehicle. This warranty shall be effective for three years or 50,000 miles,**which~ver** 

### first occurs, of customer service, and shall cover the full repair or replacement costs including the costs of diagnosis, labor, and parts (including any part on the retrofitted vehicle that is damaged due to a defect in the alternative fuel retrofit system). (b) Extended Warranty Requirements:
Each manufacturer of an alternative fuel retrofit system shall identify in its application for certification the warranted parts whose individual replacement cost, at the time of certification, exceeds the cost limit defined in paragraph 9(b)(i).**Th~** 

### replacement cost shall include the cost of the diagnosis, parts, and labor. The costs shall be those of the highest cost metropolitan area of California. Each manufacturer shall warrant to the person having the vehicle retrofitted.and to each subsequent purchaser pf the vehicle that those parts identified in its application for certification as exceeding the cost limit defined in paragraph 9(b)(i) are free from defects in materials and workmanship which cause**th~** 

### alternative fuel retrofit system to fail to conform with the requirements of these Procedures or cause damage to any part on the retrofitted vehicle, for seven years or 70,000 miles, whichever first occurs.

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### (i) The cost limit shall be calculated using the following equation:
Cost limitn 

### =$300 X(CPin_2 /121.9) where: Cost limit is the cost limit for the year in which the**alternativ~** 

### fuel retrofit system is to be certified.

n is the year in which the alternative fuel retrofit system is to be certified.
CPI is the annual average consumer price index for California published by the United States Bureau of Labor Statistics. (ii) The cost limit shall be revised annually by the Executive Officer. The highest cost metropolitan area in California shall be identified by the Executive Officer. (iii) Each manufacturer shall submit to the Executive Officer the documentation ·used to identify the warranted parts required in this subsection. The documentation shall include the estimated retail parts costs, labor rates in dollars per hour, and the labor hours necessary to replace the parts. (c) Requirements of Installers:
Each installer of an alternative fuel retrofit system shall warrant to the person.having the vehicle retrofitted and to each subsequent purchaser of the vehicle that the alternative fuel retrofit system will not fail to conform with the applicable requirements of these Procedures due to incorrect installation, and that no part on the retrofitted vehicle will be damaged due to incorrect installation. Installers of alternative fuel retrofit systems shall install only those systems of a certified configuration and shall agree to indemnify the person having the vehicle retrofitted and to each subsequent purchaser of the vehicle for the cost of repair of any vehicle upon**whi~h** 

### a noncertified configuration was installed. In addition, the installer shall agree to indemnify the person having the vehicle retrofitted and to each subsequent purchaser of the vehicle for any tampering fines that may 

### be imposed as a result of improper installation of the alternative fuel retrofit system. The warranties and agreements to indemnify shall be effective for three years or 50,000 miles, whichever first occurs, of customer service, and shall cover the full repair or replacement costs including the costs of diagnosis, labor, and parts (including.any part on the retrofitted**vehic~e** 

### that is damaged due to incorrect installation of the**~lternative** 

### fuel retrofit system).

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Before an inst•aller installs an alternative fuel retrofit system, he or she shall have submitted to the ARB a sample of the warranty statement to be provided by the installer in accordance with this paragraph.

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