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FINAL REGULATION ORDER

Amend section 1968.5, title 13, California Code of Regulations, to read as follows:

Note: Amendments are shown in double underline to indicate additions and double 

strikeout to indicate deletions from the existing regulatory text. Various portions of the 

regulations that are not modified by the proposed amendments are omitted from the text 

shown and indicated by “ * * * * ”.

§ 1968.5. Enforcement of Malfunction and Diagnostic System Requirements for 

2004 and Subsequent Model-Year Passenger Cars, Light-Duty Trucks, and 

Medium-Duty Vehicles and Engines.

(a) General

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(3) Definitions.

The definitions applicable to these rules include those set forth in Health and 

Safety Code section 39010 et seq. and in title 13, CCR sections 1900(b) and 

1968.2(c), which are incorporated by reference herein. The following definitions 

are specifically applicable to section 1968.5 and take precedence over any 

contrary definitions.

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“Nonconforming OBD II System” means an OBD II system on a production 

vehicle that has been determined not to comply with the emission standards as 

defined in requirements of title 13, CCR section 1968.2(c),. For purposes of 

section 1968.5, a motor vehicle class shall be considered nonconforming

irrespective of whether vehicles in the motor vehicle class, on average, meet 

other applicable tailpipe or evaporative emission standards (e.g., exhaust 

emission standards defined in title 13, CCR section 1960.1, evaporative emission 

standards defined in title 13, CCR section 1976).

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(b) Testing Procedures

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(3) Vehicle Selection for Enforcement Testing.

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(D)Vehicles to be included in a Test Sample Group.

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(ii) In selecting vehicles to be included in a test sample group for enforcement 

OBD II ratio testing, the Executive Officer shall include only vehicles that:

a. Are certified to the requirements of title 13, CCR section 1968.2.

b. Have collected sufficient vehicle operation data for the monitor to be 

tested. For monitors required to meet the in-use monitor performance 

ratio and to track and report ratio data pursuant to title 13, CCR section 

1968.2(d)(3.2), sufficient vehicle operation data shall mean the 

denominator meets the criteria set forth in sections (b)(3)(D)(ii)1. 
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through 3. below. For monitors required to meet the in-use monitor 

performance ratio but not required to track and report ratio data 

pursuant to title 13, CCR section 1968.2(d)(3.2), sufficient vehicle 

operation data shall mean that vehicles that have a denominator that 

meets the criteria set forth in sections (b)(3)(D)(ii)1. through 3. below 

after undergoing testing as set forth in section (b)(4)(C)(ii) below. 

Specifically, the denominator, as defined in title 13, CCR section 

1968.2(d)(4.3), for the monitor to be tested must have a value equal to 

or greater than:

1. 150 for evaporative system monitors, secondary air system 

monitors, and monitors utilizing a denominator incremented in 

accordance with title 13, CCR sections 1968.2(d)(4.3.2)(E) or (F) 

(e.g., cold start monitors, air conditioning system monitors, etc.) 

and not covered in section (b)(3)(D)(ii)2. below, or

2. 50 for PM filter monitors, and NMHC converting oxidation catalyst 

monitors, PM sensor monitors, and PM sensor heater monitors

utilizing a denominator incremented in accordance with title 13, 

CCR section 1968.2(d)(4.3.2)(F), (G), (H), or (I), or

3. 300 for catalyst, oxygen sensor, EGR, VVT, and all other component 

monitors not covered in sections (b)(3)(D)(ii)1. and 2. above.

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(6) Finding of Nonconformance after Enforcement Testing.

After conducting enforcement testing pursuant to section (b)(4) above, the 

Executive Officer shall make a finding of nonconformance of the OBD II system 

in the identified motor vehicle class if:

(A) OBD II Emission Testing.

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(ii) Intermediate In-Use Diesel Thresholds. 

a. For 2007 through 2012 model year vehicles subject to 

diesel/compression-ignition monitoring requirements in title 13, CCR 

section 1968.2(f) , the results of the OBD II emission tests indicate that 

50 percent or more of the vehicles in the test sample do not properly 

illuminate the MIL when emissions exceed:

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d. For 2013 through 2015 model year medium-duty vehicles, with respect 

to the NOx malfunction criteria for the NOx converting catalyst 

conversion efficiency monitor (title 13, CCR section 1968.2(f)(2.2.2)), 

reductant delivery performance monitor (title 13, CCR section 

1968.2(f)(2.2.3)(A)), and NOx sensor monitor (title 13, CCR section 

1968.2(f)(5.2.2)(A)), the Executive Officer shall make a finding of 

nonconformance of the OBD II system if the results of the OBD II 

emission tests indicate that 50 percent or more of the vehicles in the 

test sample do not properly illuminate the MIL when emissions exceed 

an additional 0.2 g/bhp-hr above the NOx malfunction criteria defined 
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in title 13, CCR section 1968.2(f)(2.2.2)(A)(ii)c. or 

1968.2(f)(5.2.2)(A)(ii)c.

e. For 2013 through 2015 model year medium-duty vehicles, for the PM 

filter filtering performance monitor (title 13, CCR section 

1968.2(f)(9.2.1)), the Executive Officer shall make a finding of 

nonconformance of the OBD II system if the results of the OBD II 

emission tests indicate that 50 percent or more of the vehicles in the 

test sample do not properly illuminate the MIL when emissions exceed 

0.05 g/bhp-hr.

(iii) Final In-Use Thresholds. For 2009 and subsequent model year vehicles 

subject to the gasoline/spark-ignited requirements of title 13, CCR section 

1968.2(e) and, except as provided in sections (b)(6)(A)(ii)d. and e. above, 

for 2013 and subsequent model year vehicles subject to the 

diesel/compression-ignition requirements of title 13, CCR section 

1968.2(f), the results of the OBD II emission tests indicate that 50 percent 

or more of the vehicles in the test sample do not properly illuminate the 

MIL when the emission malfunction criteria defined in title 13, CCR 

sections 1968.2(e) or (f) are exceeded.

(B) OBD II Ratio Testing.

(i) For monitors specified in sections (b)(6)(B)(i)a. through e. below, the data 

collected from the vehicles in the test sample indicate either that the 

average in-use monitor performance ratio for one or more of the monitors 

in the test sample group is less than 0.100 or that 66.0 percent or more of 

the vehicles in the test sample group have an in-use monitor performance 

ratio of less than 0.100 for the same monitor:

a. monitors on 2004 through 2016 2018 model year vehicles certified to a 

ratio of 0.100 in accordance with title 13, CCR section 

1968.2(d)(3.2.1)(D),

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(c) Remedial Action

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(3) Ordered Remedial Action-Mandatory Recall.

(A) Except as provided in sections (c)(3)(B) below, the Executive Officer shall 

order the recall and repair of all vehicles in a motor vehicle class that have 

been determined to be equipped with a nonconforming OBD II system if 

enforcement testing conducted pursuant to section (b) above or information 

received from the manufacturer indicates that:

(i) For monitors on 2007 and subsequent model year vehicles certified to the 

ratios in title 13, CCR sections 1968.2(d)(3.2.1)(A) through (C), the 

average in-use monitor performance ratio for one or more of the major 

monitors in the test sample group is less than or equal to 33.0 percent of 

the applicable required minimum ratio established in title 13, CCR section 

1968.2(d)(3.2.1) (e.g., if the required ratio is 0.336, less than or equal to a 

ratio of 0.111) or 66.0 percent or more of the vehicles in the test sample 

group have an in-use monitor performance ratio of less than or equal to 

33.0 percent of the applicable required minimum ratio established in title 
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13, CCR section 1968.2(d)(3.2.1) for the same major monitor. For 

monitors on 2004 through 2016 2018 model year vehicles certified to the 

0.100 ratio in title 13, CCR section 1968.2(d)(3.2.1)(D), the Executive 

Officer shall determine the remedial action for nonconformances regarding 

the in-use monitor performance ratio in accordance with section (c)(4) 

below.

(ii) When the vehicle is tested on-road and driven so as to reasonably 

encounter all monitoring conditions disclosed in the manufacturer’s 

certification application, the OBD II system is unable to detect and 

illuminate the MIL for a malfunction of a component/system monitored by 

a major monitor (other than the monitors for misfire causing catalyst 

damage and the evaporative system) prior to emissions exceeding two 

times the malfunction criteria of title 13, CCR sections 1968.2(e) and (f) 

(e.g., if the malfunction criteria is 1.75 times the applicable FTP standard, 

recall would be required when emissions exceed 3.5 times the applicable 

FTP standard or if the malfunction criteria is the PM standard plus 0.02 

g/bhp-hr and the PM standard is 0.01 g/bhp-hr, recall would be required 

when emissions exceed 0.06 g/bhp-hr). Additionally, for the first two years 

that a new major monitor is required in title 13, CCR section 1968.2(e) 

(e.g., 2006 and 2007 model year for cold start strategy monitoring in title 

13, CCR section 1968.2(e)(11)), the Executive Officer shall use three 

times the malfunction criteria in lieu of two times the malfunction criteria 

(e.g., if the malfunction criterion is 1.5 times the applicable FTP standard, 

recall would be required when emissions exceed 4.5 times the applicable 

FTP standard). Additionally, for major monitors on 2007 through 2009 

model year vehicles certified to the monitoring requirements in title 13, 

CCR section 1968.2(f) and for the PM filter filtering performance monitor 

(title 13, CCR section 1968.2(f)(9.2.1)) on 2013 model year medium-duty 

vehicles, the Executive Officer shall determine the remedial action for 

nonconformances regarding emission exceedance in accordance with 

section (c)(4) below in lieu of the criteria in section (c)(3)(ii). For purposes 

of the emission exceedance determination, carbon monoxide (CO) 

emissions are not considered. 

(iii) For misfire monitors:

a. Gasoline misfire monitor: The monitor for misfire causing catalyst 

damage is unable to properly detect and illuminate the MIL for misfire 

rates that are more than 20 percentage points greater than the misfire 

rates disclosed by the manufacturer in its certification application as 

causing catalyst damage (e.g., if the disclosed misfire rate is 12

percent, recall would be required if the misfire rate is greater than 32 

percent without proper detection).

b. Diesel misfire monitor: For 2019 and subsequent model year mediumduty diesel vehicles, the misfire monitor is unable to properly detect 

and illuminate the MIL for misfire rates that are more than 10 

percentage points greater than the misfire malfunction criteria specified 
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in title 13, CCR section 1968.2(f)(3.2.2) (e.g., misfire rate more than 15 

percent if the misfire malfunction criteria is 5 percent).

(iv)When the vehicle is tested on-road and driven so as to reasonably 

encounter all monitoring conditions disclosed in the manufacturer’s 

certification application, the evaporative system monitor is unable to detect 

and illuminate the MIL for a cumulative leak or leaks in the evaporative 

system equivalent to that caused by an orifice with a diameter of at least 

1.5 times the diameter of the required orifice in title 13, CCR section 

1968.2(e)(4.2.2)(C).

(v) When the vehicle is tested on-road and driven so as to reasonably 

encounter all monitoring conditions disclosed in the manufacturer’s 

certification application, the OBD II system cannot detect and illuminate 

the MIL for a malfunction of a component that effectively disables a major 

monitor and the major monitor, by being disabled, meets the criteria for 

recall identified in sections (c)(3)(A)(ii) or (iv) above (e.g. is unable to 

detect and illuminate the MIL for malfunctions that cause FTP emissions 

to exceed two times the malfunction criteria).

(vi) For 2013 and subsequent model year medium-duty diesel vehicles, when 

the vehicle is tested on-road and driven so as to reasonably encounter all 

monitoring conditions disclosed in the manufacturer’s certification 

application, the PM filter monitor is unable to detect and illuminate the MIL 

for any of the following: 

a. a missing substrate fault in accordance with title 13, CCR section 

1968.2(f)(9.2.5); or 

b. a malfunction of the PM filter that causes PM emissions to be equal to 

or greater than the emission level of the engine or vehicle, as 

measured from an applicable emission test cycle (i.e., FTP or SET), 

with the PM filter substrate completely removed. 

(vi)(vii) The motor vehicle class cannot be tested so as to obtain valid test 

results in accordance with the criteria identified in section (b)(6)(C)(ii) due 

to the nonconforming OBD II system.

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NOTE: Authority cited: Sections 39010, 39600, 39601, 43000.5, 43013, 43016, 43018, 43100, 43101,

43104, 43105, 43105.5, 43106, 43154, 43211 and 43212, Health and Safety Code. Reference:

Sections 39002, 39003, 39010, 39018, 39021.5, 39024, 39024.5, 39027, 39027.3, 39028, 39029,

39031, 39032, 39032.5, 39033, 39035, 39037.05, 39037.5, 39038, 39039, 39040, 39042,

39042.5, 39046, 39047, 39053, 39054, 39058, 39059, 39060, 39515, 39600-39601, 43000,

43000.5, 43004, 43006, 43013, 43016, 43018, 43100, 43101, 43102, 43104, 43105, 43105.5,

43106, 43150, 43151, 43152, 43153, 43154, 43155, 43156, 43204, 43211 and 43212, Health

and Safety Code.