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SURFACE «"AI!! ...... J2848-2 JUN201 1 

Sl'.E lnternationaF VEHICLE - RECOMMENDED Issued 2011-06 

PRACTICE 

Tire Pressure Systems- M aintenance {A T IS) Type 

For Medium and Heavy Duty Highway Vehicles 

RATIONALE 

Today the world of mobility is served extensively by tires which are pneumatic in design. To function correctly these tire 

designs need pneumatic pressure to derive their performance characteristics - optimum tread wear. fuel economy, ride 

quality, or fatigue life - hence the value of keeping the retained pressure at design levels ranks high. 

While periodic inspection and the periodic action of adjusting the inflation pressure while a vehicle is at rest has been the 

norm for maintaining pressure, the need to hold tire inflation pressures closer to their design targets over time, even while 

operating a vehicle on the open road at highway speeds, becomes apparent The minimum performance capabilities 

recommended in the following document support these needs. 

Within the medium and heavy-duty vehicle industry, the equipment supplier community has responded to the need to 

maintain inflation pressure, by developing various tire pressure systems which automatically re-inflate the tire/wheel 

assemblies even while operating on the highway. Because these systems do not require any intervention or action by the 

operator, operators will eventually come to rely upon these systems to maintain tire inflation pressure. It is therefore 

important that all marketed systems provide an adequate level of performance to assure continued in-service safety. 

Tires and wheels are integral components of tire pressure systems. The system attributes for tire pressure systems 

described herein assume an appropriate fitment of tire and wheel for each application, and that these tire pressure 

systems are not dependent on the performance or physical characteristics of the tire or wheel components. The 

substitution of one tire/wheel assembly for another tire/wheel assembly of another configuration, appropriate for the 

vehicle system, shall not render the tire pressure system inoperative, so long as it provides a pneumatic chamber for the 

inflation gas. 

Under SAE document J2848-1 , the system functions and performance expectations for tire pressure monitoring systems 

have been established. The subject document (SAE J2848-2) addresses tire pressure maintenance systems for which it 

is essential that the performance and communications to the driver be consistent with that established for tire pressure 

monitoring systems (see Figure 1 ). 

SAE Technical Standards Board Rules provide that: "This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is 

entirely voluntary, and its applicability and suitability for any particular use. including any patent infringement arising therefrom. Is the sole responsibility of the user.· 

SAE reviews each technical report at least every five years at which time it may be reaffirmed. revised. or cancelled. SAE invites your wntten comments and suggestions 

Copyright C 2011 SAE lntomatlonal 

All nghts reseNed No part of thos publication may be reproduced. stored on a retneval system or traru~motted , on any fonn or by any means. electronic. mechanocal. 

photocopying. reoordong, or otherwise, without the pnor wntt.en permission of SAE 

TO PLACE A OOCUMENT ORDER: Tel: 877-606-7323 (Inside USA and Canada) 

Tel: +1 724-776-4970 (outside USA) 

SAE WEB ADDRESS: 

Fax: 724-776-0790 

Email: CustomcrScrvlcc@sao.org 

http:/twww.sae.org 

SAE values your input To provide feedback 

on this Tech nical Report, please visit 

http://www.sae.org/technlcallstandards/J2848/2 201106 
SAE 

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J2848-2 Issued JUN2011 

CTIS 

~-------~(Managem nt) 

FIGURE 1- RELATIONSHIP OF TIRE PRESSURE SYSTEMS 

Page 2 of 15 

While tire pressure maintenance systems do not relieve the driver of his immediate responsibility to take the 

recommended maintenance action, these systems must still keep the driver informed of the status of the pressure level 

and make him aware when the system applied is no longer performing its intended function. 

This document incorporates the attributes of pressure maintenance systems into the management of tire inflation 

pressure while retaining the alerts and warnings so vitally important to the driver. 
SAE 

1. 

1.1 

2. 

2.1 

2.1.1 

2.1.2 

2.1.3 

2.2 

2.2.1 

2.2.2 

2.2.3 

2.2.4 

2.2.5 

2.2.6 

3. 

3.1 

3.2 

4 . 

4.1 

4.2 

4.3 

4.3.1 

4.3.2 

4.3.3 

5. 

5.1 

5.2 

5.3 

5.4 

6. 

6.1 

7. 

7.1 

FIGURE 1 

FIGURE 2 

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J2848-2 Issued JUN2011 Page 3 of 15 

TABLE OF CONTENTS 

SCOPE .......................................................................................................................................................... 4 

Purpose ......................................................................................................................................................... 4 

REFERENCES .............................................................................................................................................. 4 

Applicable Documents .................................................................................................................................. 4 

SAE Publications ........................................................................................................................................... 5 

ASTM Publication .......................................................................................................................................... 5 

Federal Publications ..................................................................................................................................... 5 

Related Publications ..................................................................................................................................... 5 

The Tire and Rim Association Publication .................................................................................................... 5 

ETRTO Publication ....................................................................................................................................... 6 

JATMA Publication ........................................................................................................................................ 6 

ISO Publications ............................................................................................................................................ 6 

ATA Publication ............................................................................................................................................. 6 

Federal Publications ..................................................................................................................................... 6 

DEFINITIONS ............................................................................................................................................... 7 

Terms ............................................................................................................................................................ 7 

Symbols and Abbreviations .......................................................................................................................... 8 

TIRE PRESSURE SYSTEMS- MAINTENANCE TYPE ............................................................................... 8 

General System Requirements ..................................................................................................................... 8 

Advanced System Requirements ................................................................................................................ 1 0 

Component Performance Requirements - Valves, Sensors, Regulators, Control Modules, etc ................ 10 

Environmental ............................................................................................................................................. 10 

Corrosion ..................................................................................................................................................... 10 

Proof Pressure ............................................................................................................................................ 11 

TIRE PRESSURE SYSTEM ....................................................................................................................... 11 

System HMI Characteristics ........................................................................................................................ 11 

System Performance Thresholds ............................................................................................................... 12 

Controls, Symbols, Switches ...................................................................................................................... 12 

Owner's Manual Information ....................................................................................................................... 12 

A TIS SYSTEM - PERFORMANCE DEMONSTRATION ............................................................................ 13 

Vehicle Test (Power Unit, Trailers, Dollies) ................................................................................................ 13 

NOTES ........................................................................................................................................................ 15 

Marginal Indica ............................................................................................................................................ 15 

RELATIONSHIP OF TIRE PRESSURE SYSTEMS ..................................................................................... 2 

MAINTENANCE SYSTEM OPERATING RANGE ...................................................................................... 12 
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SAE J2848-2 Issued JUN2011 Page 4 of 15 

1. SCOPE 

This SAE Recommended Practice defines the system and component functions, measurement metrics, and testing 

methodologies for evaluating the functionality and performance of ground vehicle tire pressure maintenance (ATIS} 

systems (systems which automatically restore the inflation pressure to its specified level), and recommended maintenance practices for these systems within the known operating environments. 

These systems are recommended to address all serviceable tires as originally installed on a vehicle by the OEM and/or 

specialty vehicle manufacturer, and for the aftermarket (including replacement or spare parts) are recommended (but optional) to address all tire/rim combinations installed after initial vehicle sale or in-use dates. 

This document is applicable to all axle and all wheel combinations for the following vehicle types - single unit powered 

vehicles exceeding 7257 kg (16 000 lb) gross vehicle weight rating (GVWR), and multi-unit vehicle combinations, up to three towed units, which use an SAE J560 connector for power and/or communication, or equivalent successor connector 

technology. For combination vehicles including two or more trailers, the dolly axles are also included. The included 

vehicles can be newly manufactured vehicles or existing vehicles, fitted with air or hydraulic braking systems. 

SPECIAL NOTE: Equipment known as 'dual tire equalizers' are commonly used with this category of vehicles. When 

employing an A TIS system, dual tire equalizers systems are not recommended as they run counter to 

the purpose of the maintenance system. 

NOTE: The following systems are not being addressed in this edition of the subject document. 

1. The management system types and more mature/complex versions of maintenance and management types, to include on-board reporting/storage/retrieval data/control capabilities, will be addressed separately by future 

changes/additions to this document series. 

2. Tire pressure monitoring systems- These systems have been addressed under SAE J2848-1. 

1.1 Purpose 

The installed systems for the maintenance of tire inflation pressure defined herein are on-board vehicle systems only. The 

maintenance type systems described herein may be controlled mechanically, electronically, and/or a combination of both, 

and should include sensing, restoring, and indicating/communicating, and recording (when specified by the OEM or user) 

capabilities. The design approach taken is expected to support the purpose and performance objectives of such a 

maintenance type system, and to function within the intended operating environment and design configuration of the vehicle itself. 

The tire pressure system of the maintenance (ATIS) type is intended to (1 ) restore the tire's lost inflation gas, measured 

as inflation pressure, relative to the SSP (specified service pressure) under each operational stage; (2) maintain the specified service pressure level for the typical range of ambient conditions; and (3) provide the driver with indications of 

low uncorrected pressure(s) and system malfunction. 

2. REFERENCES 

2.1 Applicable Documents 

The following publications form a part of this specification to the extent specified herein. Unless otherwise indicated, the 

latest issue of SAE publications shall apply. 
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SAE J2848-2 Issued JUN2011 Page 5 of 15 

2.1. 1 SAE Publications 

Available from SAE International, 400 Commonwealth Drive, Warrendale, PA 15096-0001 , Tel: 877-606-7323 (inside 

USA and Canada) or 724-776-4970 (outside USA), www.sae.org. 

SAE J560 Primary and Auxiliary Seven Conductor Electrical Connector for Truck-Trailer Jumper Cable 

SAE J1211 Handbook for Robustness Validation of Automotive Electrical/Electronic Modules 

SAE J1455 Recommended Environmental Practices for Electronic Equipment Design in Heavy-Duty Vehicle 

Applications 

SAE J1609 Air Reservoir Capacity Performance Guide- Trucks and Buses 

SAE J1939 Recommended Practice for a Serial Control and Communications Vehicle Network 

SAE J2334 Laboratory Cyclic Corrosion Test 

SAE J2402 Road Vehicles- Symbols for Controls, Indicators, and Tell-tales 

SAE J2721 Recommended Corrosion Test Methods for Commercial Vehicle Components 

SAE J2848-1 Tire Pressure Monitoring Systems - For Medium and Heavy Duty Highway Vehicles 

2.1.2 ASTM Publication 

Available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, West Conshohocken, PA 19428-2959, 

Tel: 610-832-9585, www.astm.org. 

ASTM B 117 Salt Spray (Fog) Testing 

2.1.3 Federal Publications 

Available from Federal Motor Carriers Safety Administration, United States Department of Transportation, 1200 New 

Jersey Avenue, SE, Washington , DC 20590, Tel: 1-800-832-5660, www.fmcsa.dotgov. 

Commercial Vehicle Tire Condition Sensors (FMCSA - Dec. 2003) 

Tire Pressure Monitoring and Maintenance Systems Performance Report (FMCSA - Jan. 2007) 

2.2 Related Publications 

The following publications are provided for information purposes only and are not a required as part of this SAE Technical 

Report. 

2.2.1 The Tire and Rim Association Publication 

Available from The Tire and Rim Association, 175 Montrose West Avenue, Suite 150, Copley, OH 44321 , Tel: 330-666-

8121, www.us-tra.org. 

Tire and Rim Year Book 
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SAE J2848-2 Issued JUN2011 Page 6 of 15 

2.2.2 ETRTO Publication 

Available from The European Tyre and Rim Technical Organisation, Secretariat, Av. Brugmann, 32/2, B- 1060 Brussels, 

Belgium, Tel: +32-2-344-40-59, www.etrto.org. 

ETRTO Standards Manual 

2.2.3 JATMA Publication 

Available from the Japan Automobile Tyre Manufacturers Association, 8 Floor, No. 33 Mori Bldg., 3-8-21 Toranomon, 

Minato-ku, Tokyo, 105-0001 Japan, Tel: 81-3-3435-9094, www.jatma.or.jp. 

JATMA Year Book 

2.2.4 ISO Publications 

Available from American National Standards Institute, 25 West 43rd Street. New York, NY 10036-8002, Tel: 212-642-

4900, www.ans1 org. 

ISO 7000 Graphical symbols for use on equipment-Index and synopsis 

ISO 2575 Road Vehicles-Symbols for controls, indicators and tell-tales 

ISO/IEC 2575:2004 Road vehicles. Symbols for controls, indicators and tell-tales 

2.2.5 ATA Publication 

Available from American Trucking Associations Headquarters, 950 North Glebe Road, Suite 210, Arlington, VA 22203-

4181 , Tel: 703-838-1700, www.truckline.com. 

ATAITMC RP-235A Guidelines for Tire Inflation Pressure Maintenance (2008} 

2.2.6 Federal Publications 

Available from Federal Communications Commission, 445 12th Street, SW, Washington, DC 20554, Tel: 1-888-225-5322, 

www.fcc.gov. 

47 CFR Part 15 Telecommunications - Federal Communications Commission- Radio Frequency Devices 

Available from the Federal Register, National Highway Traffic Safety Administration, 400 Seventh Street, SW, 

Washington, DC 20590, www.nhtsa.dot.gov. 

Title 49 Code of Federal Regulations Federal Motor Vehicle Safety Standards- Part 571 

FMVSS 101 

FMVSS 120 

FMVSS 105 

FMVSS 135 

FMVSS 121 

Controls and Displays 

Tire Selection and Rims - Tire selection and rims for motor vehicles with a GVWR 

of more than 4,536 kilograms (10,000 pounds). 

Hydraulic and Electric Brake Systems 

Light Vehicle Brake Systems 

Air Brake Systems 
SAE J2848-2 Issued JUN2011 Page 7 of 15 

3. DEFINITIONS 

3.1 Terms 

3.1.1 Baseline Temperature 

The temperature condition when the tire's contained air, the tire's interior structure, and the adjacent ambient air 

temperature are the same 

3. 1.2 Standard Tire Mounting 

The action of assembling a tire and its specified wheel by button-holing the tire's beads over the wheel's flanges using a 

mechanized, rotating bead bar, or manual mounting tools. 

3.1.3 Specified Service Pressure (SSP) 

The 'cold' pressure level for a tire/wheel assembly defined by the vehicle manufacturer or tire manufacturer for the 

intended service conditions (load, speed, etc.) of a given vehicle. 

3.1.4 Operational Service Pressure (OSP) 

The actual pressure level of the tire/wheel assembly at any point during service whether at ambient or at elevated 

temperature due to rolling under load. 

3.1.5 Self Diagnostic 

A device function by which an analysis of system readiness can occur resulting in a positive or negative outcome. 

3. 1.6 Tire Pressure System 

A group of interacting components whose purpose is to measure, directly or through other parameters which correlate to 

pressure, the pressure level of the tire/wheel assembly. 

3.1.7 'ATIS' 

A generic term for tire pressure systems of the maintenance type which when fitted to a vehicle (1) sense the drop in 

gauge pressure level in a tire/wheel assembly directly or indirectly, (2) provide a one-way flow of inflation gas into each 

assembly, and (3) restore the gauge pressure reading to the specified level. 

3.1.8 Low Pressure (re-inflate) Threshold 

A change of pressure (.A P) relative to the OSP indicating an actual loss of inflation gas from the tire/wheel assembly, or 

as a change in a parameter(s) which directly relate(s) to the actual loss of inflation gas, which serves as a trigger for 

activating the installed tire pressure system's response. 

3.1.9 Minimum Activation Pressure (MAP) 

A gauge pressure reading below the SSP which serves as a trigger for activating the installed tire pressure system's 

response, and defines the low pressure threshold regardless of the actual loss of inflation gas. 

3.1.1 0 Human Machine Interface (HMI) 

The device(s) which serve to bring about an understanding or communication between a human and a machine 

concerning the status of the monitored parameter(s). 
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SAE J2848-2 Issued JUN2011 Page 8 of 15 

3.1.11 Cold Tire Inflation Pressure 

Tire pressure at the prevailing ambient temperature. in the absence of any pressure build-up due to tire usage. 

3.1.12 Quasi-stationary 

Vehicle creeping forward at very low speed, causing at least one full revolution of each installed tire/wheel assembly. 

3.1.13 Gross Vehicle Weight Rating (GVWR) 

Means the value specified by the manufacturer as the loaded weight of a single motor vehicle. 

3.1.14 Gross Combination Weight Rating (GCWR) 

Means the value specified by the manufacturer as the maximum loaded weight of a combination (articulated) motor 

vehicle. 

3.1.15 Lockout 

System function whereby the re-inflate system is isolated from the brake pressure supply reservoir preventing a further 

reduction in the pressure level of this reservoir. 

3.2 Symbols and Abbreviations 

OUT - Device Under Test 

A TIS - Tire Pressure Maintenance System 

TPMS - Tire Pressure Monitoring System 

SSP - Specified Service Pressure 

OSP - Operational Service Pressure 

HMI -Human Machine Interface 

MAP - Minimum Activation Pressure 

FMVSS - Federal Motor Vehicle Safety Standards 

FMCSA - Federal Motor Carrier Safety Administration 

4. TIRE PRESSURE SYSTEMS - MAINTENANCE TYPE 

4.1 General System Requirements 

4.1.1 The A TIS system is a system mechanically or sensor activated by a demand for compressed air in one or more of 

the tire/wheel assemblies, vehicle rolling and optionally, vehicle stationary. 

4.1.2 The ATIS system should be capable of restoring the lost inflation gas (adding of compressed gas) to each 

tire/wheel assembly of the power unit, trailer, or dolly unit so equipped, without negative effects to any other airpowered systems or accessories on each vehicle so equipped. 

4.1.3 Even with a A TIS system installed, one must still be able to manually check, inflate, or deflate each tire/wheel 

assembly, and have access to the inflation valves without the use of non-traditional tools, and certainly not 

specialty tools, or adapters. 
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SAE J2848-2 Issued JUN2011 Page 9 of 15 

4.1.4 While the A TIS system may be self-responding, these systems should still have the capacity (1) to indicate to the 

operator a low pressure condition in any of the tire/wheel assemblies connected to the air system and (2) to warn 

the operator of any continuous pressure drawn-down condition but not later than the point of system isolation 

from the supply reservoir. This indicator circuit may be activated by either turning the ignition "ON" in the case of 

the power unit, or by making a power connection in the case of a trailer or dolly unit, or may use a combination of 

vehicle power and self-power. 

4.1.5 The ATIS system when installed on any one of the following vehicle types - single unit powered vehicles 

exceeding 7257 kg (16 000 lb) gross vehicle weight rating (GVWR), and/or trailers (with dolly axles as applicable) 

which use an SAE J560 connector for inter-vehicular power and/or communication, or equivalent successor intervehicular connector technology - should be capable of maintaining all axle and all wheel combinations. 

4.1.6 The A TIS system should contain one or more air check valve(s) (1) which are capable of isolating the re-inflate 

system from each rapid pressure loss assembly, and from an assembly during the action of tire/wheel changeout, (2) which are capable of isolating the air brake system reservoir (where appropriate) from the re-inflate 

system to meet the criteria of 49 CFR Part 571 .121 (FMVSS 121), 49 CFR 393 Subpart C, and 49 CFR 393.207, 

and (3) with sufficient safeguards to prevent back flow into the applicable truck or bus, prime mover (tractor), 

and/or trailer vehicle air system. 

4.1.7 The vehicle compressed air supply which is used to re-inflate the tire/wheel assembly should supply 'clean, dry' 

air to the ATIS system, and will have sufficient capability to operate the ATIS system as intended by the system 

manufacturer to support the volume demand of the fitted tire/wheel assemblies. (On legacy vehicles, a pressure 

step-up or booster unit may be required.) 

4.1.8 With regard to a system's function, the tire pressure system manufacturer should specify accuracy, nominal 

level/reading, and normal operational range for included components and make such information available for all 

users. Ultimately, the accuracy of the system components should be sufficient to keep the inflation pressure 

within the specified pressure range. 

4.1.9 The tire pressure system sampling rates and sensor capabilities should be sufficient to support the 

communication requirements at the HMI (see Section 5). 

4. 1.10 The A TIS system should be configured to add inflation gas. but, by definition, is not required to reduce the 

inflation pressure . 

4.1.11 If used, the wired or wireless communication link between a power unit and trailer(s), should perform to the 

guidelines delineated in SAE J2848-1 . 

4.1.12 If used, the link between a wireless pressure sensor and its receiving module should perform to the guidelines of 

SAE J2848-1. 

4. 1.13 The specified service pressure (SSP), or reference pressure, is determined in cooperation with the vehicle OEM 

or specialty manufacturer and the tire manufacturer, based on the vehicle capacity, the maximum applied axle or 

wheel position loads, and operating conditions. For reference purposes only, an industry accepted method for 

determining the appropriate specified service pressure has been documented in the American Trucking 

Association's TMC RP-235: Guidelines for Tire Inflation Pressure Maintenance. 

4.1.14 The A TIS system should have the capability to allow the initialization and adjustment of the system's set point for 

the SSP in the field by authorized personnel. On the other hand, should the system be disabled by error or 

through tampering, the ATIS should provide to the driver an indication that the reinflation system has been 

isolated from the supply reservoir. 

4.1.15 The ATIS system should have the flexibility of design such that the removal or replacement of a tire/wheel 

assembly can be accomplished in a safe manner and will not render the system inoperative. 
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SAE J2848-2 Issued JUN2011 Page 10 of 15 

4.1.16 For operators who use nitrogen inflation upon initially filling each tire, it is acceptable to top-off such assemblies 

using compressed air from the A TIS system should authorized personnel so desire. 

4.1.17 The typical operational conditions and configurations for which ATIS systems should function properly (during 

either the sensing or the re-inflate mode) are outlined below: 

a. Speed -The tire pressure system should function installed in a vehicle while rolling at any vehicle design speed when 

sufficient air pressure is available, and optionally, while resting stationary. 

b. Road Surfaces - The tire pressure system should function installed in vehicles operating on all improved road 

surfaces, unless specified otherwise. 

c. Maneuvers- The tire pressure system should function during all safe driving maneuvers. 

d. Loading- The tire· pressure system should function properly across the full loading range of the powered vehicle, and 

the full loading range of the trailer unit(s) per the vehicle manufacturers' recommended limits. 

e. Temperature - The tire pressure system should function when properly installed and used as intended on vehicles 

specified under 4.1.6 operating in ambient temperatures ranging from -40 °C (-40 °F) to 55 oc (131 °F), and under the 

full range of system operating temperatures when supplied with clean, dry air. 

4.2 Advanced System Requirements 

Should the installed A TIS system be a full featured electronic system (sensor within every wheel assembly initiating a reinflation action, communication on the dashboard of the ongoing status of the maintenance system, wireless 

communications, etc.), refer to SAE J2848-1 for the associated system functions, measurement metrics, and testing 

methodologies. 

4.3 Component Performance Requirements- Valves, Sensors, Regulators, Control Modules, etc. 

4.3.1 Environmental 

It is the intent that electronic device(s) and mechanical components that are mounted in/on the tire/wheel environment or 

on the vehicle should be sufficiently robust, with typical design safety factors, and 'hardened' by design, be capable of 

successfully completing all the tests - thermal cycling, thermal shock, humidity, altitude. mechanical shock, drop, 

mechanical vibration, and combinations of these conditions. 

The recommended test method for these conditions is defined in SAE J1455. The functionality of the device(s) under test 

(OUT) should be verified before and after testing. Additionally, each OUT should be visually inspected for damage before 

and after testing. Unless otherwise specified, each OUT must be at ambient atmospheric pressure, relative humidity, and 

temperature unless specified otherwise for each test. 

4.3.2 Corrosion 

The identification of potential physical contaminates, and the mitigation/elimination of their corrosive effects is critical to 

both performance and longevity of all tire pressure systems and related hardware. Depending on system type, the design 

and performance of the system components must be addressed in regards to potential system contaminants: for 

example, power connections; sensing units; component attachment points/locations; inflation supply and source, and 

check valves. 

The recommended test methodology for physical contaminates is to apply the laboratory conditions for corrosive events 

and cycles, and the chemical mixtures (solutions) as defined in SAE J2721. 
• I "\I I I II \ c 

SAE J2848-2 Issued JUN2011 Page 11 of 15 

4.3.3 Proof Pressure 

Though the service pressure for most tire pressure systems is as specified on the tire placard, there are instances when 

the device can be exposed to pressure levels above those listed. For pressure sensing devices. it is important that these 

devices continue to function even after exposure to elevated pressures, and that the device itself does not fail 

compromising the ability of the tire/wheel assembly to hold pressure. 

A recommended test method is to attach the OUT to a pressure vessel. Pressurize the vessel to not less than 150 psig 

unless superceded by a higher maximum worl<ing pressure by the vehicle OEM. Maintain the applied pressure for 30 min, 

then release to ambient atmospheric pressure. and immediately test for functionality once pressure and temperature are 

stable. 

5. TIRE PRESSURE SYSTEM 

The tire pressure system, maintenance type, should employ a design-for-use approach to make its operation selfdirected. In other words, the human-machine-interface envelope should require as little operator inputs as may be 

economically viable within state-of-the-art technology, in order to mitigate or eliminate the potential for intentional and 

unintentional errors and/or vehicle operator-induced/maintainer-induced damage. 

5.1 System HMI Characteristics 

5.1 .1 Warning Devices 

The ATIS system should be capable of communicating a warning to the driver, and continue to warn until the pressure 

has been restored, for the following conditions. 

a. a low pressure condition, namely whenever the pressure level in any tire/wheel assembly drops below the system's 

MAP, 

b. any continuous pressure drawn-down condition but not later than the point of system isolation from the supply 

reservoir, namely the minimum pressure for brake system operation. 

5.1.2 A single driver warning device is desirable, however, lacking such an arrangement, each additional unit (trailer or 

dolly) should have at least an external warning device visible to the driver. 

5.1.3 The minimum configuration of the device for communicating a warning to the driver should be a panel with optical 

telltale(s) which communicate by their operational mode(s) a low pressure condition, or the isolation of the reinflation system from the supply reservoir. Regardless of the design solution, the telltale must illuminate whenever 

the system is not at rest, i.e., flowing or attempting to flow compressed air to a tire/wheel assembly. 

5.1.4 Location 

The indicator panel should always be available for the driver's viewing. Whether available on the dashboard or other 

location within the cab, or on the exterior of the trailer, the location is optional. 

5.1.4.1 If a dashboard display option is selected, this communication must be marked appropriately for the system 

installed, and carry different action (manual} instructions than that of a tire pressure monitoring system. 

5.1.4.2 If a trailer display option is selected, this communication must be visibly available to the driver/operator for each 

trailer pulled, even if multiple trailers are involved. 
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SAE J2848-2 Issued JUN2011 Page 12 of 15 

5.2 System Performance Thresholds 

5.2.1 The response thresholds for a tire pressure system of the maintenance type are defined as follows (see also 

4.1 .13 for the SSP): 

a. The minimum activation threshold for the re-inflate function should not be less than 97% of the tire's specified service 

pressure (SSP). 

b. The optimum activation threshold for the re-inflate function is 97% of the tire's operational service pressure (OSP) in 

its operational state (OSP-3% curve). 

c. The re-inflate function should de-activate no later than the pressure level associated with the operational service 

pressure (OSP) in its operational state (OSP curve). 

Tire Pressure Maintenance System 

Sustaining the pressure within a range 

Q) 

... 

::s 

1/) 

1/) 

~ 

a. 

SSP=OSP 

----1 

I 

I 

I 

I 

I 

I 

OSP (res ponding to temperature) 

!Optimum Operating Range I 

+ OSP 

Acceptable Operating 

Pressure Range 

MAP (97% of SSP) 

f-. Time (VehiCle Rolling) 

SSP= Specified Service Pressure 

OSP = Operational Service Pressure 

OSP in its operational state (responding to temperature) 

MAP = Minimum Activation Pressure 

0 timum Activation Threshold 

FIGURE 2- MAINTENANCE SYSTEM OPERATING RANGE 

5.3 Controls, Symbols, Switches 

5.3.1 If the use of an A TIS system switch or button requires the driver to first consult his owners manual, a sticker on 

the display or a message on one of the first display screens upon activation should direct him accordingly. 

5.4 Owner's Manual Information 

5.4.1 For each system installed, it is essential that a full set of instructions and explanations be made available to the 

Operator in the Owners Manual. This information should include the type of system applied to each unit (tractor or 

power vehicle), its function , how to interpret the data panel display, and necessary system maintenance actions. 

This information should be specific to and accompany each vehicle, or trailer unit. 

5.4.2 Even with an ATIS system installed, it is incumbent upon the operator or fleet maintenance responsible to 

conduct a check of the inflation pressure of each assembly and to restore the inflation pressure to the specified 

level, prior to operating the vehicle on the highway. 
II 1 I 1 ll1 1 "\1 l1 1 I •II I \ ( o h 1 I 1 I, I IS 

SAE J2848-2 Issued JUN2011 Page 13 of 15 

6. A TIS SYSTEM - PERFORMANCE DEMONSTRATION 

The demonstration of the response and performance of a ATIS system should be specified in the OEM test plan in 

relation to the vehicle type or vehicle combination. In the event that no OEM test plan has been specified, the procedure 

defined below may be used. This procedures is structured to validate that the system as designed and used as intended 

meets or exceeds the defined response characteristics of this specification, namely, (1) can communicate at the 

driver/operator indicator panel a condition of low pressure in a tire/wheel assembly(ies) or the isolation of the re-inflation 

system from the supply reservoir, and (2) maintains the inflation pressure within the acceptable operating pressure range. 

Regardless of test method used, appropriate safety procedures and safety equipment must be utilized. 

6.1 Vehicle Test (Power Unit, Trailers, Dollies) 

6.1.1 Test Setup 

The test vehicle should be equipped with an operationally ready A TIS system, and if the test vehicle is a trailer, with the 

trailer attached to a power unit and all associated connections made. 

a. Set the tire pressure to the operational service pressure for the vehicle(s) under test. Condition the vehicle for 1 h 

outdoors- stationary, and tires shaded. The ambient temperature should not vary more than 20 oF (11.11 °C) over the 

test interval. 

b. Reset the tire pressures. Consider the tire stabilized if within ±1 psi after 10 min. 

c. If applicable, conduct a reset of the A TIS system in accordance with the instructions specified in the vehicle owner's 

manual. 

d. With the vehicle stationary and beginning with the ignition locking system in the "Lock" or "Off' position, turn the 

ignition to the "On" or "Run" position. 

e. Allow the on-board compressed air system to reach its operational pressure level, and then command a release of the 

brakes on the trailer allowing the flow of compressed air to the tire pressurization system. 

6.1.2 Test - Vehicle Stationary 

Phase I - The steps of Phase I should be conducted one tire/wheel assembly at a time, and with the vehicle stationary. If 

the A TIS system does not function with the vehicle stationary proceed to 6.1.3. 

a. Release pressure from one tire/wheel assembly on each supply branch of the A TIS system of each included vehicle 

(power unit, trailer, dolly) under test. Reduce the pressure to a gauge reading of 95% of the SSP. 

b. If the re-inflate system has not activated for each assembly under test on or before a gauge pressure reading of 95% 

of SSP, discontinue any further testing. 

c. If the re-inflate system has activated, record the pressure level of each deflated tire/wheel assembly at the point for 

which the system activates, and note whether the indicator panel message lamp (dash or external mount) has been 

activated, and remains activated, as long as the re-inflate system is active. 

d. At the point that the re-inflate system de-activates, record the gauge pressure of the re-inflated tire/wheel assembly, 

and note whether the indicator panel message lamp has been de-activated. 

e. At the end of each test sequence: (1) validate that the system's performance meets the threshold criteria specified in 

this document, and (2) validate that the information displayed on the indicator panel has communicated the system's 

response to the demand for inflation pressure. If the criteria has not been met, discontinue any further testing. 
ilo\\lil•~uhtlllollt"\\1 llhllt.tllnll I • \IC Ull 111111,1,\ l)~,~,.._uJ, IS !)ll 

SAE J2848-2 Issued JUN2011 Page 14 of 15 

Phase II - The steps of Phase II should be conducted one tire/wheel assembly at a time. 

a. Release pressure from one tire/wheel assembly of each included vehicle (power unit, trailer, dolly) under test at a rate 

greater than the system's ability to restore pressure. Keep the pressure release valve open for the duration of this 

test. 

b. If the re-inflate system has not activated for each assembly under test on or before a gauge pressure reading of 95% 

of SSP, discontinue any further testing. 

c. If the re-inflate system has activated, record the pressure level of each deflating tire/wheel assembly at the point for 

which the system activates, and note whether the indicator panel message lamp (dash or external mount) has been 

activated, and remains activated, as long as the re-inflate system is active. 

d. At the point that the re-inflate system has been isolated from the supply reservoir, record the gauge pressure of the 

tire/wheel assembly, record the gauge pressure level of the supply reservoir, and note whether the indicator panel 

message lamp remains on. 

e. Stop releasing pressure from the test assembly. Allow the system to restore the pressure to the specified level. 

f. At the end of each test sequence: (1) validate that the system's performance meets the threshold criteria specified for 

supply reservoir isolation, and (2) validate that the information displayed on the indicator panel has communicated the 

system's status. If the criteria has not been met, discontinue any further testing. 

6.1.3 Test: Vehicle Rolling Test (for re-inflate systems which only function while rolling) 

Phase I 

a. Begin driving the vehicle. Achieve a speed of at least 25 mph. 

b. Release pressure from one tire/wheel assembly on one supply branch of the ATIS system of one of the included 

vehicles (power unit, trailer, dolly) under test. Reduce the pressure to a gauge reading of 95% of the SSP. 

c. If the re-inflate system has not activated for each assembly under test on or before a gauge pressure reading of 95% 

of SSP. discontinue any further testing. 

d. If the re-inflate system has activated, record the pressure level of the deflated tire/wheel assembly at the point for 

which the system activates. and note whether the indicator panel message lamp (dash or external mount) has been 

activated, and remains activated, as long as the re-inflate system is active. 

e. At the point that the re-inflate system de-activates. record the gauge pressure of the re-inflated tire/wheel assembly, 

and note whether the indicator panel message lamp has been de-activated. 

f. Repeat the steps of a. through e. for each tire/wheel assembly on each supply branch of the ATIS system of each 

included vehicle (power unit, trailer, dolly) under test. 

g. At the end of each test sequence: ( 1) validate that the system's performance meets the threshold criteria specified in 

this document, and (2) validate that the information displayed on the indicator panel has communicated the system's 

response to the demand for inflation pressure. If the criteria has not been met, discontinue any further testing. 
SAE J2848-2 Issued JUN2011 Page 15 of 15 

Phase II -The steps of Phase II should be conducted one tire/wheel assembly at a time. 

a. Begin driving the vehicle. Achieve a speed of at least 25 mph. 

b. Release pressure from one tire/wheel assembly of the vehicle (power unit, trailer, or dolly) under test at a rate greater 

than the system's ability to restore pressure. Keep the pressure release valve open for the duration of this test. 

c. If the re-inflate system has not activated for the assembly under test on or before a gauge pressure reading of 95% of 

SSP, discontinue any further testing. 

d. If the re-inflate system has activated, record the pressure level of the deflating tire/wheel assembly at the point for 

which the system activates, and note whether the indicator panel message lamp (dash or external mount) has been 

activated, and remains activated, as long as the re-inflate system is active. 

e. At the point that the re-inflate system has been isolated from the supply reservoir, record the gauge pressure of the 

tire/wheel assembly, record the gauge pressure level of the supply reservoir, and note whether the indicator panel 

message lamp remains on. 

f. Stop releasing pressure from the test assembly. Allow the system to restore the pressure to the specified level. 

g. At the end of each test sequence: (1) validate that the system's performance meets the threshold criteria specified for 

supply reservoir isolation, and (2) validate that the information displayed on the indicator panel has communicated the 

system's status. If the criteria has not been met, discontinue any further testing. 

h. Repeat the steps of a. through f. for each tire/wheel assembly on each supply branch of the ATIS system of each 

included vehicle (power unit, trailer, dolly) under test. 

7. NOTES 

7.1 Marginallndica 

A change bar (I) located in the left margin is for the convenience of the user in locating areas where technical revisions, 

not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document 

title indicates a complete revision of the document. including technical revisions. Change bars and (R) are not used in 

original publications, nor in documents that contain editorial changes only. 

PREPARED BY THE SAE TRUCK AND BUS TIRE PRESSURE MANAGEMENT SYSTEMS COMMITTEE 

OF THE SAE TRUCK AND BUS TOTAL VEHICLE STEERING COMMITTEE