This SAE recommended practice defines the system and component functions, measurement metrics, testing methodologies for evaluating the functionality and performance of ground vehicle CTIS. Systems of this type allow the driver to select the operational tire pressure set point (TPSP) based on off-highway conditions, and, upon returning to highway operations, maintain the inflation pressure to the vehicle specified level.

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.

Systems for use by military and some other very rigorous off-road applications require such extreme performance requirements, particularly at very high and low temperature and other combat-based extremes that such applications may fall outside the recommended parameters of the subject document. In those cases, it's the responsibility of the procuring customer, vehicle OEM, and applicable component(s) OEM to determine what compromises might be required, and the suitability of design and performance solutions that may be outside of those recommended here.

This document is applicable to all axle and all wheel combinations for the following vehicle types, but does not preclude it's use on other vehicle types - single unit powered vehicles exceeding 7257 kg (16,000 US lbs) gross vehicle weight rating (GVWR), and multi-unit vehicle combinations, up to three (3) 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 installing a CTIS system, dual tire equalizers systems are not recommended as they run counter to the purpose of the management system.

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

1. Tire Pressure Monitoring Systems - these systems have been addressed under SAE J2848-1.

2. Tire Pressure Maintenance Systems - these systems have been addressed under SAE J2848-2.

Purpose

The installed systems for the management of tire inflation pressure defined herein are on-board vehicle systems only. The management 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 a management type system, and to function within the intended operating environment and design configuration of the vehicle itself.

Tire pressure systems of the management type (CTIS) are intended to -

1. Allow the driver to select the operational pressure level for off-highway operations, based on the operational conditions, within the defined constraints,

2. Maintain the operational TPSP level for the typical range of ambient conditions,

3. Return all tire/wheel assemblies to the vehicle's SSP level upon returning to highway conditions, and to maintain this specified pressure level within the acceptable operating pressure range (AOPR),

4. Provide the driver with indications of system malfunctions and uncorrected pressure levels.