Vehicle OBD II Compliance Test Cases
The main purpose of this Recommended Practice is to verify that vehicles are capable of communicating a minimum
subset of information, in accordance with the diagnostic test services specified in SAE J1979: E/E Diagnostic Test Modes,
or the equivalent document ISO 15031-5: Communication Between Vehicle and External Equipment for Emissions-
Related Diagnostics – Part 5: Emissions-related diagnostic services.
Any software meeting these specifications will utilize the vehicle interface that is defined in SAE J2534, Recommended
Practice for Pass-Thru Vehicle Programming.
Rationale:Corrections have been made to this document in order to keep pace with and agree with changes made to the California
Air Resources Board legislation: Title 13, California Code Regulations, Section 1968.2, Malfunction and Diagnostic
System Requirements for 2004 and Subsequent Model-Year Passenger Cars, Light-Duty Trucks, and Medium-Duty
Vehicles and Engines (OBD II), particularly with regards to permanent DTCs and new diesel engine requirements. Many
functional enhancements have also been included in this document.