SAEJ1979是OBD2协议的标准规范

This document supersedes SAE J1979 SEP1997, and is technically equivalent to ISO/DIS 15031-5:April 30, 2002, except for minor reorganisation of Paragraphs 1 and 2. Foreword—On-Board Diagnostic (OBD) regulations require passenger cars, and light and medium duty trucks, to support communication of a minimum set of diagnostic information to off-board “generic” test equipment. This document specifies diagnostic services and functionally addressed request / response messages required to be supported by motor vehicles and external test equipment for diagnostic purposes which pertain to motor vehicle emission-related data. These messages are intended to be used by any external test equipment meeting the requirements of SAE J1978 for retrieval of OBD information from a vehicle.