Expanded Diagnostic Protocol for OBD II Scan Tools

Vehicle E E System Diagnostic Standards Committee

The committee shall increase customer satisfaction and lower product life cycle costs by investigating and recommending standards that will promote more effective diagnosis of vehicle electrical and electronic system problems. The resulting recommended practices will focus on model year 1992 and beyond. However, they may be useful for prior vehicle diagnosis/repair and may serve as a basis for additional recommended practices and pre-model year 1992 vehicles.Vision Statement: A standard disgnostic connector (in a standard location) will be in all vehicles. Pin assignments for a portion of the connector will also be standardized.All vehicles will implement a set of industry standard diagnostic test modes that can be executed over a standard communication data line (i.e., SAE J1850, ISO 9141-2). Industry standard test information will be associated with some of these diagnostic test modes.An OBD II scan tool will be able to utilize a minimum set of standardized diagnostic test modes and test information.A system will be in place that will allow standard electronic access of all E/E diagnostic service information. Future diagnostic legislation will be in harmony with this vision and the resulting SAE Recommended Practices.