This SAE Recommended Practice defines diagnostic test modes, and request and response messages, necessary to be supported by vehicle manufacturers and test tools to meet the requirements of the California OBD II regulations, which pertain to vehicle emission-related data only. These messages are intended to be used by any service tool capable of performing California OBD II mandated diagnostics. Diagnostic Test Modes included in this document are: For each test mode, this document includes:
- a Functional descriptions of test mode
- b Request and response message formats