Protocol
OBD-II
On-Board Diagnostics · SAE J1979
Legislated light-vehicle diagnostics exposing PIDs and DTCs through a standard connector. Modern cars carry OBD on CAN (ISO 15765); older fleets used K-Line or PWM/VPW. Service modes (01 live data, 03 DTCs, 04 clear, and others) sit above the transport of the day.
Domains
Layers
Tags
diagnosticspidsdtcemissions
Sources
- SAE J1979
- ISO 15031
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