subject: Functionality of Powertrain Control Module (PCM) in OBD II Diagnostics [print this page] Functionality of Powertrain Control Module (PCM) in OBD II Diagnostics
The PCM communicates with the OBD II scan tool and provides diagnostic data, and OBD II DTCs of all faults experienced by the vehicle so far to the external tester to facilitate off-board diagnostics, and vehicle repair. In this respect OBD II provides SAE J 1850 data link for communication of diagnostic data, SAE J 2012 provides the DTC message formats, and SAE J 1979 provides the test modes, requesting PCM for emissions related powertrain diagnostics data.
