Powertrain Control Module: Notes

For location of PCM, see COMPONENT LOCATIONS in appropriate SYSTEM & COMPONENT TESTING article. The PCM constantly monitors information from various sensors to control fuel flow, injector timing, cruise control, transmission shifting, throttle, EGR, TCC, cold advance and glow plug systems. PCM processes input signals from sensors and then sends necessary electrical responses to control these systems.

The PCM performs the diagnostic function of the system. It can recognize operational problems, alert driver through the Malfunction Indicator Light (MIL) and store DTCs which identify problem areas to technicians to aid in making system repairs.