Powertrain Control Module (PCM)

The Powertrain Control Module (PCM) is the control center of the engine controls system. It constantly looks at the information from various sensors, and controls the Systems that affect emissions or engine performance. The PCM also performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the Malfunction Indicator Lamp (MIL), and store a DTC or DTCs which identify the problem areas in order to aid the technician in making repairs.