Powertrain Control Module (PCM)

PCM monitors engine operating conditions by input received from engine sensors. Control of output actuators determines fuel mixture and idle speed. For PCM location, see POWERTRAIN CONTROL MODULE (PCM) LOCATIONS table.

The engine control system consists of the PCM, relays, modules, sensors, switches and actuators. The PCM sends out electrical reference signals to engine sensors and then analyzes the return signals. The engine sensors supply the PCM with specific information, in the form of electrical signals, to determine engine operating conditions. In the event of a sensor or actuator failure, the PCM initiates an alternative strategy called Failure Mode Effects Management (FMEM) to allow the vehicle to maintain driveability.

Malfunction Indicator Light (MIL) will remain on whenever FMEM is in operation. FMEM substitutes a fixed sensor signal and continues to monitor failed sensor. If signals from a faulty sensor return to within operating limits, PCM will resume using the sensor's signal.