Powertrain Control Module (PCM)

The PCM is responsible for maintaining proper spark and fuel injection timing for all driving conditions. To provide optimum driveability and emissions, the PCM monitors input signals from the additional following components in calculating Ignition Control (IC) spark timing:
^ The Engine Coolant Temperature (ECT) sensor
^ The Intake Air Temperature (IAT) sensor
^ The Mass Air Flow (MAF) sensor
^ The trans range inputs from the transmission range switch (PRND)
^ The Throttle Position (TP) sensor
^ The Vehicle Speed Sensor (VSS)