Functional Description - Powertrain Control Module (Pcm)

The Powertrain Control Module (PCM) is responsible for engine operation and monitoring the low voltage battery system. The PCM determines the rate of charge needed for the low voltage battery and communicates this to the Integrated Dual Charging Module (IDCM). The Auxiliary Power Module (APM) inside the IDCM replaces the function of the alternator on a Plug-in Hybrid Electric Vehicle. The PCM will set a DTC if the system voltage is too low or too high. When the PCM determines there is a system voltage failure, the PCM will send a message to the Instrument Cluster to illuminate the check gauges lamp (if equipped) or display a charging system error message with the engine running.