Powertrain Control Module

The PCM has the capability to diagnose faults in the sensors, input switches, components and system it controls. When the PCM recognizes a problem, it turns on the "Service Engine Soon" telltale lamp on the instrument panel to alert the driver that a malfunction has occurred. The PCM will also send a message to the Body Control Module (BCM) to turn on the "Service Car" message on the Driver Information Center (DIC).