Body Control Modules: Description

The Body Control Module (BCM) controls many vehicle functions. These functions include A/C compressor, audible warnings (chime), battery rundown protection, instrument panel cluster indicators and gauges, interior and exterior lighting, theft deterrent, keyless entry, rear compartment release, shift lock control (A/T) and panic horn.

The BCM communicates with other systems over a serial data line to execute various vehicle functions. Communication between each system is accomplished by sending digitally coded messages, which consist of specific information the system module must follow. Each system module is assigned its own recognition code, so that it can respond to appropriate messages.

Other modules that communicate with the BCM over this line are the Electronic Brake Control Module (EBCM), Powertrain Control Module (PCM), Instrument Panel Cluster (IPC) and the inflatable restraint Sensing and Diagnostic Module (SDM).