What Does the BCM Do in My Cadillac?by Nanette Delaney Burton
First introduced on the 1985 C-body Cadillac, the body control module (BCM) has been used on Cadillac systems ever since. The BCM interacts and exchanges information with the powertrain control module (PCM) and is a smaller version (with all the same parts) of the engine computer, but responsible for controlling different functions.
The body control module is responsible for controlling the climate in a Cadillac. The electronic climate control -- air conditioning (A/C) unit - and the cooling fans that draw air through the A/C condenser and radiator are functions of the BCM.
The Cadillac's power windows, sunroof and trunk release are also functions controlled by the body control module.
Information Display Panel
When driving a Cadillac, drivers are displayed information on the information display panel, which adjusts for visual clarity under different driving conditions, controlled by the BCM.
Self-Monitoring for Faults
A major function of the BCM system is the ability to monitor itself, providing fault codes when faults are found. In some cases, the BCM uses this information to provide fail-safe measures to compensate for system failure.