GM Service Manual Online
For 1990-2009 cars only

The body control system consists of a body control module (BCM) and its associated controls. Battery positive voltage is provided to the BCM from BFC/BATT fuse in the left hand instrument panel fuse block. The module ground is wired to ground G202. The BCM is wired to the Class 2 serial data communication bus as well as discrete input and output terminals to control the functions of the vehicles body .

Power Mode Master

This vehicles BCM functions as the Power Mode Master (PMM). Refer to Power Mode Description and Operation for a complete description of power mode functions.

Body Control Module

The various BCM input and output circuits are described in the corresponding functional areas indicated on the BCM electrical schematics. The Body Control Module functions include the following:

    • A/C compressor request. Refer to Air Temperature Description and Operation
    • Remote Function Control. Refer to Keyless Entry System Description and Operation
    • A/C cooling Fan. Refer to Air Delivery Description and Operation
    • Audio Delay Power. Refer to Radio/Audio System Description and Operation
    • Exterior and interior lighting control. Refer to Exterior Lighting Systems Description and Operation
       - Daytime running lights (DRL)
       - Automatic lighting control
       - Fog lamps
    • Interior lighting. Refer to Interior Lighting Systems Description and Operation
    • Battery rundown protection (Inadvertent Power). Refer to Interior Lighting Systems Description and Operation
    • Chimes. Refer to Audible Warnings Description and Operation
       - Key-In-Ignition
       - Head Lamps On
       - Seat Belt Not Fastened
       - Turn Signal On
       - Park Brake Warning
       - Door Ajar Warning
       - Check gages
    • Gage control. Refer to Instrument Cluster Description and Operation in Instrument Panel, Gages, and Console.
    • Instrument cluster indicator control. Refer to Instrument Cluster Description and Operation in Instrument Panel, Gages, and Console.
    • Theft deterrent. Refer to Theft Systems Description and Operation .
    • Engine coolant level sensing. Refer to Cooling System Description and Operation .
    • Washer solvent level sensing. Refer to Wiper/Washer System Description and Operation in Wipers/Washer Systems.
    • Key-in-ignition sensing. Refer to Audible Warnings Description and Operation in Instrument Panel, Gages, and Console.
    • Seat belt use sensing. Refer to Seat Belt System Description and Operation .
    • Brake fluid level sensing.
    • Parking brake state sensing.
    • Rear compartment interface. Refer to Power Door Locks Description and Operation
    • Horn interface.
    • Door lock interface. Refer to Power Door Locks Description and Operation
    • Bulb Check. Refer to Instrument Cluster Description and Operation in Instrument Panel, Gages, and Console.