GM Service Manual Online
For 1990-2009 cars only

The body control system consists of the body control module (BCM) and its associated controls. Battery positive voltage is provided to the BCM from the STOP/TURN fuse and the CHMSL/BKUP fuse in the fuse block instrument panel (I/P). The module grounds are wired to ground G200, G201 and G301. 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 the power mode functions.

Body Control Module

The various body control module (BCM) input and output circuits are described in the corresponding functional areas indicated on the BCM electrical schematics. The BCM functions include the following:

    • Battery rundown protection--Inadvertent power--Refer to Interior Lighting Systems Description and Operation in Lighting Systems.
    • BTSI/automatic transmission shift lock control--Refer to Automatic Transmission Shift Lock Control Description and Operation in Automatic Transaxle - 4T65-E.
    • Bulb check--Refer to Instrument Cluster Description and Operation in Instrument Panel, Gages, and Console.
    • Chimes--Refer to Audible Warnings Description and Operation in Instrument Panel, Gages, and Console.
       - Check gages
       - Content theft deterrent
       - Door ajar warning
       - Headlamps ON
       - Key-in-ignition
       - Oil reset
       - Park brake warning
       - Seat belt not fastened
       - Turn signal ON
       - Vehicle theft deterrent
    • Door lock interface--Refer to Power Door Locks Description and Operation in Doors.
    • Exterior and interior lighting control--Refer to Exterior Lighting Systems Description and Operation in Lighting Systems.
       - Automatic lighting control
       - Backup lamps
       - Daytime running lights (DRL)
       - Fog lamps
       - High/low beam head lamps
       - Park brake lights
       - Turn hazard lamps
    • Gage control--Refer to Instrument Cluster Description and Operation in Instrument Panel, Gages, and Console.
    • Heated seats--Refer to Heated Seats Description and Operation in Seats.
    • Horn interface--Refer to Horns System Description and Operation in Horns.
    • Instrument cluster indicator control--Refer to Instrument Cluster Description and Operation in Instrument Panel, Gages, and Console.
    • Interior lighting--Refer to Interior Lighting Systems Description and Operation in Lighting Systems.
    • Key-in-ignition sensing--Refer to Audible Warnings Description and Operation in Instrument Panel, Gages, and Console.
    • Parking brake state sensing--Refer to Brake Warning System Description and Operation in Hydraulic Brakes.
    • Retained accessory power (RAP)--Refer to Retained Accessory Power (RAP) Description and Operation in Retained Accessory Power.
    • Rear compartment interface--Refer to Power Door Locks Description and Operation in Doors.
    • Rear defogger--Refer to Rear Window Defogger Description and Operation in Stationary Windows.
    • Remote function control--Refer to Keyless Entry System Description and Operation in Keyless Entry.
    • RFA communication link--Refer to Keyless Entry System Description and Operation in Keyless Entry.
    • Seat belt use sensing--Refer to Seat Belt System Description and Operation in Seat Belts.
    • Theft deterrent vehicle/content--Refer to Theft Systems Description and Operation in Theft Deterrent.
    • Washer solvent level sensing--Refer to Wiper/Washer System Description and Operation in Wipers/Washer Systems.
    • Wiper/washer--Refer to Wiper/Washer System Description and Operation in Wipers/Washer Systems.