The body control system consists of the body control module (BCM), communications, and various input and outputs. Some inputs, outputs and messages require other modules to interact with the BCM. The BCM also has discrete input and output terminals to control the vehicle's body functions. The BCM is wired to the high speed GMLAN serial data bus, low speed GMLAN serial data bus and Multiple LIN buses and acts as a gateway between them.
This vehicle body control module (BCM) functions as the power mode master (PMM). The ignition switch is a low current switch with multiple discrete ignition switch signals to the PMM for determining the power mode that will be sent over the serial data circuits to the other modules that need this information; the PMM will activate relays and other direct outputs of the PMM as needed. Refer to Power Mode Description and Operation for a complete description of power mode functions.
The body control module (BCM) in this vehicle functions as a gateway or translator. The purpose of the gateway is to translate serial data messages between the GMLAN high speed bus and the GMLAN low speed bus for communication between the various modules. The gateway will interact with each network according to that network's transmission protocol.
All communication between the BCM and a scan tool is on the high speed GMLAN serial data circuits. A lost communication DTC typically is set in modules other than the module with a communication failure.
The various body control module (BCM) input and output circuits are illustrated in the corresponding functional areas on the BCM electrical schematics. Refer to the Body Control System Schematics for more detailed information.
Body Control Module ReplacementChild Restraint Systems
Rear-Facing Infant Seat
A rear-facing infant seat provides restraint with the seating surface against
the back of the infant.
The harness system holds the infant in place and, in a crash, acts to keep the
infant positioned in the restraint.
Forward-Facing Child Seat
A forward-facing chil ...
Driver or Passenger Seat Back Cushion Frame Replacement
Driver or Passenger Seat Back Cushion Frame Replacement
Callout
Component Name
Preliminary Procedures
Remove the driver or passenger seat. Refer to Driver or Passenger
Seat Removal and Installation
Remove the front seat c ...
Repairs and Inspections Required After a Collision
Warning: Restraint systems can be damaged in a collision. To help
avoid injury and ensure that all parts in need of replacement are replaced:
Replace any seat belt system that was in use during the collision serious
enough to deploy any automatic restraint device such as air bags ...