Chevrolet Sonic Repair Manual: Body Control System Description and Operation
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.
- Power Mode Master
-
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.
- Gateway
-
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.
- Body Control
-
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 Replacement
Body Control Module Replacement
Callout
Component Name
Preliminary Procedure
Remove the instrument panel lower trim pad cover. ...
Other materials:
Rear Bumper Impact Bar Replacement (Sedan)
Rear Bumper Impact Bar Replacement
Callout
Component Name
Preliminary Procedure
Remove the rear bumper fascia. Refer to Rear Bumper Fascia Replacement.
1
Rear Bumper Impact Bar Bolt (Qty:?€‰4 ...
Inflatable Restraint Remote Impact Sensor Replacement
Inflatable Restraint Remote Impact Sensor Replacement
Callout
Component Name
Warning: When performing service on or near the SIR components
or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling
a ...
Tire and Wheel Assembly Runout Measurement - On-Vehicle
Raise and support the vehicle.
Closely inspect each tire for proper and even bead seating.
If any of the tire beads were not properly or evenly seated, reseat the
tire bead, then proceed to step 4. Refer to Tire and Wheel Removal and Installation.
Wrap the circumferenc ...
0.0047