Corvette V8-5.7L VIN G (1997)
Body Control Module: Description and Operation
Body Control System Operation
BCM Fail-Soft Condition
If a particular Body Control Module (BCM) malfunction would result in unacceptable system operation, the BCM takes a fail-soft action in order to
minimize the condition. A typical fail-soft action would be the substitution of a fixed input or output value when the BCM is unable to interpret data
correctly.
BCM Functions
The Body Control Module (BCM) is capable of performing multiple body control functions. The BCM outputs control the systems that are directly
connected to the BCM. The BCM controls the outputs using this input information received from the sensors and the switches directly connected to the
BCM. The BCM also borrows information from other systems on the serial data line in order to control the outputs. The BCM evaluates this information
and commands an Output ON or OFF in order to control certain body systems. The BCM also commands other systems to control systems that are not
directly wired to the BCM. The BCM accomplishes this by sending specific messages on the serial data line. The system capable of performing this
function will respond to the message.
The BCM is capable of performing the following functions:
^
Bulb over voltage protection
^
Door ajar status
^
Exterior light control
-
Approach lighting
-
Backup lights
-
Daytime Running Lights (DRL)
-
Headlights flash-to-pass feature
-
Front fog lights
-
Front turn signal monitoring
-
Rear fog lamps (export only)
^
Hatch ajar status
^
Hatch release control
^
Heated mirror control
^
Hood ajar status
^
Horn relay
^
Interior light control
-
Center console lights
-
Courtesy lights
-
HVAC illumination
-
Illuminated entry feature
-
Lower courtesy lights
-
PRNDL display
^
Key-in-ignition status
^
Load shed control
^
Monitored loads control
^
Pass-Key(R) (Personalized Automotive Security System)
^
Power mode master
^
Rear defogger control
^
Steering column lock/unlock control
^
TCS activation control
^
Universal Theft Deterrent (UTD)
^
Vehicle configuration (RPO codes)
BCM Input/Output Information
The following components provide direct input to the Body Control Module (BCM). Other systems can use this input information in order to carry out
certain functions:
BCM Inputs
^
Ambient Light Signal Processing - provides the BCM with the ambient light input information for interior lamp illumination.
^
Column Feedback Switch - provides steering column feedback information to the BCM in order to determine if the steering column was
successfully locked or unlocked.
^
Door Ajar Switches - provides door ajar status to the BCM.
^
Electronic Traction/Suspension Control Switch -. provides traction control switch activation input to the BCM in order to turn the TCS status
ON or OFF.
^
Fog Lamp Switch, Front - provides fog lamp switch activation input to the BCM in order to turn the front fog lamps ON or OFF.
^
Fog Lamp Switch, Rear - provides fog lamp switch activation input to the BCM in order to turn the rear fog lamps ON or OFF.
^
Hatch Ajar Switch - provides hatch ajar status to the BCM.
^
Hatch Release Switch - provides hatch release switch information to the BCM.
