Body Control Module

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2002 GMC Yukon XL, 2002 GMC Yukon, 2002 Chevrolet Tahoe, 2002 Chevrolet Suburban, and 2002 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.

The Body Control Module (BCM) contains the theft deterrent system logic. The BCM reads the Passlock(tm) data from the Passlock(tm) sensor. If the Passlock(tm) data is correct, the BCM will pass theft. The BCM will then transmit the fuel continue password to the VCM/PCM.

During the tamper mode the vehicle may start. The vehicle will then stall. If the BCM receives the wrong Passlock(tm) data, the VTD will immediately go into the tamper mode. The tamper mode will lock-out the vehicle fuel injectors for 10 minutes. The SECURITY indicator will flash while the VTD is in the tamper mode.

If the Passlock(tm) sensor sends a correct password to the BCM when the ignition is in the ON position, the BCM will send a fuel enable signal to the VCM/PCM. The VCM/PCM will not disable the fuel due to any BCM message for the remainder of the ignition cycle.