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A Diagnostic Starting Point - Body Control System

The diagnostic flow charts contained are used to find and repair malfunctions which the self-diagnostics of the module have found. If a Diagnostic Trouble Code (DTC) is a history DTC, the malfunction may be intermittent. Try wiggling wiring and connectors as this can often cause the malfunction to appear. It is not recommended to replace modules based on history codes.

It is recommended to use a Scan tool in performing system diagnostics. The Scan tool displays (shown in the diagnostics) will assist in diagnosing Body Control Module (BCM) related malfunctions. The diagnostic flow charts in this manual rely on data from a Scan tool to make repair decisions. Do not use a BCM from another vehicle to aid in diagnosis. BCM's are not interchangeable after they have been installed.