For 1990-2009 cars

Important: DO NOT replace the body control module (BCM) unless a diagnostic trouble code (DTC) remains current after all of the DTC tables are executed. Do not replace the BCM based on the history codes.

The BCM is connected to the Class 2 serial data link. The BCM is capable of setting DTCs. A history DTC is a malfunction that disappears in the next ignition cycle. The history DTCs may be especially useful in diagnosing an intermittent problem. An explanation of the history DTCs are given below in the DTC table.

Diagnostic Trouble Code | Explanation
--- | ---
Passlock™ Theft Deterrent
B2947 | DTC B2947 Security System Sensor Power CKT Low
B2948 | DTC B2948 Security System Sensor Power CKT High
B2957 | DTC B2957 Security System Sensor Data Circuit Low
B2958 | DTC B2958 Security System Sensor Data Circuit High
B2960 | DTC B2960 Invalid Coded Key Present
B3031 | DTC B3031 Key Decoder Device in Assem Learn Mode
B3033 | DTC B3033 Security System Indicates Tamper