DTC B3033: Security System Indicates Tamper: Notes

Fig 1: B3033 - Security System Indicates Tamper Schematic

Courtesy of GENERAL MOTORS CORP.

Passlock sensor data is supplied to the Body Control Module (BCM) by circuit 1836.

The passlock sensor data supplied to the BCM is in the form of V-codes or voltage codes. When the proper ignition key is turned in the ignition switch, the correct V-code is supplied to the BCM. The BCM responds by sending a serial data password to the engine controller allowing the engine to run.

The security resistor is bypassed under a tamper condition (possible external magnet applied to sensor). In this mode, a specific V-code is supplied to the BCM. The vehicle will not start in this mode.