Security System
WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
The PASSLOCK™ sensor is powered by circuit 812. The PASSLOCK™ sensor is grounded by circuit 1057. PASSLOCK™ sensor data is supplied to the 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.