Security System Operation: Notes

The passlock system is designed to prevent vehicle operation if the mechanical key is not used to start the vehicle. The mechanical key, in normal operation, will turn the passlock lock cylinder. The passlock sensor (which is mounted to the passlock lock cylinder assembly) sends data by circuit 1836 to the Body Control Module (BCM). The passlock sensor is powered by circuit 812 from the BCM. The passlock sensor is grounded by circuit 1057 to the BCM. The BCM determines the validity of the passlock sensor data within a preset time window based on ignition switch input. The BCM will then send a coded password to the ECM by the CAN bus circuit 3204 or PCM by class 2, circuit 1807. When the ECM/PCM receives the correct code, it will allow the fuel injectors to operate normally.