Power Door Lock System Description

The automatic door lock system has several features, controlled by the Body Control Module (BCM), which are listed below. The door lock switches and the door lock cylinder tamper switch sends an input to the BCM. The BCM then controls the door lock and actuators through relays.

If any door is opened and the key is in the ignition cylinder, the Body Control Module (BCM) will not lock the doors when the door lock switch is pressed. This prevents the keys from being locked in the car. If the door lock switch is held for more than three seconds, this feature will be overridden and the doors will lock.

When the ignition is in the RUN position, all doors are closed, and the vehicle is shifted out of park, the Body Control Module (BCM) will lock all the doors. When the vehicle is shifted into park, all doors will unlock. The unlock portion of this feature can be disabled either by using the TECH 2, or by key FOB sequence.

B+ is supplied to the stop lamp switch by fuse #2.The stop lamp switch feeds B+ to the transmission control selector switch. Ground is provided to the transmission control selector switch from G103.When the transmission is shifted out of the PARK position, terminal B01 of the BCM connector C1 is grounded. When the Body Control Module (BCM) detects that this terminal has been grounded, it internally grounds terminal D02 of connector C2.This energizes the door lock relay. All of the side door lock actuators activate and lock all the doors.

When the transmission is shifted into the PARK position, ground is removed from terminal B01 of the BCM connector C1.When the BCM detects that the ground has been removed from this terminal, it internally grounds terminals C10 and C11 of connector C2. Terminal C10 energizes the driver door unlock relay which unlocks the driver's door. Terminal C11 energizes the door unlock relay which unlocks the remaining three doors.