Driver and Passenger Door Lock and Unlock-w/ Keyless Entry Option Operation

WARNING: This page is about a different car, the 2003 Pontiac Sunfire and 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.

Pressing LOCK on either door lock switch sends a signal to energize the door lock relay portion of the door lock/unlock relay and also sends a signal to the BCM. When the door lock relay portion of the door lock/unlock relay is energized, the door lock actuator lock control circuits are switched to battery positive voltage. The passenger door lock actuator unlock control circuits are grounded through the door unlock relay portion of the door lock/unlock relay and the driver door lock actuator unlock control circuit is grounded through the BCM, completing the path to ground, energizing all of the door lock actuators, locking all the doors.

The lock function can also be accomplished by the BCM having received a keyless entry door lock command.

Pressing UNLOCK on either door lock switch sends a signal to energize the door unlock relay portion of the door lock/unlock relay and also sends a signal to the BCM. When the door unlock relay portion of the door lock/unlock relay is energized, the door lock actuator unlock control circuits are switched to battery positive voltage and the BCM switches the driver door lock actuator unlock control circuit to battery positive voltage. The door lock actuator lock control circuits are grounded through the door lock relay portion of the door lock/unlock relay, completing the path to ground, energizing all of the door lock actuators, unlocking all the doors.

The unlock function can also be accomplished by the BCM having received a keyless entry door unlock command. Keyless entry personalization allows the driver door to be unlocked individually before unlocking the passenger doors. When this feature is active, the BCM will require a repeated unlock command to unlock the passenger doors.