Power Locks: Description and Operation

CIRCUIT CHART
Circuit assignments for the Body Control Module (BCM) relating to doors and locks:

DOOR LOCKING/UNLOCKING
Door locking/unlocking, by Remote Keyless Entry (RKE) or driver/all door lock switches, is controlled through the BCM.

When a driver door unlock has been requested, the BCM switches circuit 1391 to battery voltage. This energizes the driver door unlock relay which supplies power to the driver door lock motor. Grounding is achieved through the closed contacts of the all-door lock relay. Grounding is also achieved through the windings of the all-door lock motors and the all-door unlock relay.

When an all-door unlock has been requested, the BCM switches circuit 194 to battery voltage. This energizes the door unlock relay which supplies power to the all-door lock motors. Grounding is achieved through the closed contacts of the door lock relay. Grounding is also achieved through the winding of the driver door lock motor and the driver door unlock relay.

When an all-door lock has been requested, the BCM switches circuit 195 to battery voltage. This energizes the door lock relay which supplies power to all-door lock motors. Grounding is achieved through the closed contacts of the door unlock relay and the BCM.

Lock/Unlock power application is limited by the BCM to 7 seconds to protect lock motors.

ANTI-LOCKOUT
To help prevent locking your keys in your car, the BCM will unlock the drivers door when any interior door lock switch is activated, while a door is open and the key is still in the ignition.