Power Door Locks: Notes

Power door lock system consists of front door lock switches, door lock relay, door unlock relay, driver door unlock relay, door actuators in each door and Body Control Module (BCM). Door lock actuators are reversible motors. All door lock and unlock functions are controlled by BCM.

Pressing LOCK button applies battery voltage to BCM input. BCM applies battery voltage to door lock relay coil. Door lock relay closes, applying voltage to lock side of all door lock motors. All except driver door lock actuator are grounded through door unlock relay. Driver door lock actuator is grounded through driver unlock relay.

Pressing UNLOCK button applies battery voltage to BCM input. BCM applies battery voltage to door unlock relay coil and driver door unlock relay coil. Door unlock relay closes, applying voltage to unlock side of all door lock actuators except driver door actuator. Driver door unlock relay closes, applying voltage to unlock side of driver door actuator. All door actuators are grounded through door lock relay.