Description & Operation

NOTE: On some vehicles, the power door lock system is integrated with the Remote Keyless Entry (RKE) system. For information on RKE, see appropriate REMOTE KEYLESS ENTRY SYSTEMS article.

When door lock switch is operated, all doors will lock or unlock. Each lock can also be operated manually. Locks are operated by reversible motors. Door lock switches operate relays which turn motors on by supplying battery voltage to one terminal and ground to the other terminal.

When any door lock switch is moved to LOCK position, switch completes a circuit to the door lock relay. The relay closes, supplying voltage to door lock motors in each door to operate door locks. When door lock switch is released, circuit is opened and motors turn off. When door lock switch is moved to UNLOCK position, the unlock relay is energized and polarity of voltage to motors is reversed. Driver door unlock is controlled through driver unlock relay by Body Control Module (BCM). When door lock switch is moved to UNLOCK position, battery voltage is also sent to BCM which intern supplies voltage to driver door unlock relay. Driver door unlock relay closes, supplying voltage to driver door actuator to unlock door.

Door lock switches are usually closed for just a moment. If door lock switches are held closed for an extended time, a circuit breaker in each motor will open to protect motor against damage. Circuit breakers close automatically when they cool down.