Models Without Keyless Entry

When either door lock switch is pressed in the power door locks system, all doors lock or unlock in unison. Each lock can also be operated manually from the locking knob.

The locks are operated by reversible actuators that receive voltage from the door lock relay assembly's two built-in relays. The relays energize the actuators by applying voltage to one of the terminals and ground to the other terminal. In order to reverse the actuators, the polarity to the terminals is reversed.

The door lock switches are usually closed briefly. If the door lock switches are held closed, a circuit breaker in each actuator will open to protect against damage. The circuit breaker resets only after voltage is removed from the actuator.

Lock Operation
Pressing the lock position on either door lock switch sends a voltage signal in CKT 195.

Pressing the lock position turns on the lock relay located inside the door lock relay assembly. The lock relay completes the circuit that supplies voltage to CKT 295. CKT 295 is the voltage feed to the actuators.
At this time, the unlock relay is not energized. When the unlock relay is off, CKT 294 is grounded, which provides a ground path to the door lock actuators.

The entire action described completes the electrical circuit the actuators in each door, thus locking the doors.

When the door lock switch is released, the lock relay contact closes to ground, and the actuators turn off.

Unlock Operation
Pressing the unlock position on either door lock switch sends a voltage signal in CKT 194.

Pressing the unlock position turns on the unlock relay located inside the door lock relay assembly. The unlock relay completes the circuit that supplies voltage to CKT 294. CKT 294 is the voltage feed to the actuators.

At this time, the lock relay is not energized. When the lock relay is off, CKT 295 is grounded, which provides a ground path to the door lock actuator.

The entire action described completes the electrical circuit to the actuators in each door, thus unlocking the doors. The polarity of the voltage to the actuators has reversed, causing the actuators to run in the opposite direction in order to unlock the doors.