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. These relays operate to energize the actuators by applying voltage to one of the terminals and ground to the other terminal. To reverse the actuators, the polarity to the terminals is reversed.

The door lock switches are usually closed for just a moment. If they 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 circuit 195.

This action turns on the lock relay (located inside the door lock relay assembly). The lock relay then completes the circuit that supplies voltage to circuit 295, which is the voltage feed to the actuators.

Note that at this time the unlock relay is not energized. When the unlock relay is off, it grounds circuit 294 which provides a ground path to the door lock actuators.

This action complete the electrical circuit to 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 circuit 194.

This action turns on the unlock relay (located inside the door lock relay assembly). The unlock relay then completes the circuit that supplies voltage to circuit 294, which is the voltage feed to the actuators.

Note that at this time the lock relay is not energized. When the lock relay is off, it grounds circuit 295 which provides a ground path to the door lock actuators.

This action complete the electrical circuit to the actuators in each door, thus unlocking the doors. Note that the polarity of the voltage to the actuators has reversed, causing the actuators run in the opposite direction and unlock the doors.