Power Locks: Description and Operation

Circuit Description
Battery voltage is applied at all times to the door lock relay and unlock relay. When locking the doors by using the vehicle key or passing down the lock knob, a signal will be sent to the body control module. The control module will ground the relay according to the signal and the doors lock.

The body control module also has an input from the ignition key reminder switch. This input prevents the doors from accidentally being locked when exiting the vehicle with the ignition off and the key left in the key cylinder.