Principles of Operation
WARNING: This page is about a different car, the 2006 Ford F550 Super Duty, 2006 Ford F450 Super Duty, and 2006 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
Regardless of the key position, the power door lock control switches are powered at all times. The power door lock switches supply voltage to either the lock or unlock circuit based upon the switch position. The door lock actuators then actuate to a lock or unlock position determined by the voltage on the lock or unlock circuit.