Normal Operation
WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The seat control switch is powered by battery voltage through circuit 171 (BK/WH) and is grounded by circuit 57 (BK). The seat control switch then routes power and ground to the appropriate circuits to operate the seat motors.