WARNING: This page is about a different car, the 2007 Ford Pickup, 2007 Ford F550 Super Duty, 2007 Ford F450 Super Duty, and 2007 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
Disconnect and detach the driver safety belt buckle switch electrical connector.
Fig 1: Locating Driver Safety Belt Buckle Switch Electrical Connector