The Expedition is a full-size sport utility vehicle that has been produced by Ford since 1996. Because of its considerable weight and wheelbase the Expedition is ideal for towing light and medium-weight trailers. All models of the vehicle are factory-equipped with a tow package, a flat four-pin hitch and a port, located under the dash to the right of the steering column which makes the fitting of a brake controller a simple project. Once an electronic brake controller is in place and its harness installed in the port, wiring the brakes is an extremely straightforward project.
Follow the four-conductor trailer lighting harness beneath the Expedition, backward from the flat four-pin hitch to where it enters a protective sheath. At the protective sheath, locate a dead tail wire also emerging from the sheath, color-coded dark blue. This wire is the signal wire from the electronic brake controller port to the trailer brakes.
Route loose 12-gauge wire, also color-coded blue, to the location of the round seven-pin hitch that will be necessary to operate a trailer fitted with electric brakes. Because of its location under the vehicle, the connection to the preexisting wire is better made with a soldered joint insulated with a shrink-wrap kit than with a cable splice.
Use plastic cable ties approximately every 10 inches along the run of new wire to secure it away from hot and moving components.
Attach the end of the new blue wire to terminal two of the round seven-pin hitch when it has been installed.
