Car wiring diagrams: Ford F150 Trailer Wiring Not Working, wiring diagram, wire wiring harness, schematic circuit diagram, wiring diagran, wireing diagram, wirring diagram, wiring daigram, wiring diagrams. Free Shipping on Ford F Towing Hitches at AutoAccessoriesGarage.com. Browse Ford F online or call today.. Video embedded Videos are provided as a guide only. Refer to . Video embedded This is an instructional video on how to add a Ford OEM trailer brake controller to a F that did not come with one from the .