How do I get a wiring diagram for my fifth wheel trailer? How do I get a wiring diagram for my fifth wheel trailer? I have a 1992 Excel Fifth Wheel RV. Running lights have all stopped working. How do I access the wiring to locate or bypass the problem? We own a 1992 prowler fifth wheel camper and are having wiring problems. Rv Trailer Plug Wiring Diagram | Non - Pinterest Non Commercial Truck, Fifth Wheel and Travel Trailer Wiring Diagram 2004 Chevy Silverado Outlet Wiring Toy Hauler Trailer Light Wiring Trailer Wiring Diagram Fifth Wheel and Gooseneck Wiring | etrailer This 7-way plug is hardwired into your OEM wiring near your rear bumper and provides a 7-pole connector in your truck bed to use when you want to tow a fifth-wheel or gooseneck trailer.