Troubleshooting Truck Wiring Issue Caused By Trailer

Question:

was hooking up someones mess up job, and my tail light gave out on my truck and none of my lights on trailer are working

asked by: Jessy

Expert Reply:

The first thing to do is check your fuses and relays as outlined in your owners manual because it sounds like you have a short circuit that most likely blew a fuse. If your fuses and relays are good then I recommend using a circuit tester like # PTW2993 to test your wires right behind the 7-way for each function to determine if there is a short or if the 7-way is bad. If you find no power on one or more of the wires, you will trace them probing every few feet for a short in your wire. Once you find a working portion of wire, you can replace it with # 16-1-1 sold by the foot. If you can't trace it, you should seek help from a mechanic.

You can test the lights themselves directly with some jump wires to your battery. Some of the lights use a ground connection through the mounting hardware, so you may need to consider that as well.

expert reply by: Jason S