Troubleshooting Trailer Wiring That Blows Fuse When Put in Reverse

Question:

Hi, I have a 2004 Lexus GX470 and a camper. When I connect the camper to the car and drive it, everything works well. But the moment I put it in reverse, a fuse blows and I lose turn signals. I tested the camper on another vehichle without any problems. Any suggestions on what could be causing this issue? Thanks

asked by: John P

Expert Reply:

Sounds like somehow there's a short between the reverse light circuit of your trailer wiring on your vehicle and the rest of the trailer wiring. What I would recommend you do is use a circuit tester like part # PTW2993 to test the pins of your trailer wiring like what the attached video link shows and then repeat the test with the reverse lights on too to see what circuit might have the short. If the trailer wiring of the vehicle was aftermarket and installed by you or someone else I'd suspect the issue is somewhere related to the connections made there.

I attached a help article on trailer wiring troubleshooting for you to check out as well.

expert reply by: Jameson C