Troubleshooting a Trailer With Running Lights That Don't Work

Question:

My running lights on my camper are not working, I have tested my truck and all lights work when hooked up to another trailer. I read a post earlier that said I could jump position 3 and 4 on my plug to see if the running lights would come on then, they did all come on. So my question is, where is my problem located? Also all other lights and brakes work.

asked by: Eric

Expert Reply:

If you've already tested the lights on another trailer and they work, then the issue has to be with your camper. Somewhere in your trailer's wiring there is an issue, so you'll need to go through it and check for damage or broken wires.

I recommend starting with your trailer's connector, though. The simplest things are often overlooked, so I'd start here and look for any signs of corrosion or damage. If the contacts in the connector aren't making a good connection with the tow vehicle this can cause things to not work or work intermittently.

It's also good to check the ground connections while you're examining your wires. Something as simple as a loose or poor ground connection can cause this type of thing to happen.

expert reply by: Bryce D