Troubleshooting Trailer Running Lights That Don't Work Like They Should

Question:

I have a 2018 Jeep JL and I pull a 2018 rpod trailer. I never had light issues until I put a new back bumper with rigid lights in it now when I plug in the 7 pin hitch cable the blinkers and the brake lights work on the trailer but the running lights just flicker then go off on the r- pod trailer. Also when I plug in the driver side of the Jeep the front and back light on the side go off also. I then plugged my friends truck into my rpod trailer and everything worked. I then took the ground wire from the back of the Jeep and scraped the frame bottom of the Jeep and reattached but same problem.. Do you have any ideas.. Thank you very much

asked by: Jeff H

Helpful Expert Reply:

I do have ideas, which is that you almost certainly have an issue with a poor ground. I'm not 100% sure what you meant by "I then took the ground wire from the back of the Jeep and scraped the frame bottom" but you need to make sure your grounds are attached to bare metal surfaces and free of any paint, dirt or corrosion. Is that what you meant by scraping? If so, I'd go over it again and really give it a good, thorough cleaning.

If that doesn't resolve the problem, you will want to check both your vehicle and trailer connectors for corrosion, which can be green or white in color. A build-up of corrosion can interfere with the signals getting through the connectors so if it is present you are going to need to replace the plug or clean it very thoroughly.

I have added links to a pair of help articles on trailer wiring, including a troubleshooting guide which I highly recommend taking a look at.

expert reply by: Kyle S