Checking/Fixing Ground Connection on Trailer LED Light Bar

Updated 06/24/2020 | Published 06/23/2020

Question:

Dear E-Trailer, I have a 16, 3 light bar on the rear of my boat trailer. I noticed that one light was not working. Went to replace it and the new one would not work. Goofed around with the bar and all quit working. Move the bar and some would light, some dim some not at all. Put a wedge in the upper end of the bar and all light shine bright. I assume it is a ground but the ground looks good. The bar is 16 years old so maybe time for a new one with new ground. Thanks

asked by: Jim

Helpful Expert Reply:

From what you describe, it sounds exactly like a ground problem. You'll want to make sure the ring terminal on the ground wire is making contact with bare metal on the trailer frame. If there's paint or corrosion preventing the ring terminal from making good metal-metal contact, you'll only pick up the ground connections through the threads of the ground screw, which sometimes isn't sufficient.

To refresh a ground connection, I like to remove the ground screw, sand down the area around the hole down to bare metal. When you install the ground screw and the ring terminal, use a star washer between the ring terminal and the trailer frame. The star washer will bite into the metal, ensuring a good connection. Then, give the connection a quick shot of rust inhibiting spray paint.

I've linked to some help articles about trailer wiring.

expert reply by: Mike L