Troubleshooting Faint Taillight Functions on a Horse Trailer

Question:

not a real wiring-techno type guy here. I have a 7 way RV flat blade plug on a 2004 Diamond bumper pull horse trailer. My 96 Dodge Ram 1500 has the same connector. When I plug the two together I get zero on the side-running lates, and zero on brake/reverse lights. When I hit the turn signals the trailer lights in back show a very, very faint light virtually zero. On the truck end connection I have 4-wires into it: L/R Turn signals Ground Brake controller I need help obviously.

asked by: Jeff C

Expert Reply:

A couple of things could be what's going on. First thing I would do is inspect both trailer connectors on your truck and trailer. Clean off the connection points as it sounds like you have some corrosion that is preventing the connection from being made.

The next place to look is the grounds of the trailer. Each light assembly should be grounded to a clean metal surface. A lot of assemblies ground through the mounting hardware so make sure they are attached to a clean metal surface. Lastly, you want to check the main ground of the trailer wiring. This is the ground wire that runs from the trailer connector to the trailer frame.

I attached a couple helpful FAQ articles to the right for you to check out as well.

expert reply by: Jameson C