Troubleshooting a Trailer Right Brake Light Won't Function

Question:

I have a 2007 Jeep commander and have brought it to two different mechanic shops and they have tested one of which used a 4-way LED trailer light tester and told me the trailer lights should work. But, the the right brake light on my trailer does not work! Blinker works which relates to the same wire green, and I think light bulb, as the brake light does. I got an entire new trailer light kit for the right side and same result. Both 4 pin connectors are new along with everything else including wire and lights. Any thoughts would be appreciated, Thanks!

asked by: Tyler

Expert Reply:

It sounds like the problem is on the trailer and is ground related. I would inspect the grounds of the light assembly you have installed on the right side of your trailer and make sure it is connected to a clean metal surface. A lot of assemblies ground through their mounting hardware so you will want to make sure that the assemblies are connected to a clean metal surface. The brake lights will require a better ground than the blinker since it only illuminates one circuit for the blinker.

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

expert reply by: Jameson C