Troubleshooting Trailer Running Light Wiring Circuit Not Active When Vehicle Connector Tests OK

Question:

Ive ran a tester on my Durmax 7- pin trailer plug in . Everything works blinkers, brake lights , Flashers , running lights . 2005 Durmax Chevolet . Then when I plugged in the trailer to the truck , all I got is brake lights , blinkers , hazard lights. I got no inch Running Lights . All the fuses are good also . Help ! I been working on this for weeks with no results .

asked by: Rick S

Expert Reply:

Sounds like you probably have some corrosion or dirt on the running lights pin of your trailer wiring which is preventing the connection from being made and not allowing the lights to come one. Or it's possible the pin is bent or damaged. I'd try cleaning the pins with some sand paper and inspecting them to see if that's the issue.

If that's not the issue it's most likely a ground issue on the taillights or there's damage to the power wire for the running light circuit that runs to the assemblies.

I attached a help article on troubleshooting trailer wiring for you to check out as well.

expert reply by: Jameson C