Troubleshooting Trailer Running Light Function Not Working And No Turn Signals

Updated 03/28/2017 | Published 03/27/2017

Question:

My wiring on my trailer pigtail matches my truck pigtail but Im getting no run lights and no turning signals what is my problem I have checked my power to my pigtail and the power on my backside of my trailer I have power to there but I have no power to my run lights for my turning signals what is my problem

asked by: James Z

Expert Reply:

The problem is most likely that the colors don't match the function. I recommend using an incandescent circuit tester like # PTW2993 to check for function at your vehicle connection first. Then determine the function of each wire on the trailer and connect according to function.

If it doesn't work after that, then I would run a jumper wire and see if you get function. If so, you will need to replace that trailer wire because it has a short . If not, you will need to check your ground for metal to metal connection because the circuit isn't connecting correctly and check the trailer connection for corroded areas in need of cleaning. I've attached an article to help.

expert reply by: Jason S