All Trailers Lights Work but The Running Lights

Question:

Hi. I have a jeep liberty 2005 and a 7 prong trailer plug ,i bought the adaptor from a 7 prongs to a 4 prongs plug Everything is pluged right green with green yellow with yellow and the 2 browns to the brown. White is connected to the frame so far so good Brake lights work,hazards work,flasher works, but as soon as I put parking lights everything stops working I got power on the brown wire at the beginning of my plug but no power gets to the light and all wirering is bran new no cuts no pinch I am confuse. Need help

asked by: Stephan

Expert Reply:

This sounds like a ground issue. Ground problems normally show up when there is more draw on a system such as when you have the running lights on and then use another function like a turn signal or brake light, but can show up any time.

Make sure that the vehicle side and trailer side connectors are clean and free of corrosion inside and out. The main connector grounds should be attached to clean and corrosion free bare metal surfaces.

The light grounds should also be attached to clean and corrosion free bare metal surfaces. If there is anything between a light ground and the metal trailer frame or if the trailer has an aluminum frame, tilt bed, or folding tongue, any of these things can interrupt the ground. Running jumper wires from the light grounds to the main trailer connector ground can help.

If this is not the problem and you need further troubleshooting advice, please let me know and I would be glad to help.

expert reply by: Conner L