Running Lights Not Working on 4 Star Trailer

Updated 04/13/2017 | Published 04/11/2017

Question:

I have no running lights on my 4 star trailer

asked by: Eamonn H

Expert Reply:

If you do not have any running lights on your trailer, I recommend first testing the trailer connector on the vehicle to rule that out as the cause. Turn the headlights on, and use a circuit tester like # PTW2993 to test the socket on the connector fed by the brown wire. If you are not getting any signal on this pin, it is possible that there is a blown fuse.

Next, make sure that the ground wire from the connector on the trailer is securely grounded to the trailer frame, and that each lamp is grounded on the frame either by an individual ground wire connected to the frame or by its mounting studs having a metal to metal contact with the trailer frame. A single bad ground connection can cause the issues you are experiencing.

Lastly, just make sure that you have a continuous circuit from the trailer connector to the lamps, with each wiring connection being secure and protected from the elements.

I have also attached a Troubleshooting Wiring article that you may find helpful.

expert reply by: Chris R