Troubleshooting Trailer Running Light Wiring on 1998 Dutchmen Duck

Published 09/29/2017

Question:

Just got used camper they changed the square 6 Plug to round 7 turn signals and brake lights work but the running lights will not work

asked by: John

Expert Reply:

Often times when one function like the running lights don't work, it is due to a bad ground, a blown fuse, or a short in the wire. I recommend you start with the ground and make sure your connection on your vehicle side and the camper side are both bare metal to metal without corrosion. Then I recommend cleaning the trailer connection points to confirm good power transfer without issue.

If that doesn't solve the problem, then I recommend using a circuit tester like # PTW2993 to test each function of your 7-way. If the running light function does not work at the back of your vehicle, then check the fuses by looking for their location in your owners manual. If they are good, test the wires for function and locate the short. Replace the wire as needed. If it checks out on your vehicle side, then trace the wires on your trailer checking for function. Make sure there isn't a separate ground at your trailer lights and if there is make sure that ground is bare metal as well. Test wire for function and replace wire where a short is found.

expert reply by: Jason S