Troubleshooting Trailer Lights That Come Back on After Turning off 2001 Ford Windstar

Question:

Hi, I have a problem, when I turn off my vehicle 2001 Ford Windstar LX, in a few minutes the trailer lights will come back on without the vehicle on.

asked by: Lynn A

Expert Reply:

It sounds like a ground and/or short circuit problem. What you will want to do is disconnect the trailer from the vehicle. Use a circuit tester like # PTW2993 to test the 4-Way on the vehicle side. If the signals are all coming through like they should, then you know the problem is on the trailer side.

If the signals are not coming through correctly, the converter box could be bad. To test the converter, test the signals going into the converter from the vehicle. If those are correct going in, but coming out they are wrong, then you know the converter is bad. If the signals are wrong going into the box, then there is an issue with the vehicle wiring. You may need to check to see if a fuse is blown or a relay has gone bad that is related to the tow package wiring.

If everything checks out on the vehicle and all signs point to the trailer, start by checking the vehicle and trailer side connectors for dirt and corrosion and clean them out. Then you can make sure that the main ground for the trailer and the grounds for the lights are all connected to clean and corrosion free bare metal surfaces.

expert reply by: Chris O