Troubleshooting No Running Lights on a Trailer Towed by a Ford F250

Updated 09/09/2014 | Published 09/06/2014

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Pollak Metal 7-Pole, RV-Style Trailer Socket - Vehicle End

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Hook Probe Circuit Tester

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Question:

I have a ford 250 4/4 super duty. No running lights to my 5/ wheel or my boat when pluged to the truck.

asked by: Alvin M

Expert Reply:

It sounds like the running light circuit of the trailer wiring on your Ford F250 is at fault. I would still verify this by using a circuit tester like our part # PTW2993 to check the running light pin of the trailer wiring connector.

I would then check the fuse boxes on your truck for the trailer wiring circuits and replace the fuses as necessary. There also could be corrosion in your trailer connector that is preventing the circuit from making a solid enough connection to activate your trailer's running lights.

I attached an FAQ article on troubleshooting 4-ways for you to check out as well as a video on how to test the circuits of a 4-way with a circuit tester.

expert reply by: Jameson C