Trailer Running Light Fuse Location on a 2012 Ford F-250

Updated 03/20/2020 | Published 08/24/2017

Question:

Hi, I have a 2012 Ford F250 with a 7-way connector in the bed of the truck as well as the factory installed 7-way. I purchased a Pollak 7-Pole, RV-Style Trailer Connector Socket w/ Wiring Harness and Mounting Bracket in 2012/13. I purchased the Pollak Harness from eTrailer. Just recently I discovered that the running lights on the 5th wheel do not light up when I am plugged in the Pollak 7 way located in the bed of the truck, however the brake and turn signal lights work just fine. I unplugged the Pollack harness from where it plugs into the Ford factory installed 7-way. I then plugged in the Ford factory plug into the Ford factory 7 way to see if when I connected the trailer to the 7-way if I would still have problems with the running lights. In fact, the running lights still do not work, however the brake and turn signals work just fine. I believe now the problem is with a possible fuse. Can you show me via pictures or in a description where I could locate the fuses that provide the power for the 7-way connectors? Any other thoughts are most welcome.

asked by: Doug D

Expert Reply:

On your 2012 Ford F-250 power distribution box, under the hood, the trailer running light circuit fuse is in location 26 and is labeled as Trailer tow park lamps. The relay for this circuit is location 29. To test a relay the easiest way is to use a known good relay in its place. I was able to find this information in the owner's manual starting on page 321.

You may also want to check where the trailer connectors plug into the vehicle wiring harness and to each other as well as the 7-Way pins. Any corrosion can cause the lights to not work or work intermittently.

expert reply by: Michael H