Hello,

I have a 2004 F-150 Super Crew Larriet with the tow package. I just bought a new 12' enclosed cargo trailer. Everything works great except the interior lights. The trailer salesman said I just need a fuse. I checked the owners manual and the fuse box and all fuses appear to be in place and not blown. Again everything else works fine, the trailer brakes, the exterior lights and signals. A meter was put on the trailer so I know that the lights will work if I can figure out how to get the truck to send the power. Does anyone know what fuse would fix this?

Thanks

 

Check to see if the "trailer bat charge" relay is installed in the fuse box on the passanger side kick panel. It needs to be installed to supply 12 volts to the 7 pin connector on the bumper. This will only work when the key is in the run position on the truck, this way the truck battery will not be drained trying to charge a trailers battery while sitting with the ignition off. I'm sure that you could run a jumper wire with a fuse to supply constant power to the plug, but as said above, if you leave your dome light in the trailer on you will come back to a dead truck battery if it is sitting for any length of time.

The relay is usually supplied with the trailer brake pigtail in the glovebox, if it is not there I can't recall the part number right now. I found it using the search on here and took that number to Advance auto Parts and cross-referenced the number so I didnt have to pay Fords price.

 

Thanks, I will check it out first chance I get and let you know how I made out.