I had to change a busted light on my utility trailer the other night after I backed it into a tree stump,Censored Don't ask long story. Problem is after I swapped out the light I didn't have any running lights on the trailer, park lights on the truck were working fine. Checked the fuses in the panel on the drivers side of the dash, no bad fuses. I then rechecked the trailer no problems there. hooked up to the camper and horse trailer same thing, brakes and turn signals but no running lights. Anyone have an idea where I need to check next. I'm sure I blew a fuse but I can't find it is there another fuse box under the hood maybe. The rest of the trucks lights a working fine. Any help to avoid a trip to the dealer would be great.

Make sure you didn't fry any wires around the trailer plug in on the rear bumper. I had that happen once.

Yes, there is another fuse box under the hood. Big black square thing over the front driver's side wheel. Like you said, it is probably a fuse.

I have the exact same problem and it has been doing it since day one. There is another thread where this is being discussed.

Are you sure the lights were ever working right in the first place? Mine weren't.

I had to change a busted light on my utility trailer the other night after I backed it into a tree stump,Censored Don't ask long story. Problem is after I swapped out the light I didn't have any running lights on the trailer, park lights on the truck were working fine. Checked the fuses in the panel on the drivers side of the dash, no bad fuses. I then rechecked the trailer no problems there. hooked up to the camper and horse trailer same thing, brakes and turn signals but no running lights. Anyone have an idea where I need to check next. I'm sure I blew a fuse but I can't find it is there another fuse box under the hood maybe. The rest of the trucks lights a working fine. Any help to avoid a trip to the dealer would be great.

Did you locate the fuse? And was that the problem?

TRL PARK, Fuse 15 A, Fuse Block - Underhood.

Straight - Line from fuse to connector.

Good Luck.

Idahofox

Here's a pix of where the fuse goes in the fuse block. This fuse has gone on me a few different times now, seems to happen when the lights are turned on on the truck. Now I turn them off when I plug the connector in and so far haven't blown the fuse.

Take a 12 Volt Test light and check all of the pins on your connector. This way you will know which way to trouble shoot. Either back to the tow vehicle or the trailer wiring. Probably a fuse but I have had loose connections cause the same situation..Jim