I hope you've had this problem fixed, but here's my $.02 if not. I had the same problem last year, tried a few things at The Stoop in Moab to fix it (including yanking the trailer wiring), even brought it to Arches Repair Center in Moab (big mistake), but nothing worked & I had to deal with the issue all the way back home to Chicago. My mechanic found a short at the right front fender light. After fixing that and the damage Arches did to the fuse box, it's been fine ever since. Hope this helps...