We have a 2007 expedition el. I got the tow package because I tow with it. I have three trailers that I tow with the truck. The small trailer and boat trailer use a 4 pin plug. My tandem axle trailer I use to haul my IH scout 4x4 uses a 7 pin trailer. I noticed my lights were not working on the big trailer and I was not getting power to the turn signals and brake lights on the 7 pin plug on the truck. I get power for running lights. In any event I look at the fuses and find a blown 25 amp fuse that controls the turn/brake lights on the 7 pin plug. I am going to replace the fuse and see what happens but any ideas on what could cause the fuse to blow would help a lot. Do you all think I have a problem with the trailer wiring? If so is it a ground problem. I need some help. BTW I do not have a brake controller yet hooked up.