Suggestions take truck for hook up repair battery connection

to the OP,

Do you have a wire connected at stud near fuseblock under hood as needed? Does it have 12v? trace that wire to the 7 pin connector, does it have voltage? if it does, check trailer wiring (including ground), if not, check the wire between the stud under the hood and the 7 pin connector at the back of the truck.

If you don't have these skills, then you will need to find a friend that does or open your checkbook or ignore the problem.