fuse keeps shorting out

[ricoboxing]

Okay heres my problem.I installed a trailer hitch and a wiring harness that I bought from Curt The fuse that is connected to the wiring harness keeps blowing. Everything else works fine. I know that it can't be caused from my trailer lights, because the fuse blows even when I'm not connected to the trailer.The harness is pretty fool proof. I checked the grounding and it is grounded in the right spot. I can't figure out why it keeps blowing.Any Ideas?

[Baltovibe]

There's has to be a short somewhere, hopefully not in that enclosed box. If you cannot figure it out, you may have to return that one for a replacement.I ordered the T-One last week; hasn't arrived yet.