Hey guess I just realized what is causing my fuse to blow which powers the reverse lights and cup holder lights. I posted a while back about this but was unable to fix it because I wasn't sure what was causing it. BUT I have figured it out. I put one of those 4 flat wiring kits on my truck and u know how they plug into your taillamp? Well Thats what mine is and everytime I hook up any trailer, doesnt matter which one, just any trailer to the 4 flat it blows that fuse. Does anyone know why it is doing this? Do I have something backwards? Has anyone ever had this problem before? Thanks

 

Sounds to me like something is backwards. Verify that the ground connections on the plugs are connected where they should be. I suspect that when you hook up the trailer that one of the wires is that should be feeding the lights is going to ground.
Let us know how you fixed the problem.

 

I had the same problem with my 2000' 1500 PU it was a bad connector from the factory.
TRy a new one I am sure that will fix your problem!
I had mine installed from a dealer and he warrantied it.

 

what connection is bad from the factory? The 4 flat that I boguht from autozone?

 

I can't picture why it blows the reverse fuse unless you hooked it up to the wrong bulb. On a flat 4 wire connector white is ground, brown is running lights, yellow is left turn, green is right turn. Make sure you ground the white GOOD and make sure the trailer has the white wire grouned on it 90% of the time its a bad ground.

 

There was a faulty connector in the harness TEE