What is the best way to prevent corrosion on boat trailer lights and wiring?

[bruceb58]

I believe I used that very same 7 pin harness with the junction box. The one I had was wired wrong. I had to move almost all the wires around to get it properly wired. But it was definitely handy for terminating everything in one neat spot.

I have used 3 of these. All were correct as far as color coding. It's just a junction box...you connect the correct wire on your trailer to the corresponding wire coming from the connector. What am I missing here?

 

[JASinIL2006]

The confusion can come in because not all plugs are wired the same...