
The top wire is the trailer backup wire, the bottom one was the one going to the aux lamps.
Now they're connected with a waterproof butt splice connector, from West Marine. These things are great - you crimp them and then heat them up (a propane torch on low works well) and the adhesive melts and fuses everything together for a completely waterproof splice. They're pricey at almost $5 for 3 of them, but to waterproof a connection, they're worth it.
http://www.westmarine.com/webapp/wcs/st ... Qgodh0YAzA
I also used them for extending a wire antenna outside - it's critical that the connection not oxidize or corrode or it affects the transmitter, so these things are excellent for that too.