I'm doing some rewiring of the wires to my Lance camper plug in the truck bed and need
some help in figuring out a what a couple of wires are for. They were installed by the
Lance dealer on my 2002 Dually.

There is an RV solenoid which prevents the camper batteries from draining the truck batteries.
From that solenoid, there is a fused (20 amp) brown wire that is spliced into a yellow harness
wire that goes into the firewall.

1. What is the yellow harness wire?
2. Why is the RV solenoid hooked up to it?

http://img122.imageshack.us/img122/7930/wirepx1.jpg
http://img122.imageshack.us/img122/1862/wire2kj9.jpg

Just a guess, but is the Yellow wire hot when the Ignition is on? If so, it would be to energize the Solenoid to charge the Camper Battery when the engine is running and to disconnect it when the engine is off there by isolating the Camper Battery and preventing it from draining the truck batteries.

Sounds right to me. Cut the crappy connector out and solder that connection. Those things are junk...IMHO

i agree, thats whats called a scotch lock, not to be confused with a "T" tap, cut it out and at least use a butt connector and some tape, do the same with any scotch locks you see, they will cause nothing but problems.

and as said above solder and tape or heat shrink would be better for under the hood