I am installing a trailer brake controller on my 2007 Hurricane Four Winds 34B as well as a 7-pin trailer electrical connection.
At the rear of the RV, near the hitch, there is a 7-pin chassis harness. This harness connects to another harness which splits into four separate harnesses:
1. LR Trail lights
2. RR Tail Lights
3. License plate lights
4. 4-pin trailer wire connection.
In addition to the 7-pin chassis harness, there is also a single blue wire that is part of the overall bundle of wires but uses a separate connection.
I intend to determine if I can repurpose the current 4-pin trailer wires/connections, if the other necessary wires for a 7-pin trailer connection are already present at the rear of the chassis.
What is the purpose/function of each of the wires in the 7-pin chassis harness?