Yep that orange wire is a dedicated 12v
line that runs from the rear hatch (electrical circuit breaker area under the bath bench) along the street side up to the overhead bin on the front then over the window down to the scare light. In total it is the power or positive side of the circuit powering the 12v
outlets next to the bath mirror, the one next to the TV antenna on the street side, the radio in the overhead and the scare light. It would allow those things to work directly from the battery. The outlets were grounded individually to the trailer body. The orange cover is a pain to remove if you need to but overall it should be in great shape to reuse.