Joe, I knew you didn't mind getting dirty but this is a bit much. Have fun.

I'm replacing a watchdog and inverters right now. Always an interesting task. In this coach the entire engine control system was replaced by the watchdog. I generally don't spend too much time trying to trace the rat's nest of wires. I find it easier to simply remove everything a trace where the wires actually go. The owner said he was having a problem where the generator would only run for 30 seconds or so. I bet that explains why someone wired around the failed oil pressure safety switch.

Anyway, have fun.