I've chased the wires. Gray/Tan go to the loom where they are tied to yellow/green which is connected to the emergency start switch.
Red jumps from the circuit board to the BIM.
Orange goes to red in the loom, which then follows the orange/green pair. It enters the cab just behind the drivers seat in the filler on the left. At the base of this filler, there is an uplifter loom, near as I can tell. The red is spliced into a small orange in the factory loom.
I checked this lead - no voltage while the ignition is on or when the engine is running. All fuses in both the underhood panel & under drivers seat panel check ok; none are blown. (both panels are difficult to get to & the underhood one is particularly difficult to remove the covers. Be sure to remove the short one on the left, then the main one. shame on GM....)
While tearing into panels & under the floor mat, I found a ton of assembly scrap - shame on Forest River.
So, other than knowing where the wires are run to, and which wire does what, I'm no closer than I was. I have two specific issues:
1) No ignition power on the orange.
2) A jumper from chassis power to J12 shuts down the 12V branch - all goes dead until I remove the jumper. One of the small relays clicks solidly when I jumper the connections - but not the large solenoid.
I need to find a chassis schematic to see where that orange heads off to... and perhaps build up a new charging solenoid with a different brand.
However, I'll contact Precision Circuits with this info - perhaps they have suggestions on the setup. They won't know about the chassis to loom wire, but they should know the function of the orange in the BCC.
Fun.
