Okay, a couple thoughts to let you check for what you have done to see if it makes any sense?
This communications stuff is harder than it looks so I may not be getting the right ideas of what you are testing and how??
When looking at RV switches, it is sometimes "different" like a lot of things on RV.
The switch may not have battery and ground to it but may just pass battery through!
My main hangup on the voltage going to zero is that means you are connecting some ground to totally wipe out the 12V and that really should blow a fuse or breaker! Kind of hard to connect 12V to ground without noticing "something" happen!
I don't want to hammer a dead idea but that little bitty micro switch sized thing is one that a lot of people missed seeing as it is tiny and mounted to the bottom/back inside of the box and under lots of wires. I agree it seems like they were really putting too much stuff in one box!
That can set us up to make a mistake if we are looking at a switch using one line as ground and the other as battery! When we then switch it on, the voltage appears to go zero but it is not that it dropped but the two points we were testing are both the same voltage and that means no difference to read on the meter?
Reading with one probe on ground like the frame, etc. and seeing voltage go down gets a different thing?
But that's where I don't know how and where you were putting the probes when the voltage seemed to go down? One of those little tricky things that might snag us if we are used to the way other stuff is wired and wanted to mention it???
On motorized there is a code stamped on the small wires. Is it the same on trailers? Don't know but I'll pass this idea along---just in case?
Then if we find a code, we can use this chart to find the "from" and "to" of that wire:
https://www.winnebago.com/Files/File...ical_guide.pdf
Sorry but I'm still hung on finding that tiny little breaker hiding in the box as so many have had trouble spotting it!
Linear Mode
