Thanks all! I continue to diagnose.
I can't believe in all my years, I have not learned how to use a voltmeter. Yes, that sounds dumb, but I am a carpenter by trade and then management for the last 30 odd years and have always left the mechanical work on my vehicles to the professionals.
You see, I am a "Bleeder". All I have to do is look at a wrench and the skin just falls off my knuckles and the bleeding starts LOL!
If these damn RVs were made of all wood, I could fix them in my sleep!