Thank you to all who helped me out with my problems. Happy to report the AQH is now functioning as intended. Not exactly sure which thing I did solved the problem because it just started working. Hopefully it keeps going.
And a special thanks to Fred Brooks who helped me systematically make sense of the AC problem. We tracked the problem down to a bad comm wire between zone 3 board and the front AC. Rear AC is now functioning and we’ll be able to survive the end of TX summer as we move in to the coach to start a home renovation.
Now to chase down some 12V gremlins in the power shades. It never ends with these 26 year old coaches. Always an “adventure” as Fred reminded me!