Getting ready to head South next week. After wintering motor home, left it plugged in and with all slides closed. When I went out today and opened the door, I could see microwave light on but nothin...
I agree, if you can start the engine and the generator....both sets of batteries are fine. Also, the microwave works off of 120vac (shore power or generator) as do the AC units, which means your inverter is supplying 120vac to the microwave.
If you don't have 12vdc, I suspect that you have inadvertently switched the salesman's switch off at the door.