Since I purchased the coach batteries from Interstate last summer and they are only about a mile from me I took the coach to them to check the batteries. Batteries now fully charged. Some symptoms have been eliminated. Here is what is left.
1. No 12 volt power when on batteries.
2. 12 volt power available when on shore power and when on generator.
3. Charging current of around 13 volts present at converter output terminal when on shore power and when on genertor power, but not showing up at the batteries.
4. Charging current of over 12 volts present at coach batteries when engine is running.
Could it be the battery disconnect solenoid?