With the coach plugged into shore power what voltage do you have at the batteries? Is the Converter breaker tripped. The voltage you saw after a 7 mile drive is surface charge, the batteries didn't have enough time to charge.
With the alternator a dead battery, and 9+ volts is dead, will take several hours to charge and it might not hold the charge.
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2016 Axis 24.1 E-450 6 spd tranny
300 watts portable solar.
200 watts solar on the roof.
Wrangler JK dinghy
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