Grab your multimeter and test the battery with the Coach off, should be in the 12.5V +. Then start the Coach and test the alternator with the accessories OFF in the coach, you should see voltage in the low to mid 14’s. Then test the batteries, the voltage should be very close. Next turn ON all the accessories, radio, blower, lights etc, the voltage should only drop a few tenths of a volt. You should still see high 13’s to low 14’s.
People sleep peacefully in their beds at night only because rough men stand ready to do violence on their behalf.