I am not an inverter expert but E01 and 02 are opposite battery voltage level alarms I think? So I would suggest taking your handy dandy voltmeter and measure your actual coach (house) batteries when they are not charging and unloaded if possible (wet cell are 12.6vdc full charge; 11.9 full discharged). If the inverter is giving high and low voltage alarms I would wonder if all battery connections are clean and tight. Possibly if the batteries are so low you can't get a proper sense reading for the inverter (not sure why it would error too high though). Might need to charge with a stand alone charger first to get batteries back up. Did the shop prove to you that all was working before you headed home?
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