Check what?
The inverter is powered from the batteries, until they are charged it won’t work.
If you were in store mode, you won’t be able to change to in use mode until the batteries get a charge (the use ,store relay operates from those batteries.
Batteries are disconnected from the converter in store mode, so even on shore power they wouldn’t charge.
Either put a charger on them or start the engine and let the alternator charge them. Until you can operate the use,store relay.
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