Disconnect the remote from the inverter.
Wait ten minutes with the power off to the inverter.
Now manually turn ON the inverter without the batteries connected.
Finally reconnect the remote, manually turn the inverter off, and restore battery power.
Turn the inverter back on, but first, cross your fingers, and pray to the inverter Gods.
If the Magnum is not under warranty and you truly need auto start generator, move to Victron.
Regards, Don
My ride is a 28 foot Class C, 256 watts solar, 556 amp-hours of Telcom jars, 3000 watt Magnum hybrid inverter, Sola Basic Autoformer, Microair Easy Start.