Are there any alarms on the display, ie No power module then alarm number 703 ?
I would suspect if the unit is already on bypass due to fault, then I would remove and re-seat the power module in the frame and see if any better. Try to restart the Inverter after re-seating the PM
When i connected to AC source, yes its on bypass mode. i try to remove and reinstall the power module several time but still it detect NO Power Module. I suspect might be the controller board had a problem. But i cant isolate the controller board coz i dont have a spare.