Oki es3640 MFP Inverter error

I have an es3640 that we've had in storage for a few years. I need to use it again but when I hook it up I'm getting an error that the inverter is not connected. From what I can find the inverter is built into the finisher which I've checked and it has power and the serial connection from the finisher is hooked to the printer.

It does give me an error 474 when I press help during the error.

Thanks in advance.

Edit: Aaand i did a factory reset and it thinks its a C9800 :(