Akai Mx-73 control board

Hi

I just picked up a mx73 that has two issues.
The lcd screen lights up but displays no text.
The buttons don’t don’t engage the leds.

I checked the voltage from the transformer and the fuse continuity, both were good.
The contrast knob on the back does nothing when rotated.

Could this be an issue with the firmware eprom?

Any help is much appreciated!