the joys of old hardware
I've read this too but I get the error with no drive attached so don't think a Filesystem is causing the issue
From experience this seems to be a scsi chip problem, I have the same thing with a GVP HC8 II for an A2000, most cards use AMD scsi controllers and these are very sensitive for incorrect power on the lines, certainly placing your scsi cable in the wrong direction.
You might wanna try disabling the scsi or autoboot, see if the card just starts on it's own.
If you have another scsi controller like an A2091, that would allow you to boot.
If that works, you know what to do, find a replacement chip, and the have a professional do the soldering or if you are an expert yourself.