Repairing an DEC LA424 Printer

I've inherited an LA424-A2 printer that had been stored for a while but now has obvious problems. Powering up 'jogs' the paper feed motor, flashes the three green LEDS on the panel through a rapid sequence, but then it stops with the display showing what appears to be a fault code. Unfortunately, one of the other parts that is failing is the LCD (16 char I think) that should be showing a fault code. It appears to be "CO <something>" but I can barely make out the "CO". Is this LCD use a traditional byte-wide interface and can it be replaced with one of the current crop of cheap LCD modules? Once I can see the fault code, I can begin to determine what else is failing, though the manual doesn't seem to be much help on error codes: they seem to be simple state-of-operation codes. Thanks, Gary