On this vintage of equipment it’s almost always the backlight. See if you can see a faint image if you use a very bright light on it. If you can, you can probab

On this vintage of equipment it’s almost always the backlight. See if you can see a faint image if you use a very bright light on it. If you can, you can probably replace the cfl tube with a led strip. Also these displays are still available, but usually come with driver ic’s blobbed on. You can probably just bypass the blob or even mount the lcd module on the old board. (They usually just are mechanically attached ). Buy a couple of cheap character displays of the same size to practice tearing them apart. You should be able to find them around 5 dollars for the 2 line displays.