I have a Canon Pro 9000 Mark II, several years old. During the last two weeks when I turn it on the orange flashing light gives 4 flashes indicating either an empty ink cartridge or one not locked in place. However, none of the cartridge lights are on. I've gone through them over and over, taking them all out and re-inserting; even tried resetting the printer; nothing works. I can't run the cleaning function either. All the cartridges have ink in them.
Any suggestions? Do the indicator lights ever just get old and have to be replaced?
