Short of taking the kb apart is there a way to determine why a cap lock key isn't working? No light no nothing just dead.😕
It is the regular apple keyboard that comes with all intel imacs.
(currently equipped to imac cd 1.83ghz)
You could just pop off the key to take a look underneath. Maybe the light is dead, the mechanism detached, or you spilled something in there. It's odd for a newer machine but it's possible. (My Pro Keyboard from 2001 is still fine).
I think you can buy the bulbs at radioshack or something pretty cheap. If the rest of your keys are fine and there is nothing apparent then I would assume it's the bulb. I'm not quite sure if a burnt bulb would stop the key from working, but maybe someone else knows more.