Q: ibook g four key stopped working

The individual key may be repaired, but then it may not. There are

parts beneath the key-face that could be dirty, sticky, or broken.

There is a flexible piece under the plastic key top and a squishy

other bit that make up the single key; it may be dirty or otherwise

only partially failed. If so, you may be able to take that one key

apart to see if cleaning it may help. There also may still be parts

for single key repairs available, such as the spring part & cap.

"Key, Hinge, Cup" are the three main parts, including key-face.

•Remove/replace a single key - note more than one model of

keyboard may have been used in your version iBook G4:

http://www.youtube.com/watch?v=g1guAmUaMxc

See link to iFixit guide -- to remove entire keyboard, below...

near the bottom. (This image is from the other web site of

the parts that may be in your keyboard, under keyfaces &

would need to be identified if you should need to order a

replacement set of individual parts under the keyface.)

See what the parts for single keys look like at this page. They can

appear different depending on when the keyboard was made. This

can help you identify the parts; be sure you actually know more

about the keyboard and their appearance, before taking it apart.

There is a click-on to see detailed instructions on how to do this

that does not require watching a video. The instructions appear

in a pop-up image if you click on the words that say:

" > Read detailed instructions for this step" -- to show this image:

.....

•Apple iBook G4 (white) Laptop Keyboard Key (detailed parts)

http://www.laptopkey.com/KeyboardKeys.php/Apple/Ibook/G4%20%28white%29

•info & video:

http://www.laptopkey.com/Guides.php/Apple/Ibook/G4%20%28white%29/A9

There should be instructions in iFixit's iBook G4 repair guide that outline

the steps to remove the entire keyboard completely, from their site...

•iBook G4 12-inch 1.33GHz - repair guide - iFixit:

https://www.ifixit.com/Guide/Device/iBook_G4_12%22_1.33_GHz

•Keyboard remove/replacement section from above iBook G4 Guide:

https://www.ifixit.com/Guide/iBook+G4+12-Inch+1.33+GHz+Keyboard+Replacement/694

Hopefully this helps somewhat!