[jaimem]

It started today and randomly the keys on my Macbook Pro (2.0ghz, running 10.6.3) stopped working. No matter how much (or hard) you press them, nothing happens. The weirdest thing is that only keys A-L dont work. The caps lock worked as well as the semi-colon and all the other keys on my keyboard. I tried rebooting and nothing solved it. Then randomly they just started working again. It happened this morning for probably 5 minutes and just again when i got home from work, again they were only "broken" for about 5 minutes or so. I did nothing to solve the problem & magically the keys A through L began to work again. Also they are not sticky and have not come into contact with any water, etc. as far as i'm aware.

Has anyone heard of this? I haven't done anything "new" to my system recently for them to just stop working this morning at random. Also i have checked all the settings in System Preferences & all is well. I'm guessing they will stop working at any time again...its super random. Please let me know if you have any info.

[Zanziboy]

I'd try a USB keyboard to see if there is an issue with external keyboards as well. If not, it is likely that the keyboard needs to be relaxed or the keyboard ribbon is loose.

I hope this helps!

[iSilver]

I had a similar problem (only one key wouldn't work, and the problem key changed regularly, though confined to the top half of the right side of the keyboard) for a few weeks and managed to fix it yesterday .

Just for a change the "delete" key wasn't working so I pulled it off (an easy task) and discovered what looked like a little stone under the key (not exactly sure what it was because it fell on the floor as i was getting it out). I have no idea how this foreign object got in there either!

The problem key changed because the object moved around under the keyboard whenever I moved it. Once removed the keyboard is functioning correctly. Hopefully you have the same easy to fix problem.

[sudowork]

Originally Posted by iSilver 

I had a similar problem (only one key wouldn't work, and the problem key changed regularly, though confined to the top half of the right side of the keyboard) for a few weeks and managed to fix it yesterday .

Just for a change the "delete" key wasn't working so I pulled it off (an easy task) and discovered what looked like a little stone under the key (not exactly sure what it was because it fell on the floor as i was getting it out). I have no idea how this foreign object got in there either!

The problem key changed because the object moved around under the keyboard whenever I moved it. Once removed the keyboard is functioning correctly. Hopefully you have the same easy to fix problem.

Yeah, debris in the keyboard can cause the keypresses to not register. When the problematic keys change, it is very indicative of debris under the keyboard.

However, what you're describing does not seem to indicate debris under the keyboard. I would get your keyboard replaced by Apple. This seems more like a hardware issue. Every keyboard utilizes its own keyboard matrix based on the circuitry of the keyboard (at the discretion of the manufacturer). For your case, A-L may be on the same electrical path, that could be shorting.

See this page for more info:
Keyboard Matrix Help
And here's an example of a keyboard matrix. Note that it's not the one that the Apple uses:
http://www.zimmers.net/anonftp/pub/c...ual/p4-07l.gif

[P]

Read the linked docs above, but basically the lead for the horizontal line up to L is broken. Either you have Apple fix it, or you try to do it yourself with conducting ink or similar.