Keyboard Light

Hi Benjamin,

Have you tried resetting the PMU?

http://docs.info.apple.com/article.html?artnum=14449

Jrsy

Well given your previously stated issue along with the status light being 'always on' I'd say there may be some malfunction going on with the logicboard. If you have AppleCare or the PBV is less than a year old I would consider contacting Apple or taking it to a Apple store for service. Good luck!

Jrsy

please update on your problem. i recently have found that i had the exact same symptoms. thanks.

Hi

The keyboard backlight not working and the option to turn it on or off not appearing in the keyboard and mouse control panel will be due to either a hardware or software problem. There have been a number of threads to do with this in these discussions, so you may want to search through them.

First up you should try resetting the PRAM and the PMU.
Here are the instructions for the PRAM
http://docs.info.apple.com/article.html?artnum=2238
Here are the instructions for the PMU
http://docs.info.apple.com/article.html?artnum=14449#faq10

If that does not work you can try creating a new user account then log-in to that account and see if the backlight works.
Next try deleting the following files:
Macintosh HD>Library>Preferences>com.apple.BezelServices.plist
And
Macintosh HD>User>Library>Preferences>com.apple.BezelServices.plist
Drag both to the trash and then restart, these files are preference files and you cannot delete them until they are 'not in use'. So to do this you need to restart, the system will then regenerate new files and you can then delete the old ones.
Check your keyboard backlight is there a check box in the keyboard and mouse control panel?
If it is still not functioning we are running out of options.
I would hazard a guess if you try all the above and still there is no option to turn on the keyboard backlight by the checkbox in the Keyboard and Mouse control panel then it is probably a hardware failiure and you need to contact AppleCare if you have it and see about getting it fixed. Some might argue trying an Archive and Install of the System in case some piece of software has got corrupted or gone missing. That's up to you.
All the best.
Phil

"Check your keyboard backlight is there a check box in the keyboard and mouse control panel?"
i downloaded the stand alone 10.4.6 update again and now that box isnt even there!

and my stupid sleep light is slowly bliiiiiiiiiiinking, bliiiiiiiiiiiiinking...
irritating. plus my startup noise never works (and yes i have tried eeeeeeverything for that)..
i have reset the pram many times and it never helps. i took it to the apple store and the genius said if i need to have it repaired it might take a week. right now i cant part with it until i back up some stuff and finish some webdesign.
guess ill try those playlists. thats the only thing i havent tried...
thx.
ps: how do you figure out what model your powerbook is? i saw this

PowerBook 100
PowerBook 140, 145, 145 B and 170
PowerBook 150
PowerBook 160, 165, or 180
PowerBook 500 series
PowerBook 200 and 2300 Series
PowerBook 190, 1400, 2400, 3400, and 5300 Series

on the PMU article but i dont know which one i am.
thx again

ps: how do you figure out what model your powerbook
is? i saw this

PowerBook 100
PowerBook 140, 145, 145 B and 170
PowerBook 150
PowerBook 160, 165, or 180
PowerBook 500 series
PowerBook 200 and 2300 Series
PowerBook 190, 1400, 2400, 3400, and 5300 Series

on the PMU article but i dont know which one i am.
thx again

I presume from your statement:
My Powerbook 1.67ghz 15" has a problem with the backlight for the keyboard. I seem to have lost the function.

That your PB is a 1.67Ghz model therefore the instuctions are these:

PowerBook G4 (15-inch 1.67/1.5GHz), PowerBook G4 (17-inch 1.67GHz), PowerBook G4 (15-inch Double-Layer SD) and PowerBook G4 (17-inch Double-Layer SD)

1. If the computer is on, turn it off.
2. Disconnect the AC Adapter and remove the computer's battery.
3. Press and hold down the power button for 5 seconds and then release the button.
4. Reconnect the battery and AC Adapter.
5. Press the Power button to restart the computer.

Regards

Phil

My keyboard illumination is also failing, but only after sleeping the computer. It works fine after a reboot, but will not work after waking up from sleep. After that, it does not illuminate the keyboard no matter how dark the room and if I use the brightness adjustment function keys I get the "it's too bright" action-prohibited symbol in the on-screen graphic, even in total darkness.

The display brightness continues to work, automatically adjusting to room darkness/light and responding to those adjustment keys, although it may be somewhat less responsive to ambient light.

This is perfectly reproducible; at least 5 out of 5 restarts restored the functionality but it failed again after sleeping and waking.

I have a PowerBook G4 1.33GHz, running 10.4.8. I've reset the PRAM and the PMU (which was interesting) and trashed the com.apple.BezelServices.plist files both in my account and the global one in /Library/Preferences and then restarted. I've tried using a different, default-settings account.

I do know that it won't work when the room is too bright, and I'm sure that the checkbox that enables the functionality is checked in the Keyboard & Mouse preference panel. Remember it always works fine after a restart.

Is anyone else seeing these symptoms? This is the only apparent flaw in my PowerBook's functionality, and I use practically every hardware feature it has fairly often. It just doesn't seem to be a corrupted Mac OS X, but you never know.

PowerBook 17" 1.33GHz Mac OS X (10.4.8)

Had the exact same issue. It wasn't a major deal but it bugged me. My ram slot died and I sent the laptop in for repair and mentioned the keyboard situation to the tech. He said the connector from the sensors to the logic board were loose and he repaired them - now it is PERFECT!