Keyboard backlight stopped working

My MBP is a 2.4Ghz. The keyboard just suddenly does not light up and when I press the keyboard backlight keys I get up a symbol with at light with "not available" sign over it. Seems it is telling me that there is no backlit keyboard available. I don't think I did any damage to the MBP but of course a lot of people use this machine and could have dropped or hit it. Why does the keyboard backlight stop working and how can I fix it?

Answer this question I have this problem too

Is this a good question?

Score 0
Add a comment

4 Answers

Most Helpful Answer

You should watch all three parts of this repair, at 4:57 of Part 2 of the videos it addresses a plug that controls the backlight of the key board. if that plug was accidentally disconnected as a result of dropping it, the backlight would stop working (as it says in the video)

*Part one http://www.youtube.com/watch?v=jUonF9OSv...

*Part two http://www.youtube.com/watch?v=ty7iaWr_l...

Hope this solves it!

T.H.

Was this answer helpful?

Score 2

Comments:

Thanks for the tips. Sorry to say this did not help. I checked the cable and took it in and out. Still get the sign for no backlit keyboard connected.

by asle

Update! I downloaded the app labtick from http://labtick.proculo.de/. That turns on the keyboard backlight. So the backlight works but it is not possible to trigger it when it is dark. Seems there is some sensor not working then. Do you know where is the sensor under the topcase that triggers the backlight?

by asle

How can I check if the sensor works? Anyone know where the sensor is exactly?

by asle

asle, this is what I got. "The right ambient light sensor is part of the logic board but has a removable dust cover. The left sensor is on a circuit board mounted to the left speaker."

by oldturkey03

Add a comment

Boot to a known working Operating System, does the backlight work in here? This will help diagnose if it is a software or hardware issue. There is no point trying to repair hardware when it could be the O/S. If the backlight works in the other O/S then re-install from your OSX Installation disc.

Hope this helps,

Wes

Was this answer helpful?

Score 2
Add a comment

Did you reset the SMC yet?

See Apple tech note: http://support.apple.com/kb/HT3964

As one of the things it does get involved in is saving of the pref of your back light settings (display & keyboard)

Was this answer helpful?

Score 1

Comments:

Yes. One of the first things I tried.

by asle

Did you boot up on a clean OS install off an external HD?

by Dan

Add a comment

OK, so this is weird. Had no backlit keys, sometimes the F8, F9, and F10 keys acted like there was a backlit keyboard, but nothing lit up. Tried to install LabTick, but it said "no backlit keyboard." So in playing around, I pressed and held Shift-Alt-Command and then (still while holding) the power button. it toggles the keyboard backlight on and off! This is on a PowerBook G4 15-inch 1.67/1.5GHz. Hope this helps someone else. Docimastic

Was this answer helpful?

Score 0
Add a comment

Add your answer

asle will be eternally grateful.

View Statistics:

Past 24 Hours: 6

Past 7 Days: 43

Past 30 Days: 139

All Time: 8,365