Backlight Keyboard won't light up...

you know i have the same problem and i can't get it back either.
i was messing around with some hot keys when mine stopped lighting up lol.
i think some how we accidently locked the keys or something... i'm try to search for some answers to cuz i LOVED my backlighting u_u if you find an answer let me know.
visa versa.

i've recently fixed the problem..
i toggled settings and put them back to default ( the keyboard ones) and i put it in the dark and all the sudden the backlight came back. i was happy! and then i pushed the backlight key on my keyboard and it allowed me to brighten and dim it.

so i'm not to sure what EXACTLY fixed it but it worked!
so maybe you could try doing that.

kind of vague, but who knows.
i hope this helps someone.
cuz i know how much i like to brag about my keyboard backlight =]

Having the exact same problem here. Getting the crossed out circle.
Tried doing the Mac OS Software Update, but still the same after update and reboot.
The keyboard lights up when I use the "Lab Tick" software, but one shouldn't have to uninstall 3rd party software to fix an OS/HW bug.
***?

ok, so i was having this same problem. but i was messing around with the buttons, and i figured out that if you toggle the F1 and F2 buttons while toggling the keyboard lighting buttons, it will light up.
i was getting the same exact things. I know this is definitely a solution because i did it, and it worked, and 5 mins later, my keyboard lighting buttons didn't work, so i did it again and it worked.

just toggle the screen brightness and keyboard lighting and VIOLA 😀

Just to follow up, what was wrong with the previous one was that the built-in camera wasn't working so that they keyboard algorithm read that as "it's too bright" and refused to turn on the keyboard lighting. The USB controller was actually bad, i think as there was no Bluetooth receiver detected on the USB tree. Got a replacement and new machine works great.

the way i fixed it was to....1 shut down the computer. 2 take the battery out and remove the power cord. 3 hold in the power button for 10 seconds. 4 plug the power cord in. 5 turn the computer on. 6 place the battery back. 7 now your key back light should work...at least mine did. hope this works!

So i just ran into the same problem and found there's an easy way to check to see if you have a hardware malfunction without taking out your battery. I know this post is old so maybe this will help out someone with the new MBP.

I have the new macbook pro and the ambient light sensor is right next to the isight camera. If you are unable to illuminate your keyboard (you get the little circle with a line through it) just put your hand right in front of camera covering most of the light. Two things should happen, first your screen brightness should dim automatically and then you should be able to adjust your keyboard lights. Take your hand away and the screen will adjust itself back to a higher brightness and you once again lose the ability to illuminate the keyboard.

Hope that helps.

OK, the NEW UNIBODY MBP's wont light up the keys if its too bright out, just hold your hand over the camera (where the light sensor is) and it will light rite up, but make sure its enabled in System Preferences> Keyboard and Mouse> Keyboard Check the box that says to automatically illuminate the keyboard in low light condition. Hope this helps!!!

PS: It knows how much light there is, so until its not as bright out, its not going to let you light it up, regardless of battery power.

Message was edited by: Shurtugal1005

Message was edited by: Shurtugal1005

I just tried covering up the camera and was able to adjust the lighting but it only works with the camera covered. The keyboard illumination went out as soon as I took my hand off. I do have the box checked in system pref.

Check out LabTick http://www.macupdate.com/info.php/id/22151/lab-tick.
It lets you override your MBP's flaky light sensors....you can set your keyboard lighting to your own taste.
It's been working beautifully for me since I installed it months ago.

System Preferences>Keyboard & Mouse>Keyboard. Make sure the appropriate box is checked.

Try to toggle the checked box off and then on.