I know this is a known bug, it been asked and answered thousands of times before. I've spent the past couple of months searching for a solution and all have failed.

My Fn keys won't adjust brightness and if I go to system setting > Brightness and Lock the brightness bar seems to appear for a split second then disappears.

echo 5 > /sys/class/backlight/acpi_video0/brightness

changes the value of the brightness but the brightness does not actually change.

I'm using ubuntu 12.04 lts on a toshiba satellite C50D

1 Answer 1


This is not a full solution but installing indicator-brightness is a nice workaround that worked for me on Ubuntu 14.04, but I suspect it should work on 12.04 as well.

enter image description here

Here is another page about it. All that's needed is to type these commands in a terminal window:

sudo add-apt-repository ppa:indicator-brightness/ppa

sudo apt-get update && sudo apt-get install indicator-brightness

After rebooting it should then appear as shown in the picture above. Otherwise search and launch the application manually.

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