Ubuntu – Asus UX303LA fn brightness keys not working

function keys

I've searched everywhere for a solution.

I've tried this:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash pcie_aspm=force acpi_backlight=vendor acpi_osi="

each variable on it's own and different combinations. Also acpi_osi=Linux

In all of them fn+f5 and fn+f6 (for brighness) fn+f2 (for airplane mode) doesn't work. They don't even register in acpi_listen or xev.

Best Answer

Since those keys don't have acpi functionality, you can set the function manually through ccsm using xbacklight commands.

Run the following commands:

sudo apt-get update
sudo apt-get install compizconfig-settings-manager xbacklight
  • Now, press ALT + F2, type ccsm, and then press ENTER.

  • Next, enable the commands plugin and then click on the commands plugin.

  • Enter the command command line 0.

  • Click on the key bindings tab and click disabled on the command line 0 row.

  • Check the enabled box, click grab key combination and then press the key combo you would like to use to increase the brightness (fn + F6 for example). Click okay.

  • Finally, do the same for "command line 1" to set the brightness decrease except use the command xbacklight -dec 10 and use a different key combo (of course).

Thanks to this answer here provided by @TejasGhalsasi


You can set similar keyboard combos for other functions. The command to turn off wifi is:

nmcli r wifi off

and the command to turn wifi back on is:

nmcli r wifi on