Brightness keys F4 and F5 not working on Dell XPS 15.6 Laptop

Question

Please provide me a solution how to fix this?

@SirCharlo A laptop's backlight is not controlled by the graphics card or graphics drivers.

SirCharlo · Accepted Answer · 2012-05-25 13:07:28Z

Edit "/etc/default/grub" as root.

gksu gedit /etc/default/grub

Now, look for the line that looks like:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash"

Append "acpi_backlight=vendor acpi_osi=Linux" to the end of that line, before the end quotes, so that the line now looks something like this:

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_backlight=vendor acpi_osi=Linux"

Save and close the file, and run the following command:

sudo update-grub

Now, reboot, and test out the brightness keys. They should be working correctly now.

Timo · Answer 2 · 2012-05-25 11:44:46Z

up vote 0 down vote

It's for the XPS 17, but maybe it works on the 15" model too.

answered May 25 '12 at 11:44

Timo
2,3091215

I didnt check ur solution,because the above one worked....still anyways thanks for the effort :) – Rahul May 28 '12 at 11:05

2 Answers