First off, I'm new as of yesterday to Linux, so I'm lacking specific knowledge...
I installed Ubuntu 12.10 using an external monitor as the backlight was not working on the laptop.
Then, I installed mesa-utils which changed the graphics status from unknown to: Mobile Intel® GM45 Express Chipset x86/MMX/SSE2
Still without a fix, I tried:
which finally turned the laptops backlight on, though only each time I run it.
echo 65 | sudo tee /sys/class/backlight/intel_backlight/brightness
On the same post I found this code, it said to edit grub.cfg to:
which I did, but nothing changed after I updated grub and rebooted.
GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" acpi_backlight=vendor
I'm looking for a way to make the backlight always be on, rather than having to type the first set of code into the terminal every time, but I'm too much of a noob to know how to do this...
Additional: My fn key doesn't work (hardware problem) so I can't control brightness this way.
-- Fix --
Follow this guide: http://www.youtube.com/watch?v=0OE-Oez1NCw
replace "lampp" with whatever you decide to name the script, and replace the 2nd line (after using nano) with the first code mentioned in this post. Then reboot to check it worked.