Good to be here. I replaced the screen of my Thinkpad edge 13, after it suffered for more than 6 month from the well-known central vertical lines-problem...
With the new screen, the brightness control via FN-F7/F8 stopped working.
Even manually it's not possible to set the brightness.
where max_brightness equals 4422465 (!) for the first and 15 for the second.
FN-F7/F8 writes to thinkpad_screen/brightness, but also echo'ing numbers from the interval [0 - 4422465] to intel_backlight/brightness can only turn on and off the backlight, but not dim it.
and ran update-grub. Didn't help.
Do you have some ideas how I could rule out hardware problems?
Would be great to get some pieces of advice!