So I got this back-lit keyboard that используй scroll lock to toggle the lights. The problem was that it didn't work.
My problem was that I использовал gnome туз my desktop.
Solution:
gsettings set org.gnome.settings-daemon.plugins.keyboard active false
xmodmap -e 'add mod3 = Scroll_Lock'
If you want it to work automatically, enter the command upon startup. I used System > Preferences > Startup Applications
and add the command from #2 here.
Cheers.