When I press the F5/F6 button, the HUD shows a decreasing/increasing bar related to the keyboard's brightness (image).
So far so good… The problem is: the keyboard stays completely dark, no light is emitted from the keyboard, even though the bar is moving when I press the keys F5 and F6.
I've already tried to reset PRAM and SMC but it didn't fix my problem. What should I do?