OK, I've seen some posts about this... and a few minutes ago I noticed that my MBA's keyboard was not lighting up as it's supposed to. A little experimenting and I found the solution (you may kick yourself, this is so simple):
The F5 key decreases keyboard brightness.
The F6 key increases keyboard brightness.
The icons on these two keys are the clue. 🙂
The F5 key decreases keyboard brightness.
The F6 key increases keyboard brightness.
The icons on these two keys are the clue. 🙂