I had the same problem with keys not lighting up - and the solution was the same as Jonny found - cable not plugged in. This saved me from lots of frustration when I discovered the issue late on Christmas Eve. Anyone who knows how to operate a screwdriver can do the same - of course be careful as you open it up. It only requires 8 screws to be undone - the ones directly behind the panel that is being shown removed in the video. It takes less than 5 minutes and saves a trip to the store to return it - or in my case - several days to receive a new one int the mail. thanks Jonny!
