Perhaps I am overlooking something. but I don't think i am. When I pull my battery and put it back in - the BB restarts and my keyboard and track ball light up. But, they never light up again. Do I have a setting wrong somewhere? Or might I need to do a hard reset?
A battery pull will usually solve quirky little problems like that. If that doesn't help, then maybe it is the sensor. I don't think there are any other settings that control that.