The curve has to be in a dark enough spot to light up. There is a light sensor that the blackberry measures light, if it's dark enough then it will turn on the keypad.
This is a really nice feature since it actually helps to use less of your battery for the backlight since we all know if you have the backlight on all the time it runs the battery down fast.
I'm kind of experiencing the same problem. I have the 8310 curve and recently just upgraded to the latest v4.5 OS three days ago. After reconfiguring all my settings and restoring all my data after the upgrade, I noticed that my keyboard/trackball were not lighting up. My settings were set to 100% brightness and "automatically dim backlight" was turned OFF. I called my service provider's tech support and now they are sending me a new device. The tech said it might have been just a "faulty hardware device"
But this didn't happen before I did the OS upgrade. And I'm finding time to time when the backlight is suppose to be on, its not. And then suddenly it works.
Can anyone explain this? And also tell me where the light sensor thing is located on the curve?
Posted from my CrackBerry at wapforums.crackberry.com
