Blackberry has blank screen but rings when someone

You can customize your BlackBerry Tour so that either it rings when you get a phone call, or it vibrates -- or both. To make your phone both ring and vibrate when you get a call, go to your BlackBerry's sounds and ring tone options, which you can get to by either of the following two ways:

#1 - Use the trackball to go to the sound icon in the upper left corner of the main screen and click on it, then toward the bottom of the list that appears, select Set Ring Tones/Alerts, then select Phone.

#2 - On the main screen, press the BlackBerry button (the one with the seven dots) to take you to your Home folder. Scroll down to the Options folder (it's usually toward the bottom, and it has a wrench icon) and click on it, then select Sounds and Ring Tones.

From this scren you can select the ring tone that you want and adjust the ring tone volume. Then scroll down to Vibration and set it for On.

There is also an option for Vibrate with Ring Tone. If you turn this option on, the phone will both ring and vibrate at the same time when you get a call. If you turn it off, the phone will vibrate first, then ring. Either way, you'll get the ring and the vibration -- it's just a matter of whether they happen together or not. To see the difference between the two options, use the "Try it" option at the bottom of the screen.

When you've made the selections that you want, exit out of the options screen, but be sure to choose Save rather than Discard to save your changes.