If you get a white Blackberry screen with an error code or your Blackberry shows the red LED light but won't come on, then here's a guide on how to fix a crashed Blackberry OS . If on the other hand, your Blackberry is totally dead and doesn't even show the red LED light after connecting to a power source or PC for over 3 hours then its probably the CMOS on the board that needs to be cleared.
We would usually recommend that you leave the battery out for 24-48 hours but this doesn't work for everybody. If you have ANY hardware experience when it comes to computers you will know that sometimes you need to remove the little battery on the motherboard and then put it back to fix problems you may run into when adding new hardware, tweaking settings, power failure, etc. This does NOT mean your phone is completely dead, does NOT mean you need a new battery/charger, does NOT mean you need to reload your OS. This a hardware fault that happens when the battery is completely drained, it causes the whole board to act "dead". This tutorial fixes this issue if there is no other indications of hardware malfunctions such as broken USB port.
The battery is a small round silver looking object. It's located on the backside of the bold. This process takes pretty much NO tools, no taking apart your phone, nothing that extreme. It's actually relatively simple if you have steady hands.
1. There is a sticker covering these components that says the model of the phone, IMEI, and other information. Peel this off.
2. You will now see the small circular battery just to the right of your SIM card slot. GENTLY pry the metal rectangle that is on top of it holding it into place back a bit, until the battery will move. This will take a little bit of time, and you DO need patience when doing this.
3. When you get the battery out, put it back and make sure you put the metal rectangular piece back onto the battery and make sure it is securely in place.
4. Re-apply the sticker after you have completed steps 1-3 and put it on the charger without the battery inserted.
5. The red LED should shine again, and if you leave it connected it will show a dead battery symbol. At this point reinsert your battery & leave it on the charger! It can take anywhere from 5-20 minutes to charge up enough to boot the OS.