i have a Motorola phone. i forgot the name but it's the slide phone with the full keyboard and the part touch screen. The screen went totally blank, it's all black. I tries turning it on and off, i put it in the freezer for a couple of minutes, i took the batteries out sometimes, and i tried banging it over and over again but it still didn't work. this already happen once but the next day it went on again and I'm not sure how. HELP!