I believe, if it's like mine, that the problem is a severed wiring harness to the display at the upper right corner of the computer case. I have the same issue and this computer is known for an issue of a bad hinge. I knew, and perhaps you felt it too, the a slight "crunch" in the area of the hinge every time I opened and shut the lid was that it was gnawing on the wiring and sure enough, in time, the screen went blank similar to yours? I'm looking for a way to replace the wiring harness but not much success. I've found the part for as cheap as $15 but no instruction as for replacement. If you find this may be your issue and come upon instructions, please let me know.
carartone@gmail.com