I had the same problem with a laptop a couple of years ago. I actually pin pointed the problem down to a wire. A wire that feeds into the screen was getting pinched slightly and it was causing the backlight not to work. If you are inclined to try, I would carefully take it apart and check for any pinched or crimped wire(s).

 

I agree, it's likely a wire breaking down when it moves due to the main lid assembly moving. I'd imagine it is being pinched when the display assembly moves, but it could need the wire wire replacing.

 

Hey guys, just replaced the big LCD cable that goes from the top of the LCD down the board and all seems well again so I think you were both spot on. I assume the cable has just given up after 5 years of the lid being opened and closed on it.

 

I'd say your bang on the money with that assessment. The cable was probably rubbing in a certain spot against the laptop chassis or against itself on a tight bend (or both) and fatigue eventually caused it to break under certain circumstances.

Glad to hear it solved your problem and thank you for letting us know everything is resolved. It's nice to hear happy endings.