Chosen Solution
I have just replaced the screen. Everything works OK now except the backlight. I have completed a hard reset which did not resolve the problem. I have also reseated and cleaned the screen contacts which did not resolve the problem. Which contact strip is the one that controls the backlight?
It could be diode problem. you just blow it.
to rule out the backlight use the original screen to see if it still lights. the backlight circuit is not in a strip and would require microsoldering repair.
