Probably a cable break of the display?
As soon I open my display more the 90 degrees, I got a black screen. Not totally black because I can still see the content very darkly.
When I move the display to 45 degrees and back to 90 degrees it is ok again.
Anyway 90 degrees is very uncomfortable.
Is it perhaps a cable break of the power cable to the display? ...or what can it be?
How exactly can I repair it and where do a find a manual for it?
Is this a good question?