How can I tell if the LCD card has broken on a phone before the screen starts turning black?

[AC Question]

How can i tell if the LCD card has broken on a phone before the screen starts turning black?

hi. My phone fell on the floor and everything seems to be fine but im worried that maybe the LCD screen has cracked and will start showing a black screen after a few hours. How can i tell if the LCD card has broken before the screen starts turning black?

 

[Rukbat]

You can't. If it hasn't broken badly enough to turn black, there are no electrical indications that it will in the future. (You could disassemble the 4 or 5 layers of the screen and check them under a microscope, but this is a destructive process - once you do that, the screen is garbage.)