Kevin has a point of sale touch screen system and it blacked out right in the middle of sale and didn't come back. What can he do? Leo says that when a screen goes out, it could sometimes be the backlight. If he looks at an angle, he may see a very dim screen. But if it's totally black, that means that the screen completely died. Or it may be a bad cable. Leo suggestions changing out the cable to start. If it's proprietary hardware and software, then it's not going to be user repairable.