Ответ на "iPhone 4 screen is black after replacement"So after trying the 2 LCD's that didnt work. I decided to cut my losses and just throw the old broken LCD back in and sell it on eBay as a broken device for parts and just report the problems that it was having. To my amazement it fired right up with no display problems at all. I guess it was just an extremely unlikely coincidence that I had two screens that were duds in a row, (I've done 40+ screen replacements and these were the only duds I've ever encountered.) I know that I'm not the first person to mention this in this thread, but if you are having this problem I would highly suggest trying the original LCD back in it just to see if you have a bad screen.