Answer to: iPhone 4 screen is black after replacementI had the same problem. This is how I fixed it. Remove the LCD cables, Place some windex on a napkin, wipe the connectors. There might be some windex left on the connectors, so get a dry napkin and dry off. Make sure you put back the conncetors correctly and it should work. It did for me. I only removed the battery to avoid a short circuit. and the plate that covers the LCD connector so you dont have to tear the whole thing apart. GOOD LUCK. Hope this helps some of you.