Chosen Solution
I offered a friend to fix his phone 5S but I screwed up everything. I have repaired few iphones before (only lcd replacement) with no problem, but now I failed. I swaped the cracked LCD with the new one. Moved the home button and proximity sensor cables too. Before I put back every screw I tested it and worked fine. But then I put back every screw and closed the phone and it just shows the apple logo forever. It restarts and show the apple logo again, forever. I got NO blue or red screen, just the apple logo, then it shuts down and restarts. I tried testing back the old LCD just in case I could have damaged the new LCD flex cables but no, it shows the same problem. I tried hard reset, even in DFU mode, but when restoring with iTunes it just throws an error. I think I maybe damaged the flex cable that comes from the proximity sensor&front camera while pushing it with a metal tool. So I disconnected it and tried powering the phone and still the same issue. So my question is. Will the phone power on while having the proximity sensor disconnected? It it does, then I have a major problem. If it is not supposed to turn on without that connector, then I can buy the cable and try again. I feel so bad because I just messed my friend’s phone and I want to find a solution. Thanks all in advance. Javier
Any possibility or indication of pry damage or long screw damage? Long screw damage is where you use the wrong screw for something near or on the board and it damages the traces under the grommet. Are you sure you kept good track of your screws and where you put them? If this is not a possibility, I would try a new good quality screen. EDIT: I see you said it was fine until you put the screws back in. I bet you have long screw damage.
