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I took the iPhone 5s apart to clean some fluff from the rear camera but after reassembling it won’t turn on. When I took it apart the first time it was stuck then suddenly opened and the home button flex cable connector and metal clip came off but it didn’t look damaged. I’ve since replaced the home button and flex cable but it’s still not turning on. Any suggestions ? Update (01/07/2017) Thanks I’ve not got another battery but when I connect it to a PC iTunes starts and says can’t connect to iPhone because it locked but nothing on the phone display
Try swapping in a known good battery and charging port if you can get access to one. Then try plugging it into iTunes, if it turns on perfectly fine, then narrow it down to one part. If it doesn’t connect to iTunes, your board is most likely bad.
You have shorted the anode filter bead on the backlight circuit. A local repairer can fix this easy. Always remove the battery 1st!
Backlight ic is on the logic board, but if you are lucky and the ic isn’t damage then a new screen will fix the problem, don’t forget to disconnect the battery first and place the screws in the correct order ( to prevent damage the logic board ) on the metal plate that covers the 3 connectors of the screen. Sorry for my poor English.