オリジナル投稿者： Minho ,
I'm a little late to the party... You may have tried some of these suggestions but they're here for posterity. Please try them and get back to me by commenting on my answer. A bootlooping device can be caused by many things. Try these things (if you haven't already) to see if anything helps: * Can you plug it into a USB ammeter to see if there is any current flow? * Because this happened after a screen change, inspect, preferably under magnification, the area surrounding the connectors for any loose, dislodged or visibly damaged components * Also inspect the connectors for damaged pins or debris * Try a hard reset (Home & Power button for 10 secs) * Use a genuine Apple Lightning connector * Use a genuine Apple charging brick and let it charge overnight * Try to connect it to different computers (mac/pc if possible) with an updated iTunes * Put the phone in recovery mode (search DFU Mode). Careful, this can reset your data * Use 3uTools for putting it in and out of Recovery Mode * Use 3uTools to flash the firmware (you can't downgrade) * Check the condition of all the flexes (with magnification) * Disconnect the Front Camera Ribbon from the logic board and reboot your phone * Disconnect the screen assembly completely and see if iTunes will recognize the phone. Otherwise, you may have a logic board issue. If you are uncomfortable doing these steps, consider finding a repair shop to do the troubleshooting. A shop that also does micro-soldering can go deeper if the problem is not modular in nature.