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iPhone XS in boot loop when migrated Earpiece Speaker and Front Sensor Assembly from original screen is plugged into logic board. Booting while Earpiece Speaker and Front Sensor Assembly is disconnected works well, warning of no FaceID and ear speaker non functional. Dis - and Re- assembled 3 x carefully looking for ribbon stresses / any mechanical signs of why it is not working. I am at a loss. Now considering returning iFixit screen and going to Best Buy for a more costly repair. *Original screen became non responsive after a drop, but not immediately after. The original problem occurred about :45 mins later when the screen just became unresponsive / black.
If the device is boot looping with the ear speaker connected and then goes away when it’s disconnected then it’s not the screen. You may have caused a short in the ear speaker assembly resulting in this issue. You could send it to a board repair specialist for further diagnosis such as iPad Rehab or STS Telecom.
