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The front camera in my iPhone 7 stopped working randomly, so I bought a replacement and put it in. The front camera was working after the switch, but I get the message “Touch ID - Unable to activate Touch ID on this iPhone ." Not only does Touch ID not work, the home button doesn’t either. I have checked the flex cable and it isn’t damaged, and I have factory reset my phone which didn’t fix the issue. Not sure what could be the problem at this point. Any help is appreciated.
When you say check flex cable, did you check both flex cables? The flex cable from the home button and the flex cable(s) coming from the screen? It’s common to partially tear one of the flex cables when lifting up / removing the screen from the phone. You’ll have to remove the LCD shield plate behind the screen to visually inspect those two screen cables. If one of them are torn, the screen needs to be replaced to fix the problem. Here’s a guide on removing the LCD shield plate: iPhone 7 LCD Shield Plate Replacement
