he mute switch, volume buttons, vibrator and the power button is connected to one flex cable. And the flex cable is connected to the motherboard under the LCD connector. Check if the connector is loosen or not
If you dropped your phone in water it is most likely that your phone 's motherboard is fried. The phone is trying to recover itself. You should probably say goodbye to your phone because Apple doesn't fix water damaged phone.
Trying this. Not sure if it will work 1) Backup your device via icloud (use assistive touch for home button) 2) Use a new touch id home button 3) Put your iPhone in DFU mode. Restore it via iTunes If it doesn't work: solution 1) Grab your original components and take your phone to the Apple store solution 2) 1) Put your original home button back in the phone 2) DFU restore your device 3) Jailbreak your device 4) Use a tweak called Virtual Home as alternative
According to Apple you would need to reinstall iTunes. And when Apple tells you to reinstall iTunes you know that's a dumba** response. Maybe it was caused by the hardware because the iPhone 6s also encountered the same problem and have to use the original touch id cable for it to work. Try put your original home button and front camera module in the new screen and see if it works