Chosen Solution
Hello, I can try and be of assistance. So as it is not restarting when front camera is disconnected - I would assume there is a problem round here. Check all pins (send a picture of pins on logic board if you like). Also, maybe try a different screen replacement, it could be a faulty screen (potentially drawing more power than it should).
I also have similar problem when the volume is increased to maximize while watching a video on my iPhone XS it reboot. I also tried connecting the phone to a Bluetooth speaker by increasing the volume but it didn’t reboot. Any help?? I have also done a lot of research and I landed on changing the usb flex but I have tried that one yet hmmm
