Chosen Solution
Dear to all, this is my first topic. I have a big problem with my iPhone 6. It restarts casually, sometimes after reboot, when i insert the code, instantly it reboots. Sometimes, also when it is locked, it reboots and when it try to start sometimes it is not able to start and reboot for 4 or 5 times. I have replaced 2 original battery and i have tried to disable all lock methods (finger and code) and tried to hard reset with iTunes but the problem is always the same. Can someone help me? Thanks
Is this something that occurred suddenly, for no apparent reason or was it following some kind of event like a drop, coming into contact with water or repair attempt? I would open up the phone and do a good visual inspection to see if anything is out of place or if you find evidence of water or other debris. I would start by disconnecting all of the connectors except the battery, Dock and screen (LCD & Digitizer, do not connect the FCAM & Sensor). Plug in your phone and then check to see if the phone is more stable. If it is not, then you may have a defective screen, Dock or a Logic Board issue. If you want, you could try a new or known-good screen and Dock to eliminate the last variable. If the bare-bones approach works, then add one flex at a time until the problem reappears and replace the defective component. I would start with the Home Button, Rear Camera, Volume & Power Button, Front Camera and Sensors.
Did you try a DFU restore after replacing the battery with a known good one?
