Chosen Solution
I got my phone last year and now my phone kept shutting itself off and the only way I could turn it on is when I plug it in, and now that it’s on, Diagnostics would show up ask a question and if I exit Diagnostics, it would power down by itself… What should I do? I have turned it on and off a lot of times and it’s still happening.
The weakest link on the iPhone 6S is the battery so it is possible that the battery is almost completely dead. That would be the first thing to replace to see if it solves the problem.
