Chosen Solution
It blanks on and off and gets really hot. I let it go dead so it can cool down,but when I cut it back on sometimes it let u go to the setting because I tried to reset it and the apple sign will pop up then it will go back to blanking off
Disassemble the phone and hook it up on the bench so you can feel the logic board. Turn it on. Let it get hot and check to see what’s hot. Is it the battery? If so, that’s a simple fix - replace it! If it’s something on the logic board then you have a PCB level component that needs replacing, which is not an easy fix. Have you tried plugging it in and turning it on? Does it boot all the way up then? Have you tried putting it in DFU mode and restoring it? Did it get all the way through the process? I had one iPhone 5 that had corrupted firmware from an update. It behaved similarly. The DFU mode restore fixed it.
