Chosen Solution
I had repaired many screens, batteries, lightning ports and so on over the past 5 years, always successfully without any issues at all whatsoever. Out of nowhere, my iphone 7 would just start to die at a high percentage, which was odd.. so I went out and bought another battery. Upon installing the battery, I had about 2 hours of use before it completely would not turn on at all whilst it was plugged in. I purchased another battery again, frustrated, and the same issue happened except i got a whopping 4 hours. I am at a loss here, and have tried everything in regards to any metal components touching other metal components, no ribbon cables are touching any screw or screw hole, etc. Keep in mind that my phone was working flawlessly until this happened out of the blue. (Each battery replacement were not done with cheap batteries, and all of them showed that they were charging until it blanked on me) I am posting this for any type of advice you guys may be able to provide to help me further investigate and try to fix this issue. I do not want to buy a whole new logic board with a home button or a new charging port if these are not actually needed.
Unfortunately, troubleshooting these kinds of problems usually requires access to some good quality (or known-good) replacement parts. Based on your diagnostics to date, I would suspect a logic board issue but you will need to have that looked at by an experienced micro-solderer in order to know for sure. If multiple batteries don’t work and there are o tears in any of the flexes and no damage to any connectors, the only other real option is a logic board issue. Electronic components do fail spontaneously and this is probably what’s at play here.
