iPhone 6s shuts down with over 40% battery power
Hi
My iPhone 6S continually shuts down with 40% or more battery power. If I plug it into my computer to charge it, it will come back on showing 40% power (or whatever it was on before it shut down).., Sometimes I am able to use it again if I unplug it but other times it will immediately shut down again. I have seen the DFU mode suggestion, but how do you do this with iCloud? I have no iTunes back up and when I plug my phone into my MacBook iTunes doesn't even come up...
I am so tired of this expensive device repeatedly failing me... I did an Apple diagnostics test over the phone and of course everything came up just fine!
My nearest Apple Service Centre is a way aways and I am pretty sure I will get the same thing, everything tests fine, and I cannot make the phone do this thing on demand.
Frustration!!!
iPhone 4, iOS 5