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my i phone 6 plus wont turn on after battery got empty. before that while i am charging the charging percentage remains same. there i no increaing. like that i charrged for 1 day. there is no change. but when i connect charger some times one percentage will increase or decrease. when charger disconnect it bcome old condition.
If you have a Mac, connect it to one of the USB ports and run Coconut Battery application on it to see the status of the battery. https://www.coconut-flavour.com/coconutb… If it needs replacing, here’s how to do it: iPhone 6 Plus Battery Replacement
if a replacement battery doesn’t fix it then it sounds to be the charging circuit.