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After I replaced my iphones6s broken screen it started to overheat when charging and charge percentage will decrease really fast, like from 40% to 15% in about 3 min
Josselyn Lagos, Found this info. on your issue searching the net. Overheating problems after screen replacement, problem could be bad battery/damage to the battery connector or perhaps a power IC/component on mother board loose or damaged. You will have to disassemble phone again and check battery connector/motherboard and inspect for damage pins on battery/motherboard connectors and for damaged loose components. Disassembly guide link below. Good luck. I hope this helped you out, if so let me know by pressing the helpful button. iPhone 6s Battery Replacement
This happens cz display IC is not matching with mother board power supply to display ic. Change display and istall original
