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I have this iPhone 7 given to me to repair brought not turning on or showing low battery completely dead opened it discovered battery totally drained then got a new battery with average voltage phone powered on then inserted cable to charge then it turn off like a reboot after coming up displayed charging then increasing once cable removed same thing. Please I need help on how to fix this, thank you.
If you have tried a new battery and it shows the same symptoms it will most likely be a faulty charging circuit IC. The most common one to fail is the Tristar IC. You will need to find a reputable repairer to fix the problem as it will require microsoldering.
