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Hi, I have recently replaced the battery on an iphone 7 but it keeps getting stuck in boot loop. However when I put the original battery back in, it works fine. I then tried another spare iphone 7 battery I had and thats also causing a boot loop. I’ve never had this happen before, I don’t know if its just my luck that both new battery replacements are faulty, or there is something I am missing. Any help would be appreciated, thanks.
It could be the batteries but this symptom usually occurs due to either a faulty top flex assembly or a faulty home button flex. Disconnect the top screen flex and see if it boots. Than disconnect the home button flex. If it’s a faulty top flex assembly you can just purchase that part but if it turns out to be the home button flex you will need to purchase another screen.
Check iphone battery connector if there is any deformation if no clean it with PCB cleaner then try again. If no hope that will be hardware problem why? Old battery health is low(with low current) so when you replace the new one or a battery with higher current than the old one Charging ic or USB ic through will try to resist from booting due to high current. Best solution install that new battery then update software to cleare catches from the CPU and other
