Chosen Solution
Just changed iPhone 6 battery. When plugging in to charge, the phone charges OK and eventually the white screen with the Apple logo appears, and it turns on. But once turned on, the phone doesn’t charge past 1%. The battery icon in the top right of the screen doesn’t show a lightning strike, so once on it stops charging. I’m using a charger that is working correctly, as it charges well another iPhone (SE 2016). Is the replacement battery faulty?
It could be a faulty battery. Make sure the battery flex connector is sitting flush, maybe disconnect and reconnect again. If this doesn’t work you will need to rule the battery out by trying a replacement one. The other part that can cause this issue is the charge port assembly. I would try another battery first than replace the charge port if it is still not charging it will be a faulty charging IC in which case I would advise an upgrade.
