Charging problem with battery
So i have a strange case going which i have been working on for a few weeks now.
A customer came in with he’s 6S because the phone was dead and not charging at all. I testet this with a USB voltage measure unit and confirmed that the phone does not take any charge what so ever.
Naturally i suspected the battery and replaced it. The phone was working fine and was charging like normal. Then the customer comes back with the same problem. I tried charging it while using the USB voltage measure unit and it said 0.00V. So i took the battery out and measured it to 3.26V. The phone needs 3.8V to start but not to charge. I placed the battery on a charging plate (activation plate). I had it there until the battery reached 4.05V and then put it back in the phone. Again phone turned on and received charging fine. I charged the phone to 100% and left it on without charger over night.
I came back the day after and the phone was off and again didn’t receive any charging. So i checked the battery voltage again and measured it to 3.03V. I put the battery back on charging plate again and charged it to 4.05V. I put the battery back into the phone, the phone turns on and receives charging just fine.
I have tried this with 4 different batteries from different suppliers including the original one. The result is the same every time. I now suspect the Power Management IC.
Anyone out there experience this?
Anyone knows how to fix it or what to do?
Is there something else i can test?
Thanks in advance for all answers!
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