According to our ever repair experience, we need to check the inside and find the sources faults ,it it is necessary, we may need to replace it with a new one.
Check iPhone 5S circuit diagram on WUXINJI Dongle, we know that after plug the iPhone lightning cable, the charge voltage PP5V0_USB_PROT first passes through Q2, then to U2, and then to the iPhone power supply IC--U7, we can measure the voltage of 5V to U2 by Fluke 15B+ Digital Multimeter at point C272, and the 5V voltage can be measured at point C304.
If 5V can't be measured at C304 and C372 points, which means that Q2 is damaged. In this case, we need to short connect Q2，as shown in the following picture 1-1
If one has 5V and the other not, which means there is a disconnection. In this case, we will use QUICK 861DW hot air rework station to solder a jump wire from C304 to C272.
Note:
1. If the C304 or C272 doesn't have the voltage, it will cause iPhone can be charge only when it is turned off or is the hint that the accessory is not supported
2. The iPhone 5S USB control IC--U2 is easy to damage, and then cause iPhone cannot be charged, cannot connect to computer and won't boot issues, so we need to replace the iPhone USB charge IC--U2.
3. The damaged iPhone battery and iPhone tail plug flex cable also can cause iPhone charge failures, such as won't charge, "this accessory is not supported", or the percentage of charge icon is getting less when the iPhone in charging, so we need to replace the new iPhone batter or iPhone tail plug flex cable.
Then, check it again, charging and restarting it, check the charging process.
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