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Tutorial: iPhone 5 Charging Part Repair


We are going to fix an iPhone 5 cell phone with charging failure today, as we know, the charging part of iPhone 5 is made up of Q2, U2 and U7. As shown in picture 1, the circuit diagram of the charging port J7 can be inquired on the WUXINJI dongle



The 5V voltage sent from the tail plug passes through the Q2 to send two 5V power supply. PP5V0_USB_PROTECT and PP5V0_USB_RPROT were sent to U7 and U2 respectively.

In addition, there are two detection pin in the middle of the battery contact J6! they pass through FL10, FL11 respectively and send to power IC-U7, FL10, FL11, in actual cell phone repair, it is found that the 2 pins are very easy to fall off, causing the cell phone can not be charged! and keep reboot again and again!

If there is a problem of charging, plug in the data cable, use Flukedigital multimeter to measure whether C304 has 5V output, and measure whether C272 has 5V output.

If not, you need to test the iPhone 5 charging port flex cable, short connect the Q2.


If both of them can be measured 5V, then the problem is in U2 or U7.


In addition, the battery detection pin problem will cause abnormal charging, the more charging, the less battery power will be, and also there will be automatic restart fault.

If you want to get more cell phone repair tutorials, please contact us on www.vipfixphone.com

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