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Fixed: iPhone 7P Won't Turn On


We received a damaged iPhone 7 Plus, the malfunction is iPhone 7 Plus can't turn on. First, we need to connect it to the DC power supply to test the charging current of iPhone, the current will jump to about 200 Ma, which is unstable. The computer is unable to identify iPhone when connected, and it cannot be activated.


Disassemble the iPhone to have a test, opening tools are essential to tear down the iPhone, then remove the iPhone motherboard. Measure the iPhone motherboard with Fluke 15B+ Digital Multimeter, there is no current, which means no leakage. Trigger it and it shows large current, the current up to 1.9A. Now, apply some rosin on iPhone logic board and use QUICK 861DW hot air rework station to heat, it's turning white.


Does the iPhone main power break down? Let's check iPhone bitmap on the WUXINJI Dongle, we found the iPhone Nand flash power is also  in the hot spot, first we need to measure the iPhone Nand flash to check if it is short circuit. After measurement, the iPhone Nand flash is short circuit.


Now, remove the iPhone Nand flash around the tape of the power supply large capacitor, and then apply rosin on it, adjust the ammeter to 3 V and heating this circuit by QUICK 861DW hot air rework station, this capacitor is short circuit, so we remove it.


The data is normal when we measure again. Put it on the activation board and add some power, finally, the iPhone 7P can turn on successfully.

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

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