The iPhone user complained that his iPhone 6 plus won't boot now, and he has no idea for how to fix it. After check the iPhone, we got best solution for it.
Use phone opening tools to tear down the iPhone, measure the iPhone motherboard with DC power supply, before we press the iPhone power button, the data is normal; when we press the iPhone power button, the current directly jump from 400mA to 1A, which means the iPhone is short circuit.
Remove the iPhone Nand flash and put it under the microscope, carefully clean up the iPhone Nand flash, we found there are 2 pins was dropped. Measure these two pins to check whether is good or not, the result is that they are ground connection (the normal point value should be infinite).
Disconnect the jump wire and then re-weld it again by using PPD 861D Plus, after processing, measure the iPhone 6 NAND CHIP, we find it's normal power supply 1.8V. Without NAND installation, we connect DC power supply to see the triggered current is 70mA, it's DFU mode when connect with computer(it happens when no NAND on motherboard or NAND doesn't match with CPU), then we remove the NAND on JC Pro1000s Test Fixture to see if it can be read, the result shows the NAND chip is not bad, now we re-install the NAND.
The
triggered current is still 70mA, so we suspect that the NAND chip is not
original, install the motherboard back and connect a computer with recovery
mode, we want to check whether it can read the serial number of NAND. It can be
read, so we continue to recover the data til succeed.
After finish the above steps, install the iPhone, press the iPhone power button, the Apple logo appears on iPhone display screen smoothly. After get into IOS, check iPhone functions on it, all works fine, the repairs end!
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