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How to Fix Dead iPhone A8 Processor

We are going to fix a water damaged iPhone 6, UMT board, which is not online with 80mA, reset to measure is only 0.8V, and it's not short circuit. After removing the iPhone USB management IC, display touch IC (U1501) and replacing PMU, the result is same, resistance value is also normal. When the CPU is removed, the reset value is normal 1.8, the value is lower again after installing reset voltage, now, the iPhone CPU fault is determined. The reset pullup resistance R0206 is 100K, and the voltage becomes 1.6V after the change of the 2.2K resistance.


The upper cover current is a little higher, and the iPhone screen is not displayed when install to test the iPhone 6 device. The power supply required for the measurement screen is normal, connect Ace assistant which shows "please unlock the device", so it indicates that the system has been entered, and the failure is from CPU. Then PP1V0 is measured short circuit, a few points  on CPU are all short circuited. Now, we can only install the CPU back.


Directly connect 1.0V to this point, the current is 350A and the voltage is 0.8V. It seems hopeful, so we connect it with PP1V2_SDRAM directly.


Reboot the iPhone6 we can see the iPhone 6 turns on a bright screen, but the current is about 400mA, the data is kept.


More cell phone repair knowledge please visit www.vipfixphone.com
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