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iPhone 6 Display Failure after Replacing LCD

The iPhone 6 display is black after replacing LCD. After checking, the diode data of display socket is normal and all power supply for iPhone display IC output is normal. Testing by DC power supply, we find the iPhone current is abnormal. When press the iPhone power button, the boot current is obviously large.


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The current reached 100mA when press the power button. After remove the display tube, the current still the same, which means there is a short circuit. Measure the voltage output of each circuit of power supply with Fluke 15B+ Digital Multimeter, then surprised to find that there are really short circuit places.


LD010 is short circuit; we suspect that the filter capacitance on the circuit has been penetrated. After remove the iPhone power control IC, we found it is ground short circuit. Open the WUXINJI Dongle to check the iPhone schematic circuit, we found that this circuit is the display card image transmission MIPI data bus power supply.
CPU breakdown, the iPhone 6 doesn't display is possibly caused by physical damaged that the iPhone display screen electrostatic breakdown the CPU internal video card part. Put it under the 7-45X 180X Stereo Zoom Microscope, adjust the stable voltage to 1.5V, and then shock this circuit. At the shock moment, the power meter current jumps to more than 500 mA and then becomes 0. Shock it again, the current is not responding. Measuring the diode data shown is 180.

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Install the main power, and then connect it to DC power supply to turn it on, the current not start from 100mA, but start from normal data 60mA. Assemble the iPhone display screen to test; now the iPhone 6 can be displayed normally.


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