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Fixed: iPhone 6SP Half Black Screen Fault

Customer sent a iPhone 6S Plus, describes the fault is the phone screen is half black, after analysis we get to know that such a fault is generally a backlight circuit problem.


The last repairman described the iPhone motherboard has connected tin, so there was no direct test on DC power supply.

Disassemble the iPhone 6s Plus and observe the main board under LED Stereo Microscope, we find there is connected tin in the fingerprint base.


After cleaning up the board, we connect power supply to have a test, it is found that the fault is the half black screen, which is consistent with the customer description.

When use Fluke digital multimeter to measure the ground value of the iPhone touch base , it shows that the 6 pin of the display base are infinitely large, indicating that the pin is broken.

6 pin is backlight power supply, which is through the FL4211 inductor to the backlight chip, since the FL4211 inductor plate has been destroyed by the last repairman, we can not short connect again, can only fly jumper wire from the connected components.

So we connect from C4023 to C4211, as shown in picture 19-5-2.


Turn on the iPhone 6s Plus to have a test, all the functions are normal now!

If you want to get more technical support for cell phone repair, please check on www.vipfixphone.com
 

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