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Repair: IPhone 6P No Display

Received a iPhone 6P phone from one of our customers, he described that the main fault as the following:

When connect the iPhone motherboard with DC power supply, the current is normal,after installing the screen to test, there are no lights and no display. According to the customer's description, it is inferred that it sometimes displays and sometimes does not display. 


By observing the appearance of the motherboard, we can not directly determine the fault point, the measurement of the display base resistance to the ground and power supply are normal, after the replacement of display IC U1501, the iPhone 6P is still not displayed.

In view of the fact that the 6P motherboard is easy to get broken by pressure or false welded , we have to remove the U1501 and use Fluke digital multimeter to measure the pin resistance. Fortunately, when the B2 pin is measured no resistance, we know the fault is finally found. The B2 pin was supplied by the PP VCC MAIN through the booster coil L1519 (the normal value is more than 300 ohms).

When the blade is gently lifted, L1519 dropped, and even the base pin is broken. As shown in Picture 1.
 

Carefully remove the lead pin and connect it with jumper wire. As shown in Picture 2.


Replace the booster coil L1519, install to have a test, the iPhone 6P no display fault is solved.

If you want to get more professional phone repair skills and tools, please check on www.vipfixphone.com

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