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Fixed: iPhone 6s stuck on white apple logo

Got a apple 6S from one of our customers, the phone is stuck on white apple logo when turning it on, sometimes it turn into black screen. Why this situation appears? Let's have a look in this article!


Try to enter iTunes mode online, we are not able to enter iTunes data cable mode but DFU mode,which can be online, and we can confirm that it has nothing to do with U2 fault. There is automatic black screen after the white apple appears. The computer prompt can not jump from DFU to recovery mode. This is often caused by iPhone NAND or CPU.

The power supply of the iPhone 6s can be measured according to the WUXINJI schematic diagram. The two 1.8V are on C1534 and C1560 respectively, 0.9V is on C1548, and 3.0V is on C1502, and the NAND voltage is normal. You need to take down the pin resistance of the NAND to see if there is a break between the CPU and the NAND chip.

At the same time, you need to test whether the NAND itself is damaged. The protective measures should be pre heated to remove glue, and the temperature is about 220 degrees. Choose the thinnest blade, except for the right side of the adhesive, there must be some small resistance around it. If it falls, it must be filled. The QUICK 861DW hot air gun can be selected to remove the NAND chip, and the heat transfer area is large, the temperature should be set about 350 degrees. When heated to a certain extent, you can tentatively take the thin slices and insert them into the hard disk. When the tin starts melting, you can pick them up. Do not use great force to avoid dropping the NAND and pads. (temperature is related to equipment and personal techniques).


After testing, the NAND pin is normal, take the WL PCIE programmer to read the data.


NAND data display normal, remove broken line and NAND problem, reinstall the NAND to reflash the iPhone, all the function is normal now!

If the article is useful for your iPhone repair, please check more information on www.vipfixphone.com

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