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iPhone 6S Plus Won't Turn On


A client sent us a iPhone 6S, according to his description, the phone did not fall, no water damage, but it suddenly had no response to the charger. Why did this happen, let's diagnose and test step by step.

First of all, open the iPhone to test it. It leaks 100mA, turn on the phone, it can enter iOS normally. The replacement of external configuration and charging is still unresponsive. The test voltage of iPhone battery socket is only 0.6V. According to our repair experience, it was caused by U2. Remove iPhone U2 IC, but iPhone still leaks 100mA, and the resistance of the bottom pin is normal. 


Replace the new iPhone U2 IC, assemble iPhone and test it. It charges reasonably. After a period of time, even if we do not use iPhone, the battery is still burning fast. We need to find out where the loopholes are.

Remove the iPhone motherboard again and connect it to DC power supply to test, after heating a while, we can feel the iPhone WIFI IC is overheat. 6S and later iPhone wifi are bound together with the iPhone Nand flash, we have to remove the iPhone Nand flash and untied WiFi，so we can replace the iPhone WIFI IC. After remove the iPhone WIFI IC, test the iPhone again, now the iPhone doesn't leak.


Measure the resistance of the iPhone with a digital multimeter. The data is normal. Now we can make sure that the motherboard is normal. The leak of the iPhone was caused by WiFi IC damage. Protect other components under the iPhone Nand flash, use QUICK 861DW Hot Wind Repair Station to remove the iPhone Nand flash, and then unlock the WiFi.


Clean up the solder pad, and then use JC Pro1000s programmer to untie the WIFI. Now, soldering the new iPhone WIFI module IC and iPhone Nand flash, and then install them. We have known that after replace the new IC, we can't use turn on iPhone by iPhone battery, we need to connect it to DC Power supply to turn it on, so this will avoid short circuit to burn components. Untied WIFI doesn't need to flash the iPhone, the data of iPhone Nand falsh won't lost. If you are not good for remove the iPhone Nand flash, you can backup it before remove it.

Install the iPhone, all functions tested are normal, the repairs end!

More cell phone repair skills please read on www.vipfixphone.com

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