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iPhone 6 water damage - How to reboot?

How to fix iPhone after water damage? we heard from customer that he can't turn on his iPhone after water incident.  He tried to tear down and fix the touch flex cable and some Wi-Fi parts.  But after some time, it stops working again.  How tn o reboot it under such situation?

First we tear down it and see that the waterproof label discolored.



The waterproof label in normal iPhone is white.


After plugging adjustable DC power supply, it shows large current. We judge that the voltage of standby circuit is short circuit. Use the diode gear of multimeter to measure it and find that PP_VCC_MAIN is short circuit. Observing the motherboard carefully, we find the capacitor C5202_RF near Wi-Fi chip is a little dark and its tin plate drops a little. Remove C5202_RF and measure the voltage of PP_VCC_MAIN, which is no longer short circuit.


Energize iPhone and turn it on. Now it can get into IOS system normally. We think it recovers now, but after using for a while, iPhone generates heat badly and the battery drains quickly. Misfortunes never come alone. For those iPhones that can be turned on and get into IOS system normally but generates heat badly and the battery drains quickly, they must have somewhere that is short circuit at the subordinate circuits. The troubleshoot way is to test each function in IOS system. The abnormal part is the faulty point. After testing each function, we find that the compass function is abnormal. Every time we open compass, we need to calibrate it, as shown in the following picture.


Although it is calibrated, the directions it shows are wrong


At the same time, we test the gravity sense function and it is normal


Based on the tested results, we conclude that the problems which cause high heat and quick battery drain happen at the compass circuits. Use multimeter to measure the power supply of compass and find that PP3V0_IMU voltage is short circuit.


Power supply chip outputs PP3V0_IMU and it is filtered by capacitor C1902. Then it is offered to compass chip U1901 (NONSTUFF on C1902 is not installed). The circuit of compass chip is shown in the picture.

There are several possibilities that cause short circuit of PP3V0_IMU voltage.
(1)The power supply chip is damaged.
(2)C1902 is damaged.
(3)The power supply chip is damaged.


Under the repair rules the simple first and the complicated later, remove C1902


Measure the diode data of PP3V0_IMU again. It recovers to normal one 455


Reassemble iPhone and turn it on to enter IOS system. IPhone does not generate heat after using for a while. Compass function recovers. Trouble is removed.

Well, it's complete process for fixing iPhone water damage, hope this will help you.
More professional skills read at www.fixphone.com

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