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Tutorial: iPhone 7 White Apple Logo Repair

We received an iPhone 7 from customer, error 4013 is reported when reboot system in data cable mode. The most frequent problem on iPhone 7 devices is baseband part, which is often encountered by iPhone repair technicians.

After 6S, if the baseband can't be identified, device will reboot with the white apple logo and not be able to enter the system. Maybe beginners will think that there is a problem with the Nand chip, no progress bar when restore system. If the baseband part is damaged, the error code can not be reported until 80%. But the iPhone 7 generation basically has a problem with the baseband. The repair process can be divided into the following steps:


1. Use Fluke digital multimeter to measure if the capacitance is short circuit to the ground? If yes, it can basically exclude and reboot, but the short circuit of the baseband CPU fault is 45%, the power failure is 45%, and the other 10% possibility is short circuit. Most of them are easy to fix except for CPU short circuit.

2. If there is no short circuit parts, change the power supply and try to restore system again.

3. If the above solutions are not effective, basically it means the baseband CPU has problem, you need to reweld baseband CPU.

This is the baseband CPU pserdo soldering problem. Remove it with QUICK 861DW hot air station and reweld again.

The baseband CPU of iPhone 7 is close to the main CPU. When it is removed, it should pay attention to heat insulation, so that CPU can be flameproof, and then the next step is to clean solder pad.

After reinstall the baseband CPU, iPhone 7 can turn on normally.

For iPhone 7 devices, it basically a baseband problem, technicians rarely encounter other problems, the repair ends here!

If you have any other problems for professional cell phone repair, please check on www.vipfixphone.com

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