Connect the power supply at the two terminals to the 1.8v burner. It was found that the rosin on the surface of a capacitor melted, and the resistance of the two terminals was normal after deduction, and the main board was no longer leaking when it was powered on, and the current jumped normally by pressing the power-on key.
Separate the motherboard, check the solder joints of the motherboard to see if there are obvious virtual solder joints, and then measure the solder joints from the motherboard to the upper layer. It is found that the main board has obvious solder joints falling off. After the solder joint is repaired, the measured resistance is normal. Re-attach the upper and lower layers, and repair the fault.
iPhone 12 can't connect WiFi. Use a polishing pen to polish the middle layer pad, plant tin in the middle layer, and fix the fault.
iPhone 12 restarts repeatedly, it was found that there was a problem with the BTB connector 1 after the c1xt1 was removed and the system was removed.
iPhone 12 has no baseband, the motherboard separate, middle layer REBALLING,welding, fault repair.
iPhone 12 has no signal, the mobile phone is stuck when inputting the password, and the middle layer of the main board is not as good as welding, and the fault is repaired after welding is renewed.
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iPhone 12 does not turn on, main board Short circuit,The rosin smoke method, start Current heating test, remove the problem Capacitor, and repair the fault.
