Connect the mainboard with the power supply for repairing the machine, and the mainboard is very hot, indicating that the mainboard has a short circuit. This situation is generally caused by the breakdown of the filter capacitor, and the lower board is smoked with rosin, and then the power supply of the lower board repair machine is burned separately to lock the fault point.
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.
According to the point bitmap, measure the battery connecting seat position and find that the battery seat position is short-circuited; It was found that a capacitor next to the CPU on the B side of the upper layer was short-circuited. After replacing the capacitor, the fault was repaired.
iPhone 12 Pro Max shows no service and no signal., make up the point on the upper board, and fix the fault.
iPhone 12 Pro Max can't be turned on, layered motherboard burns, replaced damaged capacitors, fault fixed.
iPhone 12 Pro MAX after water damage,no booting was replaced by FPC, and the main board water damage chip was rebuilt.
The iPhone 12 Pro Max phone does not display when it is turned on. After replacing the fault Capacitor, the boot display is normal and the fault is eliminated.
iPhone 12 Pro Max Camera can't be used, and the control chip U6500 of flash VCC is damaged, which is repaired after replacement.
The speaker of iPhone 12 Pro Max mobile phone has noise. After replacing the audio power amplifier chip, the fault is repaired.
