The iPhone XS can't be turned on after pressing the power button, after testing, we confimed it's caused by hardware problem, now let's get hardware solution to fix the iPhone XS boot failure.
Disassemble the iPhone XS by phone opening tools, connect the iPhone XS to the DC power supply to test the boot current, when press the iPhone power button, the current instantly reaches more than 800mA, and then drops to 0mA immediately.
Remove the iPhone display screen, disconnect the iPhone battery, and then remove the iPhone motherboard.
Use digital multimeter to measure the circuit of the power supply, we found the PP1V1_S2 is short circuited.
Log in to ZXW online account to check iPhone schematic diagram, we need to measure the capacitors on the PP1V1_S2 circuit. After measurement, we know that those capacitors are normal. Therefore, we suspect the problem is between the iPhone CPU and the iPhone motherboard, the iPhone CPU tin balls may have broken, and then cause the PP1V1_S2 short circuit.
Attach the iPhone XS motherboard upper layer to the SS-601K PCB fixture, apply some solder paste around the iPhone CPU, and then use BGA removal blade and hot air gun to remove the iPhone CPU.
After the iPhone CPU is removed, put iPhone motherboard under the Trinocular microscope, and then use BGA removal blade to remove the glue on the iPhone motherboard.
Next, put MJ 3D BGA reballing stencil on the iPhone CPU; apply some Mechanic solder paste to the BGA reballing stencil, and then use hot air gun to reball it.
After reballing, apply some solder paste on the iPhone motherboard, and then put iPhone CPU on the right position, use DES H95 hot air gun to solder it back the iPhone motherboard.
Now install the iPhone XS, press the power button, the Apple logo appears normally, and then the iPhone XS enters IOS system successfully ,the iPhone XS boot failure has been solved!
Disassemble the iPhone XS by phone opening tools, connect the iPhone XS to the DC power supply to test the boot current, when press the iPhone power button, the current instantly reaches more than 800mA, and then drops to 0mA immediately.
Remove the iPhone display screen, disconnect the iPhone battery, and then remove the iPhone motherboard.
Use digital multimeter to measure the circuit of the power supply, we found the PP1V1_S2 is short circuited.
Log in to ZXW online account to check iPhone schematic diagram, we need to measure the capacitors on the PP1V1_S2 circuit. After measurement, we know that those capacitors are normal. Therefore, we suspect the problem is between the iPhone CPU and the iPhone motherboard, the iPhone CPU tin balls may have broken, and then cause the PP1V1_S2 short circuit.
Attach the iPhone XS motherboard upper layer to the SS-601K PCB fixture, apply some solder paste around the iPhone CPU, and then use BGA removal blade and hot air gun to remove the iPhone CPU.
After the iPhone CPU is removed, put iPhone motherboard under the Trinocular microscope, and then use BGA removal blade to remove the glue on the iPhone motherboard.
Next, put MJ 3D BGA reballing stencil on the iPhone CPU; apply some Mechanic solder paste to the BGA reballing stencil, and then use hot air gun to reball it.
After reballing, apply some solder paste on the iPhone motherboard, and then put iPhone CPU on the right position, use DES H95 hot air gun to solder it back the iPhone motherboard.
Now install the iPhone XS, press the power button, the Apple logo appears normally, and then the iPhone XS enters IOS system successfully ,the iPhone XS boot failure has been solved!
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