Malfunction Phenomenon
The phone won’t be turned on with a large current. It’s faint appears apple logo on the screen.
Trouble Shooting
For the iPhone X iPhone X Not turn on issue. First, take apart the phone and run the cosmetic inspection of the motherboard. If everything is OK, then detach the two layers of the motherboard from each other. And connected with the DC power supply, the current reading on the ammeter is jumping to 150MA, which is abnormal.
So we need to check the power supply of PP_VCC_MAIN, PP_BATT_VCC PP_VDD_BOOST, the measured diode value is normal. According to experience repair, the fault is related to load where is located in the lines of power supply. So we measured the lines of 1.8V power supply diode value is smaller than normal value. Then we check it under the Microscope and found the C2643 is damaged.
As we can see the capacitor is located in next to the NAND flash chip. So we can conclude that the fault is related to C2643.
After removing it directly, then make the upper layer and lower layer solder together, and assemble it and test again, problem resolved.
