Störungsphänomen
iPhone XR can not be turned on with a large current when connecting with DC power machine
Störungsbeseitigung
We disassembled the phone and checked if there was any water damaged area or other obvious malfunction, when connected with DC power, the current is very large, in our experience, the malfunction normally from the following area in red color.
PP_BATT_VCC
PP_VDD_MAIN
PP_VDD_BOOST
We checked the diode values on the three lines, but all of them are ok. Then we turned down the output voltage of the DC power machine and connected with the motherboard to check which part was hot. Then we can feel the area around U5002 was hot.
We removed the shielding cover and checked the diode value on the capacitors around the chip, we found the caps in the red area as below was shorted. Then we tried to remove one by one, when we removed C5021, the short was gone. Then we put other caps back and replaced another capacitor, the problem was resolved.
English 
Español 
Français 
Deutsch 
Italiano