Malfunction Phenomenon
The charger function is abnormal on this phone.
Trouble Shooting
The iPhone X no charging and appears charger symbol in the left top corner of the screen. Then we plugged into the power cable and stayed in shutdown status, the phone can be switched on.
In the first step, we need to check the cosmetic of the motherboard to see if there’s any pats mission, corrosion, deformation, etc. After checking, the cosmetic is fine.
According to the experience of repair, we need to check the charging boost inductance and energy storage capacitance on the charging circuit. After checking, we found the measured one-side pin of L3340 and L3341 diode value is different from another side.
But when we pressed it with the finger, the measured value back to normal. So we can conclude that the fault is related to the poor solder of L3340 and L3341.
Resolder the two inductors, or change new inductors.
Then solder the two layers of the motherboard and test the function again, the issue resolved.
iPhone X Motherboard Repair Course