iPhone7 short-circuit current Won’t Turn On repair

iPhone7 short-circuit current Won’t Turn On repair

Failure model: iPhone 7
Fault symptom: mobile phone short-circuit current Won’t Turn On.
Maintenance process: According to the customer’s feedback, the current of Connect the power supply is shown in the figure:

iPhone7 short-circuit current Won’t Turn On repair Figure 1.

Connect DC power supply short-circuit current 536Ma, such as DC power supply short-circuit current, partly caused by the original damage of battery VCC directly, or by short-circuit current, the connected circuit of battery short-circuit current converted into motherboard main VCC. This current is more than 500 Ma. The method of DC power supply can be used to find the fault point or measure it as shown in the figure:

iPhone7 short-circuit current Won’t Turn On repair Figure 2.

According to past experience, this current is measured to PP_VDD_BOOST, and Short circuit, a secondary system to ground, is found, and Colophony (Solder)is smoked as shown in the figure:

iPhone7 short-circuit current Won’t Turn On repair Figure 3.

This Capacitor was the first to melt when it became dark, and the troubleshooting was deducted. During the installation test, it was found that the screen was not bright, and the test display was normal after changing the test screen.

iPhone7 short-circuit current Won’t Turn On repair Figure 4.