Huawei nova5i mobile phone Won't Turn On repair

Huawei nova5i mobile phone Won’t Turn On repair

Machine model: Huawei nova5i
Customer description: fell behind the mobile phone Won’t Turn On
Test results: mobile phone Won’t Turn On, powered on large current.
Fault analysis: The mobile phone is broken down due to falling, and the power-on is large current. It is preliminarily determined that there are components damaged Short circuit.
Mobile phone repairAmong them, the fault of Short circuit no booting is the easiest to repair. First of all, it is necessary to determine the obvious fault point by visual inspection, and measure whether the fault point component is Short circuit. If no fault is found in the preliminary inspection, power up the motherboard, touch the part with high temperature on the motherboard with your hand, and measure whether this part of components is Short circuit. If the failure point is still not found,Then check by The rosin smoke method, smoke Colophony (Solder)on the VCC part of the main board, and power on to observe the melted component of Colophony (Solder), which is the fault point of Colophony (Solder).
By touching, it is found that the chip temperature in the lower left corner of the motherboard is on the high side. Open Xinzhizao Soft software, open Boardview of Huawei nova5i, and find the position of high temperature chip.
This area of the motherboard was fumigated with Colophony (Solder). After powering on, it was found that Capacitor C2411 and chip U2403 had Colophony (Solder)melting.

Huawei nova5i mobile phone Won’t Turn On repair figure 1.

Huawei nova5i mobile phone Won’t Turn On repair figure 2.

Then open the motherboard schematic to check, and find that this is an coder power amplifier chip. At the same time,Colophony (Solder)melts, and the fault does not necessarily appear on two components at the same time. According to normal conditions, first remove Capacitor C2411, and then repair the fault after removing Capacitor.