Redmi note 7Pro Won't Turn On repair

Redmi note 7Pro Won’t Turn On repair

Machine model: Redmi note 7pro
Test results:Won’t Turn On mobile phone, boot display charging icon, plug in charger can boot.
Fault analysis: the mobile phone prompts charging when it is turned on. It may be that the mobile phone battery is dead, or the mobile phone battery VCC is abnormal. Plug in the charger to turn on the phone normally, which proves that other parts of the mobile phone are normal, so the locking fault lies in the part between the battery and the power chip.First open the Xinzhizao Soft software to find the relevant components.Battery BTB connector, charging chip, power chip.

Redmi note 7Pro Won’t Turn On repair Figure 1.

Then open the circuit schematic.Find schematic of j1301 BTB connector and measure whether pin of BTB connector is normal.

Redmi note 7Pro Won’t Turn On repair Figure 2.

Find the schematic of the power chip again, and measure whether the circuit between the battery and the power chip is normal.

Redmi note 7Pro Won’t Turn On repair Figure 3.

Finally, through the measurement, it is found that the output of the power chip VCC is abnormal, but the input VCC is normal, which proves that the power chip has been damaged and recovered after replacement.