The volume of Xiaomi 8 cannot be adjusted for repair

The volume of Xiaomi 8 cannot be adjusted for repair

After getting the mobile phone, start the test, press and hold the volume up button and there is no response, and the sound level has not changed. Press and hold the volume down button, and the sound of the mobile phone will be reduced. Take out the motherboard after disassembling, and measure the grounding value as OL, indicating that the motherboard is disconnected.

Machine model: Xiaomi 8

Fault symptom: the volume of the mobile phone cannot be adjusted.

Maintenance process:

After getting the mobile phone, start the test, press and hold the volume up button and there is no response, and the sound level has not changed. Press and hold the volume down button, and the sound of the mobile phone will be reduced. Take out the motherboard after disassembling, and measure the grounding value as OL, indicating that the motherboard is disconnected.

The volume of Xiaomi 8 cannot be adjusted for maintenance. Figure 1

Open the 8: 00 bitmap of Xinzhi software Xiaomi, check the volume, press the resistor R601, and then connect it to the power chip U601.

The volume of Xiaomi 8 cannot be adjusted for maintenance. Figure 2

So I removed the power supply, took the foot, and flew to the capacitor R601 in the lower left corner.

The volume of Xiaomi 8 cannot be adjusted. Maintenance Figure 3

The ground value measured by multimeter again is 473, and the value is normal. Restart the machine after installation, press the volume up key and volume down key of the mobile phone, the volume can be adjusted and the fault can be repaired.

The volume of Xiaomi 8 cannot be adjusted. Maintenance Figure 4