Huawei P20 Maintenance Manual page 24

Figure 4-4 Charging failure maintenance principle 3
Test Item
Test Point
TP1 (no actual test point; resistance rest)
TP2
TP3 (no actual test point; you can test the
pull-up resistor)
TP4 (no actual test point; you can test the
pull-up resistor)
2019-6-25
EML-L29V100R001 Advanced Maintenance Manual V2.1
Huawei Confidential
Network
VCHG_USB
VCHG_USB_CON
I2C6_SCL
I2C6_SDA
INTERNAL
Normal Standard
5 V or 0 V
5 V
A waveform is available after
charging is enabled.
A waveform is available
after charging is enabled.
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