Troubleshooting; Charging Failure; Maintenance Process - Huawei P20 Maintenance Manual

4 Troubleshooting

4.1 Charging Failure

4.1.1 Maintenance Process

Figure 4-1 Troubleshooting flowchart
Replace the
charger
Replace the
charging cable
Yes
Replace
U1801
2019-6-25
EML-L29V100R001 Advanced Maintenance Manual V2.1
No
Perform cross
verification. Is the
charger normal?
No
Perform cross
verification. Is the
charger normal?
Yes
No
The voltage
of VCHG_USB
is 0 V and that of
VCHG_USB_CONN is 5 V.
Is a direct charger
used?
No
Replace
U2101
Charging failure
Is the
battery damaged
or bulged? Is the
battery FPC
scratched?
Is the
battery connector
damaged on the
appearance?
Are the
voltages of VCHG_USB
and VCHG_USB_
CONN 5 V?
Do I2C6_SCL
and I2C6_SDA have
signals?
Check whether U1602 and U300 are
soldered properly. If no, re-solder them.
If yes, replace the chips
Huawei Confidential
INTERNAL
Yes
Replace the
battery
No
Replace the
connector
No
If the voltages are
both 0 V, check
No
whether the USB
connector and FPC
on the subsidiary
board are damaged.
If so, replace them
Yes
Yes
Replace U1602
No
Page 22 of 67