Huawei P20 - Page 13

EML-L29V100R001 Advanced Maintenance Manual V2.1
INTERNAL
2019-6-25
Huawei Confidential
Page 13 of 67
No.
Designator
Description
Symptom
Remarks
3
U1000
Main system
PMU HI6421
Various faults may occur. For
example, various power supply faults,
or the phone cannot be powered on.
4
U1101
Sub-PMU, which
provides power
for SOC
peripheral
devices' I/O
VDD_PERI_0V75 has a power supply
fault, the phone cannot be powered on,
the system freezes, or the phone has
electricity leakage.
5
U1201
PMU buckboost
The phone cannot be powered on.
6
X1201
System 38.4
MHz clock
The phone cannot be powered on.
7
U1301
PMU 6422,
which provides
power for the big
core and GPU
The phone cannot be powered on, the
system freezes or restarts, or the phone
has electricity leakage.
8
U1400
Phone ROM
UFS2.1
The phone cannot be powered on. The
main symptom is that the phone access
Com1.0 automatically after powered
on.
9
J1501
Battery holder
The phone cannot be powered on or
charged.
10
U1602
Charging
management
chip
The phone cannot be charged, the
phone has electricity leakage, or the
phone cannot be powered.
11
U1701
Backlight drive
chip
There is not backlight, and the phone
has a black screen.
The phone screen
is normal, but the
phone appears to
have a black
screen due to lack
of backlight.
12
U1702
LCD display
drive chip
There is backlight, but without display.
The phone has a black, white, or erratic
screen.
13
J1701
TP/LCD module
connector
There is a fingerprint sensor,
touchscreen, or display failure.
14
U1801
DC charging
switch
The phone cannot start SuperCharge.
15
U1901
Flash drive chip
The flash cannot be turned on.
16
U1902
RGB sensor
There are issues, such as temperature
sensor failure and image color cast.
17
J2001
Rear camera
connector
The rear camera malfunctions.