Huawei P20 Maintenance Manual

EML-L29V100R001 Advanced Maintenance Manual V2.1
INTERNAL
2019-6-25
Huawei Confidential
Page 27 of 67
4.3 LCD Failure
4.3.1 Maintenance Process
LCD failure
Test again and
re-debug the environment.
Does the failure recur?
Yes
Is there any
cosmetic defect (such
as spot defects, black
spots,
and damage)?
Is the LCD
BTB connector
fastened properly?
No
Yes
Perform cross
verification for the LCD
and PCBA
The LCD is
faulty
The PCBA is
faulty
Replace the LCD
and ask the MQE
to analyze the
faulty LCD
No
NTF
Report to the TE
and equipment
engineers for cause
analysis
Yes
The IPQC re-
checks the
failure
The PQE re-
checks the
failure
Replace the
LCD
No
The PQE
analyzes the
cause to
prevent
assembly risks
Re-assemble
the LCD
Check the
appearance. Use an X-ray
machine to check the PCBA.
Are there any soldering issues
on the PCBA, especially on the
BTB
connectors?
Ye
s
No
Is the voltage
of the LCD backlight
LED indicator normal
(LB1704~LB1707)?
Is the LCD
driver voltage normal
(LB1701、LB1702)?
Is the
LCD I/O power VDDIO
normal (C1027)?
Ye
s
No
If there are no soldering
issues, replace defective
components
No
Check whether
U1702 and peripheral
small components are
defective
If there are no
soldering
issues, replace
defective
components
Check whether U1701
and peripheral small
components are
defective
No
The PCBA process
engineers analyze the
cause
Repair the area
with soldering
issues
Ye
s
Ye
s
Is the
RST PWM TE signal
normal (R1723、
R1724、R1721)?
Ye
s
No
If there are no soldering
issues, replace defective
components
Is the
MIPI signal normal
(T1701~T1705)?
Ye
s
No
If there are no soldering
issues, replace defective
components
Replace U300

Huawei P20 Specifications

General

Panel type	TFT
Screen shape	Flat
Pixel density	428 ppi
Second display	No
Display diagonal	5.8 \
Touch technology	Multi-touch
Touchscreen type	Capacitive
Display resolution	2244 x 1080 pixels
Native aspect ratio	19:9
Rounded display corners	Yes
Display number of colors	16 million colors
Processor cores	4
Processor family	Hi-Silicon
Processor frequency	2.36 GHz
Coprocessor frequency	1.8 GHz
Processor architecture	ARM Cortex-A73
Coprocessor architecture	ARM Cortex-A53
RAM capacity	4 GB
Compatible memory cards	Not supported
Internal storage capacity	128 GB
Flash type	LED
Rear camera type	Dual camera
Front camera type	Single camera
Video recording modes	1080p, 2160p
Rear camera aperture number	1.8
Front camera aperture number	2
Rear camera resolution (numeric)	12 MP
Front camera resolution (numeric)	24 MP
Second rear camera aperture number	1.6
Second rear camera resolution (numeric)	20 MP
4G standard	LTE
2G standards	GSM
3G standards	WCDMA
SIM card type	NanoSIM
Wi-Fi standards	802.11a, Wi-Fi 5 (802.11ac), 802.11b, 802.11g, Wi-Fi 4 (802.11n)
Bluetooth version	4.2
Bluetooth profiles	A2DP, APT-X
SIM card capability	-
Mobile network generation	4G
Subscription type	No subscription
USB version	3.2 Gen 1 (3.1 Gen 1)
USB connector type	USB Type-C
HDMI ports quantity	0
Multimedia Messaging Service (MMS)	Multimedia Messaging Service (MMS) is a standard way to send messages that include multimedia content to and from a mobile phone over a cellular network
Form factor	Bar
Product color	Blue
Themes	Wallpapers
Graphics card	Mali-G72 MP12
Personalization	Icons, Menu, Shortcuts
Personal info management (PIM)	Alarm clock, Calculator, Calendar, Notes
Speakers	stereo
Audio formats supported	3GP, AAC, APE, FLAC, MIDI, MP3, OGG, WAV
Video formats supported	3G2, 3GP, ASF, H.264, MKV, MP4, WEBM
Platform	Android
Operating system installed	Android 8.1
Talk time (3G)	- h
Battery capacity	3400 mAh
Battery recharge time	1.5 h
Interface adapters included	USB Type-C - 3.5mm

Weight and Dimensions

Depth	7.65 mm
Width	70.8 mm
Height	149.1 mm
Weight	165 g