Huawei P20 - Motor Failure; Maintenance Process

EML-L29V100R001 Advanced Maintenance Manual V2.1
INTERNAL
2019-6-25
Huawei Confidential
Page 38 of 67
4.9 Motor Failure
4.9.1 Maintenance Process
Motor
failure
Are the
motor and motor
cables damaged or
broken?
The motor or motor
cables are damaged,
dirty, or poorly
soldered, causing
contact problems
Perform cross verification
for the motor and PCBA to
locate the faulty component
The motor
is faulty
The PCBA
is faulty
Use a
microscope for
the check. Does the motor
circuit have cosmetic
defects?
Fail
Pass
Fail
Is the
voltage at both ends
of the motor
1.8 V?
If there are no
soldering issues,
replace U2301
Fail
Pass
Fail
Send the
motor to the
component
team or the
supplier for
analysis
Are components
missing or
deviated?
Ask PCBA
process engineers
to locate the cause