Maintenance Process (Reception) - Huawei P20 Maintenance Manual

4.17.3 Maintenance Process (Reception)

WCDMA reception failure
rectified after the software
signals received before U3301 based
on the non-signaling transmission of the
frequency band. Are the signals
Are the RF signals received
rectified after the related circuit is
2019-6-25
EML-L29V100R001 Advanced Maintenance Manual V2.1
Are the
wired specifications
normal?
No
Is the failure
is updated to the latest
version?
No
Is WCDMA transmission
normal?
Yes
Spot-check the RF
normal?
Yes
after U3301 normal?
No
Is the failure
replaced?
No
Replace the modem U300
Yes
Yes
No
No
Yes
Yes
Huawei Confidential
INTERNAL
Check whether the RF
connection cable is
normal and whether the
antenna spring is in
good contact
End
Rectify transmission
exceptions in the
preceding transmitter
Replace U3901, and
U3501 or U3401 in
sequence
End
End
Yes
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