Headset Failure; Maintenance Process - Huawei P20 Maintenance Manual

4.13 Headset Failure

4.13.1 Maintenance Process

The components are
improperly installed in the
production line. Ask the PQE
to take corrective measures
YES
Replace the main FPC
2019-6-25
EML-L29V100R001 Advanced Maintenance Manual V2.1
Headset failure
Is the headset faulty?
Is the BTB
NO
connector of the main FPC
fastened to the PCBA
properly?
NO
Perform cross
verification. Is the main FPC
faulty?
Replace the
corresponding resistor
or capacitor.
Replace U2201
Replace U2102.
Huawei Confidential
YES
Replace the headset
NO
YES
Perform cross
verification. Is the PCBA
faulty?
NO
Check the resistance of networks
HS_FB, HSR_TEST, HSL_TEST,
HS_MIC_TEST, and HS_GND_TEST
in sequence.
NO
Is the
resistance of the networks
normal?
YES
YES
Is the DP HD
video normal?
NO
YES
Is the USB device normal?
NO
Replace U2101
INTERNAL
YES
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