LG -H422 Service Manual page 51

3.11.3 Main Mic
It's operating voice call(except speakerphone), voice recording, camcorder recording
Checking Flow
Start
Check the Mic signal by test mode
or Voice recording.
Check Mic hole &
rubber to make
the voice signal?
Check parts
about Bias and
signal
Mic works well?
Reconnect or
change Mic Voice
signal OK?
Change
MT6323(U4100).
Mic works well?
Change Main Board
End
LGE Internal Use Only
Yes
No
Yes
No
Yes
No
Yes
No
Check C4103,
C4104
52
3. TROUBLE SHOOTING
Image
Main
BOT
FB6920
C6920
C4103 C4104
Circuit Diagram
Check FB6920,
VMIC voltage
level (C6920)
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