LG H990ds Service Manual page 72

3. TROUBLE SHOOTING
3.13 Audio sub(2 ) MIC
nd
It's operating Speakerphone call.
Image
Checking Flow
Start
Check the MIC filter
And reconnect PCB
Hear the Voice
through the SPK
in 2mic loopback
test ?
Yes Yes
No
Circuit Diagram
Change MIC
No
Yes
Change Main Board
End
72
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