LG H990ds - Audio Main Microphone Troubleshooting

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3. TROUBLE SHOOTING
Circuit Diagram
Image
It’s operating voice call(except speakerphone), voice recording, camcorder recording.
Checking Flow
Start
Check the MIC filter
And reconnect PCB
Hear the Voice
through the RCV
in loopback test ?
Change MIC
No
No
Yes
Change Main Board
End
Yes
Yes
3.13 Audio Main MIC
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