LG KM710 Service Manual page 85

4. Trouble Shooting
z MIC Trouble
START
Voltage across C628
or L602 is about 2.5V?
YES
Check the signal
level at each side of MIC600.
Is it a few tens mVAC?
YES
Check the soldering of
C630-C638,L603,L604
change the Main Board
END
LGE Internal Use Only
NO
MICBIAS Voltage of
U102 is about 2.5V?
Re-solder R100 & L100
NO
Replace MIC600
NO
Replace U102
- 86 -
NO
Replace U102
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