Mic Trouble - LG KE590 Service Manual

4. TROUBLE SHOOTING
z MIC Trouble
START
NO
NO
Voltage across R100 or L100
MICBIAS Voltage of U103
Replace U103
is about 2.5V?
is about 2.5V?
YES
Re-solder R100 & L100
NO
Check the signal
level at each side of MIC100.
Replace MIC100
Is it a few tens mVAC?
YES
NO
Check the soldering of
Replace U103
R140,R141,C121,C122
change the Main Board
END
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