LG Electronics KS360 service manual Microphone trouble

5. Trouble shooting

5.7 Microphone trouble

Check Points

-Microphone hole

-MICBIAS & Signal come from

-Audio signal level of the Microphone

-Soldering of components

TP1 C320

MIC_N

22n

TP2 C318

MIC_P

22n

MIC
C321
39p
	L304
C319	100nH
39p
	L303
	100nH

C317
39p	EVLC14S02050

MICBIAS

TP3

L302 100nH

MIC300

1	P
2
3	G1
4	G2
	O

SPU0409HE5H-PB

VA300 C322 10u

START

Check microphone sound hole

Yes

Mic bias ON (2.5V)when call?( TP3,L302)

Yes

Check the signal level at ( TP1,2)each side of MIC300.

Yes

Replace Main PCB

No

Check mic. Bias line

NoReplace microphone

(MIC300)

TP1

TP2

TP3

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