Headset Path - LG GU280 Service Manual

4.17 Headset path

QSC6240 HPH_OUT_R_N, HPH_OUT_L_P
R404,R405 IC401(MUIC)
Connect the phone to network
equipment and setup call.
Setup 1KHz tone out
and insert headset.
Can you hear the tone?
Sine wave appears at
CN401 pin2,3?
Sine wave appears at
R404 ,R405?
Sine wave appears at
C530,C531?
Change the Main board
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Only for training and service purposes
C530,C531
CN401 (u USB Connector)
Start
YES
NO
YES
NO
YES
NO
YES
NO
IC500(Audio Sub System)
END
Change the Headset
Check the MUIC
Change the Main board
Check the Audio Sub System
Change the Main board
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4. TROUBLE SHOOTING
LGE Internal Use Only