LG KU730 Service Manual page 109

4. TROUBLE SHOOTING
4.17.2 Voice and Sound Path for Head_set
Voice and Multimedia Sound path for Head_Set as below:
MSM6275 HPH_R, HPH_L -> C300,C301 -> R303,R304 -> CN300 headset Jack (pin 4,5)
Connect the phone to network
equipment and setup call.
Setup 1KHz tone out
and insert headset.
Can you hear the tone?
Start
NO
Sine wave appears at
C300/C301?
NO
Sine wave appears at
R303/R304 ?
NO
Change the Main board
YES
YES
Change the Head_Set
YES
Re-solder headset Jack
- 110 -
END