LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. TROUBLE SHOOTING
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4.20 Speaker phone path
MSM6280 LINE_OP,LINE_ON -> C314/R318, C315/R320 -> Audio AMP(U302)
-> Analog Switch(U301) -> CN601 -> CN901 -> Speaker
Start
Connect the phone to network
equipment and setup call
Setup 1KHz tone out
Sine wave appears at
C314/R318 and C315/R320?
Change the Main board
NO
SPK_AMP_EN(R312) is
2.5V?
Change the Main board
NO
YES
The sine wave appears at
SPK_N,SPK_P LCD FPCB?
YES
NO
Change the speaker
YES
Change the Main board
The sine wave appears at
?
Change the Main board
Check the Analog Switch
NO
YES
The sine wave appears at
PIN28,PIN29,CN601?
YES
Check LCD FPCB.
Check CN901
NO
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