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LGE Internal Use Only
Copyright © 2009 LG Electronics. Inc. All right reserved.
Only for training and service purposes
4. TROUBLE SHOOTING
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CHECKING FLOW
START
Does the audio
profile of the phone
change to the
earphone mode?
Check the voltage Level
CN302 pin8 = Low?
Replace U101 or Change Board
Re-solder CN302 or Change
another Ear- Mic set and Try again
Mic
Earphone
Go to MIC
Trouble section
Re-solder causal
component
(CN302)
Check the signal Level at
HSMIC.
Is it about 1.2~1.5V?
Change another Ear-Mic set and Try again
Acoustic
Does waveform at
U101.HSOL
fluctuate?
Replace U101 or
Change the board
Does waveform at
CN302 pin4,5 fluctuate?
Re-solder causal
component
(CN302,C321 etc.)
Change another Ear-Mic set and Try again
Yes
Yes
Yes
Yes
No
No
No
No
No