LG 32LG710H Service Manual page 51

Analog RF Audio Trouble shooting guide
Check TU100 Pin13(SIF)
Can you see the normal signal?
YES
Check the input (Pin AD19) of BCM3549((IC100).
Measure waveform at C636 because it's more easy to check.
Can you see the normal waveform?
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Only for training and service purposes
NO
Could you measure voltage of TU100& IIC lines?
Are they all normal?
You should replace TUNER.
NO
After checking audio signal line, you should decide to replace item or not.
NO
YES
You should check power line
& IIC lines.
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