LG CM7420 Service Manual page 59

ELECTRICAL TROUBLESHOOTING GUIDE
A
IC501
Pin4, 5, 6 I2S data output
signal OK?
YES
IC507
Pin2, 17 DAC_BCK/LRCK input
signal OK?
YES
IC507
Pin7,14 BEAT_LRCK/BCK output
signal OK?
YES
IC501
Pin6 BEAT_DAC_DATA output
signal OK?
YES
IC801
I2S input signal
OK?
YES
IC801
BEAT_DATA output signal
OK?
YES
B
NO
Replace IC501.
NO
Check IC507.
NO
Replace IC507.
NO
Check IC501.
NO
Check IC501.
NO
Check IC801.
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