LG OK99 Service Manual page 56

ELECTRICAL TROUBLESHOOTING GUIDE
NO AUDIO CHECK
OPTICAL
Is the
DVCC 3.3V supplied to
IC304 pin3?
YES
JK302
pin1 input signal
OK?
YES
IC304
pin27, 28, 29, 31 data
output signal
OK?
YES
A
A
YES
IC501
pin D1, E1 I2S clock signal
OK?
YES
IC501
pin E2 I2S data signal
OK?
YES
IC601
PWM data output signal
OK?
YES
B
NO
IC304 pin9, 10, 17, 18, 32
optical control input signal OK?
NO
Check VCC 3.3 VA
& optical jack.
NO
Replace IC304.
NO
NO
NO
3-31
NO
Check IC501.
Check IC501.
Replace IC601.
Copyright © 2018 LG Electronics Inc. All rights reserved.
Check control signal
from IC501.
Only for training and service purposes.