LG SL7Y Service Manual page 34

NO SOUND
2-2. OPTICAL
2-2-1. Solution
Replace MPEG/JACK board.
2-2-2. How to troubleshoot (Countermeasure)
1) Please check 3.3 VA at FB203.
2) If 3.3 VA is ok, please check OPT_IN signal (C228) when OPTICAL mode.
3) If signal is abnormal, replace MPEG/JACK board.
2-2-3. Service hint (Any picture / Remark)
FB203
PZ1608U221-1R4TF
JK201 JK201
J K 2 0 1
C 2 2 8
C 2 6 6
R 2 0 5
F B 3 1 5
R207 R207
C 2 1 6
I C 3 0 9
1
< MPEG/JACK board top view >
ONE POINT REPAIR GUIDE
OPTICAL
JK201
EAG37842011
OPTICAL JACK,192KHz
3.3VA
3 2 1
DGND
J K 2 0 4
R 2 3 6
F L 2 0 3
R 2 3 5
R207 100
R206 560
C266
100pF
DGND
< MPEG/JACK board bottom view >
3-9
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MPEG
OPT_SPDIF
MICOM
OPT_DET
C 2 1 3
C 2 1 5
F B 2 0 3
FB203 FB203
Only for training and service purposes.