LG SPM2 - Registered Trademarks and Licenses

3-8
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
NO SOUND
2-2. OPTICAL
2-2-1. Solution
Replace MAIN board.
2-2-2. How to troubleshoot (Countermeasure)
1) Please check VDD33A at L200 of JK101.
2) If VDD33A is OK, please check OPT_IN signal(R150) when optical mode.
3) If signal abnormal, replace MAIN board.
2-2-3. Service hint (Any picture / Remark)
OPTICAL IN
C158
10V/0.1uF
R164
3.9K
123
OUT
GND
VCC
RX
JK101
R149
10K
R150
33
C177
10V/0.1uF
D103
OPEN
L109
600ohm/0.5A
DGND
DGND
VDD33A
DGND




< MAIN board top view >




JK101
JK101
L109
L109
R150
R150