Power Problem - LG UBK80 Service Manual

NO POWER PROBLEM
No power problem occurs when you power on the unit.
1-2. No 12 VA (Primary side)
1-2-1. Solution
Replace Q101, D104, R121, R123, IC101 on SMPS board.
1-2-2. How to troubleshoot (Countermeasure)
1) Check FET Q101 (Impedance between source and drain) and replace it.
2) Check D104, R121, R123 short or open and replace it.
3) Check IC101 and replace it.
1-2-3. Service hint (Any picture / Remark)
Stb
Pon
Q101
< SMPS board top view >
ONE POINT REPAIR GUIDE
AC Input
110V 230V
147V 312V
141V 307V
ST
DRV
4 5
OCP
6
BA
VCC
[0V]
2 7
FB/OLP
GND
1 8
IC101
FL102
<Refer>
100pF/1KV 624-087B
Q101
220pF/1KV 624-087H
470pF/1KV EAE60686401
1000pF/1KV 624-087J
<Refer (Rocp)>
0RS0350K619 0.35 &8/2W:65W
0RS0470K619 0.47 &8/2W:50W
0RS0750K619 0.75 &8/2W:30W
C107
680pF
R118
330
Stb:20.8V
Pon:21.9V
IC101
D104
< SMPS board bottom view >
3-28
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N3:14T/2UEW/ &U 0.45
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C111
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Only for training and service purposes.