Samsung CT20D9WFX/RCL Service Manual page 25

Troubleshooting
5-4 Vertical Lines Appear or Screen
5-4
Check IC301 B+
16V-C,-13.5V-C
Normal
Check IC201S
Pin 21,22
(VDN,VDP)
Normal
Check / Replace
IC301
Abnormal
Check
R304,R305
D301,D302
Abnormal
Check
IC201S
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