Check Signal format
Is it supported?
Check the RGB Cable
YES
MAIN B’D JK405 Check
Replace MAIN B’D JK405
YES
NO
NO
YES
Check MAIN B’D C207 (Video)
R2030 (HSYNC)
R2031 (VSYNC)
Replace
MAIN B’D C207 or R2030 or R2031
NO
Replace MAIN B’D IC 100
YES
MAIN B’D JK405 Pin #2
Video signal ?
R446 has Vsync ?
R447 has Hsync ?
Making
Revision
2009. 2 . 1
9/25
LCD TV
Symptom
RGB No Video Problem
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Summary of Contents for 37LH50YD
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