LG 55SK9000PUA Service Manual page 31

Standard Repair Process
Error
symptom
First of all, Check whether all of cables between board is inserted properly or not.
(Main B/D↔ Power B/D, EPI Cable, Speaker Cable, IR B/D Cable,,,)
No video
Normal
Normal audio
audio
N
Move to No
video/No audio
※Precaution ☞A4 & A2
Always check & record S/W Version and White
Balance value before replacing the Main Board
A. Video error
No video/ Normal audio
☞A1
Y
Check lock
voltage
Check Power Board (Module) 24V output
☞A9
Repair Power
Board or parts
☞A9
Y Check Power
0V
Board (Main)
20V, 12V etc.
N
Normal Y
Replace module
voltage
N
Replace Main Board
1
Established
date
Revised date
Y
Normal
Replace Main Board
voltage
N
Repair Power
Board or parts
End
Re-enter White Balance value
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