LG 65UP7700PUB Service Manual page 36

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, LVDS or EPI or CEDS 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 Back Light
On with naked eye
Check Power Board 13.2V output
☞A18
Repair Power
Board or parts
☞A18
Y Check Power
On
Board
13.2V etc.
N
Y Replace Inverter
Normal
voltage or module
N
Replace Main Board
1
Established
date
Revised date
Replace T-con/Main
Y
Normal
Board or module
voltage
N
Repair Power
Board or parts
End
Re-enter White Balance value
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