LG 75UN8100PTB Service Manual page 25

Standard Repair Process
Error
symptom
First of all, Check whether all of cables between boards is assembled properly or not.
(Main B/D↔ Power B/D, Vx1 or EPI Cable, Speaker Cable, IR B/D Cable and so on)
No video
Normal
Normal audio
audio
N
Move to
No video/No audio
※Precaution
☞A2& A4
Always check & record S/W Version, White
Balance value before replacing the Main Board
A. Video error
No video / Normal audio
☞A1
Y
Check backlight on
with the naked eye
☞A18
Check voltage from Power B/D to backlight
Replace Power B/D
or repair parts
☞A18
Y
Check 13.2V from
On
Power B/D
N
Normal Y
Replace module
voltage
N
Replace Main Board
1
Established
date
Revised date
Y
Normal Replace T-con/Main B/D
or module
voltage
N
Repair Power B/D
or parts
End
Re-write Tool option, Area option and White Balance value
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