LG 28LM4 0B-PU Series, Service Manual, Page: 24 / 69

Established
date
Standard Repair Process
Revised date
1/13
Error
symptom
A. Video error
No video/ Normal audio
First of all, Check whether all of cables between board is inserted properly or not.
(Main B/D↔ Power B/D, LVDS or EPI Cable, Speaker Cable, IR B/D Cable,,,)
ත A18 ත A1
Normal
audio
Y
N
Move to No
No video
Normal audio
Check Back Light
On with naked eye
On
Y
N
Check Power
Board
12.5V etc.
Normal
voltage
Y
N
Replace T-con/Main
Board or module
R i P
Ch k P B d 12 5V t t
Move to No
video/No audio
Repair Power
Board or parts
Check Power Board 12.5V output
Normal
voltage Y Replace Inverter
or module
ත
A18
g
N
Repair Power
Board or parts
End
ϡ
Precaution
ත A4 & A2
Always check & record S/W Version and White
Balance value before replacing the Main Board
Replace Main Board
Re-enter White Balance value
ϡ
Precaution
ත A4 & & A2
- 24 -
2019