LG 42LW650G/S/T/W Service Manual page 55

Standard Repair Process
LCD TV
symptom
First of all, Check whether all of cables between board is inserted properly or not.
(Main B/D↔ Power B/D, LVDS Cable,Speaker Cable,IR B/D Cable,,,)
No video
Normal
Normal audio
audio
N
Move to No
video/No audio
※Precaution
☞A7 & A3
Always check & record S/W Version and White
Balance value before replacing the Main Board
Copyright © 2011 LG Electronics. Inc. All rights reserved.
Only for training and service purposes
A. Video error
Error
No video/ Normal audio
☞A1
Y
Check Back Light
On with naked eye
☞A2
Check Power Board 24v output
Repair Power
Board or parts
☞A4
Y
Check Power
On
Board
12v,3.5v etc.
N
Y
Normal Replace Inverter
voltage or module
N
Replace Main Board
1
Established
2010. 12 .14
date
Revised date
Y Replace T-con
Normal
Board or module
voltage
And Adjust VCOM
☞A28
N
Repair Power
Board or parts
End
Re-enter White Balance value
1/14
LGE Internal Use Only