LG OLED77CS LA Series Service Manual page 25

Standard Repair Process
Error
symptom
Vertical/Horizontal bar, residual image, light spot
☞A6
Check color condition by input
-External Input
-HDMI
Check Test pattern
External device screen error-Color error
Check S/W Check
Version
version
S/W Upgrade
Normal
screen?
End
A. Video error
Vertical / Horizontal bar, residual image,
light spot, external device color error
Check external
Y
Screen device
normal? connection
condition
N
Replace
module
Check screen
condition by input
N
-External Input
-AV
-HDMI/DVI
Y
N
Y
Revised date
☞ A7
Check and
Y
Normal? replace Link
Cable
N
Request repair
for external
device
Connect other external
device and cable
External
(Check normal operation of
Input
External Input, HDMI/DVI
error
by connecting Jig, pattern
Generator ,Set-top Box etc.
Connect other external
device and cable
(Check normal operation of
HDMI/
External Input, Component,
DVI
RGB and HDMI/DVI by
connecting Jig, pattern
Generator ,Set-top Box etc.
5
Established
date
N
Screen
Replace Main
normal?
Y
End
Screen
normal?
Request repair for
external device
Screen
normal?
Copyright © 2022 LG Electronics. Inc. All rights reserved.
Only for training and service purposes.
5/16
Replace
Module
N
Screen
normal?
Y
End
N Replace
Main B/D /
Module
Y
Y
N Replace
Main B/D /
Module