LG OLED77C9PTA Service Manual page 29

Standard Repair Process
Error
symptom
Vertical/Horizontal bar, residual image, light spot
☞A6
Check color condition by input
- External Input
- AV / Component
- HDMI
☞A8
Check Test pattern
External device screen error-Color error
Check
Check S/W 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/Component
- HDMI
Y
N
Y
☞ A7
Check and
Y
Normal? replace Link
Cable(Vx1)
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,
AV and HDMI by connecting
Jig, pattern Generator ,Set-
top Box etc.
5
Established
date
Revised date
N
Screen
Replace Main B/D
normal?
Y
End
Screen
normal?
Request repair for
external device
Screen
normal?
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5/17
Replace
Module
N
Screen
normal?
Y
End
Replace
N
Main B/D /
Module
Y
Y
Replace
N
Main B/D /
Module