LG 75SM9400PTA Service Manual page 39

Standard Repair Process
Error
symptom
☞A6
Check color by input
-External Input
-HDMI
☞A20
Check Test pattern
A. Video error
Color error
☞ A7
※ Check and
replace Link
Y
Color Cable
error? (EPI or Vx1 Cable)
and contact
condition
N
Check error color
input mode
External Input/
Component
error
HDMI
error
Established
Revised date
Y
Color
Replace Main B/D
error?
N
Check external External
device and Device/Cable
cable normal
Request repair
for external
device/cable
Check external External
device and
device/Cable
cable
normal
4
date
Y
Color
Replace module
error?
N
End
Y
Replace Main/T-con B/D
N
N
Y
Replace Main/T-con B/D
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