LG 43LJ55 -U Series Service Manual page 35

Standard Repair Process Detail Technical Manual
symptom
<ALL MODELS>
Copyright 2017 LG Electronics Inc. All rights reserved.
Only for training and service purposes
Error
A. Video error_Video error, video lag/stop
TUNER input signal strength checking method
Content
Established
date
Revised
date
All Setting  Channels
Manual Tuning
A3

Channel Tuning
When the signal is strong,
use the attenuator (-10dB, -
15dB, -20dB etc.)
LGE Internal Use Only
A3