LG 55QNED85SQA Service Manual page 74

Standard Repair Process Detail Technical Manual
Error
Established
E. Etc
symptom
date
Revised
Content A20
Adjustment Test pattern - ADJ Key
date
P-ONLY  HDMI HOT(Yellow button)  CH '+' or '-'
You can view 11 types of patterns using the ADJ Key
Checking item :
1. Defective pixel
2. Residual image
3. MODULE error (ADD-BAR,SCAN BAR..)
4. Video error (Classification of MODULE or Main-B/D!)
A20