LG LGV400 - Manual (Page 21)

19
To activate Knock Code feature
1
From the Home screen, tap Apps > Settings > Display > Lock
screen > Select screen lock > Knock Code.
2 This opens a screen that will guide you through how to select the unlock
sequence. You have to create a backup PIN as a safety measure in case
you forget your unlock sequence.
NOTE: KnockON is disabled when Knock Code is in use.