LG 42PM4700 Owner's Manual page 106

To lock system
❐
HOME ➾ Settings
Permits only specific programs by blocking channels or external input.
Select the Lock System
Block Channel
➙ LOCK ➙
to On.
Blocks the channels that contain inappropriate contents for
children. The channels can be selected but the screen is
blank and the audio is muted.
To watch a locked channel, enter the password.
Lock System