Samsung PN51E6500EFXZA - Manual (Page 323)

steps:
1. Select an application, and then open
the Tools menu using your remote.
2. Select
Lock . The Security window
appears.
3. Enter your security PIN using the
remote. If you have not created a
PIN, enter “0-0-0-0”.
4. A confirmation message screen
appears. Select OK . The message
screen closes and a lock symbol