This information was found on the Magnavox customer support website. http://www.m4c.magnavox.com/cgi-bin/dcbint/cpindex.pl?scy=US&slg=AEN&cat=TV_CONVENTIONAL_CA&sct=TV_LARGE_25_29_SU&grp=TV_GR&session=20090602222010_220.127.116.11&ctn=27MS343S&mid=Link_UserManuals&hlt=Link_UserManuals
It is located in the pdf copy of the owners manual on page 23. If this information does not help you solve your problem you can call Magnavox customer support at this telephone number 1-800-705-200. Give them the model number of you television and the problem you are having the smart lock feature. They will be able to help you solve the problem. I hope this information help you with you problem 1 Press MENU to show the on-screen
2 Press VOL+ or VOL- to highlight SET.
3 Press CH+ or CH- to highlight
4 Press VOL+ or VOL- to display the
SECRET CODE screen.
5 Press VOL+ (on the remote) and the
CH+ button on the front of the TV
at the same time.
6 Press the Number buttons to
enter a four-digit code. The code will
appear on the screen as you enter it.
The code “0000” is the default of the
TV. If you have not set up a code previously,
then “0000” is the code.You cannot
use “0000” after you set your own
code (unless you reset the code to
7 Press MENU to save the code.
8 The Parental Control menu will appear
next. Press TV/AV/EXIT to remove
the menu, or continue from this point
to change your Parental Control settings