Toshiba Child lock

You might want to try the same solution for the V-Chip (this might be the same thing as the child lock, it is worth a try) protection to see if this will help:

Changing V-Chip Settings for MV13L3, TV/VCR Combo 2001.

-Unplug your tv for 1 minute.
-Plug your tv in and turn it on.
-hold the volume down button on the tv at the same time you hold the "0" button down on the remote. This will bring up the "Set V-Chip" blue screen.
-Enter "0000" for the password and hit enter. Enter "0000" to confirm the password and hit enter.
-This will bring up the V-Chip set page. From this page you can: Turn Off the V-Chip, Change the Limits for viewing, etc.
-If you turn off the V-Chip setting, you will not have to deal with this problem again.