Yes, MOtvGUY is right, to remove the smartlock, you will need an original replacement remote for this TV set. There is the way is is done :
Philips and Magnavox
Philips sets use a four digit code to control the v-chip. The override code for Philip sets is 0711, although it may say "Incorrect code" the first time to trick you. If "Incorrect code" is displayed, simply enter 0711 again. To use it hit the MENU key to get to the menus. Go up or down until you reach AUTOLOCK or SMARTLOCK, depending on the model, and push the "right arrow" key on the remote. Enter the override code, and enter it a second time if it says it is incorrect.
Once in the AUTOLOCK or SMARTLOCK menu, go to BLOCK, and push the "right arrow" key. Go to BLOCKING OPTIONS and press the "right arrow" key. Go to MASTER DISABLE and press the "right arrow" key so that it says "MASTER DISABLE ON". The v-chip is now reset.
You can find these instructions plus more on V-chip and lockouts HERE
I'm pretty sure you'll need the remote and the numeric keys to enter the password to remove the lock.
Yes, MOtvGUY is right, to remove the smartlock, you will need an original replacement remote for this TV set. There is the way is is done :
Philips and Magnavox
Philips sets use a four digit code to control the v-chip. The override code for Philip sets is 0711, although it may say "Incorrect code" the first time to trick you. If "Incorrect code" is displayed, simply enter 0711 again. To use it hit the MENU key to get to the menus. Go up or down until you reach AUTOLOCK or SMARTLOCK, depending on the model, and push the "right arrow" key on the remote. Enter the override code, and enter it a second time if it says it is incorrect.
Once in the AUTOLOCK or SMARTLOCK menu, go to BLOCK, and push the "right arrow" key. Go to BLOCKING OPTIONS and press the "right arrow" key. Go to MASTER DISABLE and press the "right arrow" key so that it says "MASTER DISABLE ON". The v-chip is now reset.
You can find these instructions plus more on V-chip and lockouts HERE
Good Luck