When I watch a DVD on my Jensen tv I have to go back to factory settings and rescan my channels

Try with the remote to direct enter the channel number (with the number buttons and or enter) If set makes it there go into menu for option to manually add it to the set memory.

Not likely a problem with your set.

It sounds that your TV is locked by someway. Just unlock it. Proceed the following.
Many Jensen TVs have a parental lock that can be set to stop children from watching certain television shows or channels. In order to activate or deactivate the controls, you have to know the four-digit code or parental lock passcode. If you forget the passcode or if the lock gets set accidentally, you can still unlock the TV.

• Turn on the TV using the remote control. In most cases, you will need the original Jensen remote to unlock the TV if you aren't sure of the unlock code. You can purchase an original replacement online if necessary.

• Look at the screen. If you see a red key on the bottom of the screen, press "Function" and "Mute" on the remote at the same time. This will unlock the channel. Do this if you want to bypass the lock to watch a certain show or channel while leaving the TV locked. All other channels will remain locked and the TV will lock again when it is turned off.

• Unlock all of the channels on the TV by entering 0711 or 3308. These are the Jensen factory reset codes that will reset the TV to the original factory settings. By doing this, you will loose any information that you have stored in the TV, such as channel labels and schedules. You will have to program the TV again by going through the entire initial set up.

•Call the technical support service number in your owner's manual if neither of those codes work. A technician can help you troubleshoot the television as the problem may not be the parental lock feature. Have the model number and serial number of the TV available when you call.
• Take your television to a TV repair shop if neither of the codes work and the TV locked by itself while it was turned on. In this case, the TV may need to be rewired.

Many Jensen TVs have a parental lock that can be set to stop children from watching certain television shows or channels. In order to activate or deactivate the controls, you have to know the four-digit code or parental lock passcode. If you forget the passcode or if the lock gets set accidentally, you can still unlock the TV.

Turn on the TV using the remote control. In most cases, you will need the original Jensen remote to unlock the TV if you aren't sure of the unlock code. You can purchase an original replacement online if necessary.

• Look at the screen. If you see a red key on the bottom of the screen, press "Function" and "Mute" on the remote at the same time. This will unlock the channel. Do this if you want to bypass the lock to watch a certain show or channel while leaving the TV locked. All other channels will remain locked and the TV will lock again when it is turned off.

• Unlock all of the channels on the TV by entering 0711 or 3308. These are the Jensen factory reset codes that will reset the TV to the original factory settings. By doing this, you will loose any information that you have stored in the TV, such as channel labels and schedules. You will have to program the TV again by going through the entire initial set up.

•Call the technical support service number in your owner's manual if neither of those codes work. A technician can help you troubleshoot the television as the problem may not be the parental lock feature. Have the model number and serial number of the TV available when you call.
• Take your television to a TV repair shop if neither of the codes work and the TV locked by itself while it was turned on. In this case, the TV may need to be rewired

You could just reset back to factory defaults and let it rescan for the channels again.

Turn the TV on, hold the display button on the remote until the screen goes black. Turn off the TV and back on and it should work. Hope this helps! =]

Hello
To unloxk your Jensen TV do the following.

1. Turn on the TV using the remote control. In most cases, you will need the original Jensen remote to unlock the TV if you aren't sure of the unlock code. You can purchase an original replacement online if necessary.

2. Look at the screen. If you see a red key on the bottom of the screen, press "Function" and "Mute" on the remote at the same time. This will unlock the channel. Do this if you want to bypass the lock to watch a certain show or channel while leaving the TV locked. All other channels will remain locked and the TV will lock again when it is turned off.

3. Unlock all of the channels on the TV by entering 0711 or 3308. These are the Jensen factory reset codes that will reset the TV to the original factory settings. By doing this, you will loose any information that you have stored in the TV, such as channel labels and schedules. You will have to program the TV again by going through the entire initial set up.

4. Call the technical support service number in your owner's manual if neither of those codes work. A technician can help you troubleshoot the television as the problem may not be the parental lock feature. Have the model number and serial number of the TV available when you call.
5. Take your television to a TV repair shop if neither of the codes work and the TV locked by itself while it was turned on. In this case, the TV may need to be rewired
OK.

Main system control memory IC fault. This is a very small IC; have 8 solder terminals, and can be located very near to the main system control-chroma IC. Check and replace it. Be sure to replace it with the same number printed on it; in all respect. Otherwise, it won't go. http://electronicshelponline.blogspot.com/ Before replacing it, try a reset to this set, and then check.
There are two methods to reset TVs. The first is simple to do; a Hard Reset. The other is somewhat skilled; is a Factory Reset (System Reset). To make it a hard reset, just unplug the TV from AC mains wall socket, and re-plug it back after 15 minutes or so. If you do this by overnight is better. This procedure will make it a hard reset. If you want to make it a system reset [Factory Reset]; you have to enter its service mode option, and select the factory reset option. If you wish to get some details; check the site linked here.

Be sure your tv is programing with a correct signal. Air or cable channels, and that you do have a line going into the RF connector [antenna signal]. If you have a satellite or cable box your tv will only tune to channel 3. Also, if you are logged into a dvd player or vcr...you will only have one channel memory. Remove any of the external players [games,dvd,vcr etc.] And retune with auto program!

Use ur original remote of the tv u want setup to the DTV box go menu switch cable back to air
reseption.Set tv channel 3 hook up the DTV box and rescan the channels u have it.

Try this: press "Function" and "Mute" on the remote at the same time. This will unlock the channel. Do this if you want to bypass the lock to watch a certain show or channel while leaving the TV locked. All other channels will remain locked and the TV will lock again when it is turned off.
Unlock all of the channels on the TV by entering 0711 or 3308. These are the Jensen factory reset codes that will reset the TV to the original factory settings. By doing this, you will loose any information that you have stored in the TV, such as channel labels and schedules. You will have to program the TV again by going through the entire initial set up.