Red line on screen, Plasma TV help.

Need some more info. Does it happen on every input? How old is the TV?

Try changing the input device to something you are sure works. Switch off TV manually, switch off power, remove plug and retry after 48 hours. If problem persists, please refer it to a qualified service technician.

Filter capacitors (more than 1) in the main power supply

1. Frist on the BURN MODE.
2. Check whether same
Vertical lines on screen ?? 3. If yes ..?
4. Then change the LOGIC BOARD or PDP

I had the same problem -red, vertical bars along the right side of my Samsung 42" Plasma- and this is what fixed it: Removed unterminated cable.
I had hooked up an HD video camera to the set about two weeks ago. While I disconnected the camera I left the other end of the connector cable plugged into the T.V.. As I've since learned from friends who work in television, this is what's called an "unterminated cable" -meaning one end is unconnected. It can lead to problems with electrical interference and appears to have been the problem in this case; When I disconnected this cable from the T.V. the red bars went away.
So, check your cables. Make sure everything is properly connected and get rid of anything that might be picking up interference.

Philips 50 inch plasma tv no video but has sound

IF THE LINES ARE ON LEFT SIDE ITS THE LEFT BUFFER BOARD AND VICE VERSA THEY ARE ON THE BOTTOM OF YOUR TV HOPE THIS HELPS YOU OUT

I work for a auth LG service center and each time I have had this symptom we had to either change what called the T_CON control board or the Plasma display panel itself. You need to cocntact LG @ 800-253-0000 report your problem and they will find a service center in your area you should have 1 year warranty parts and labor.

I had the same problem -red, vertical bars along the right side of my Samsung 42" Plasma- and this is what fixed it: Removed unterminated cable.  
I had hooked up an HD video camera to the set about two weeks ago.  While I disconnected the camera I left the other end of the connector cable plugged into the T.V..  As I've since learned from friends who work in television, this is what's called an "unterminated cable" -meaning one end is unconnected.  It can lead to problems with electrical interference and appears to have been the problem in this case;  When I disconnected this cable from the T.V. the red bars went away.
So, check your cables.  Make sure everything is properly connected and get rid of anything that might be picking up interference.  
Hope this makes sense.