Vertical lines on screen

iam also facing same problum,that problum wont start immedietly,when we r watching after 1 hr it will start

You had not fixed all connector properly.

If you wish to get some details; visit the site linked here. Pull up older posts.
http://electronicshelponline.blogspot.com/
Line faults & possible causes to LCD & Plasma screen are given with illustrations. You can get an idea about the fault to an extent. Faults to all LCD & Plasma screen are similar, irrespective of its brand and screen size.////

I think that you have dry solder joints on either the vertical scan board, the focus board, the line output stage, or the chroma panel. Hope this helps.

I think you have dry solder joints on the tv. Either on the chroma board, the vertical scan board, the line output board, or on the focus board. If you are going to do this yourself please take all necessary precautions against electric shock and discharge all capacitors that you can as a stray spark from one can cause damage to your tv and yourself. If you are not able to do this find a competant technician. Good luck.

same problem here with my panasonic 42"? less than a month old and started about a week ago

sound like panel defect

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.

Had the same problem.  Was quoted $800 to fix.  Searched the internet for 6 months and found this thread on avforums.com

 

http://www.avforums.com/forums/showthread.php?t=462873&highlight=black+line+on+plasma&page=4

 

Read through all the posts.  Very simple fix, but you have to have some mechanical inclinations or you can cause more problems than you started with.  I was up to 5 of the black lines, but decided to attempt the soldering these guys did and fixed it all for the cost of a soldering iron!  Even if you decide not to attempt it, it gives you somewhere to start to tell a technician.

IF THE LINE IS ABOUT 1INCH WIDE THE CHANCES ARE IT WILLBE YOUR PLASMA DISPLY THAT HAS GONE . WOULD BR CHEAPER TO BUY A NEW UNIT . HOWEVER TRY RINGING HITACHI EXPLAIN THE FAULT COMPLAIN THAT IT SHOULD OF LASTED LONGER THAN THE WARANTY AND SEE WHAT THEY WILL DO ABOUT IT