I have a KF-42E200A Sony Bravia LCD tv. Recently we had to replace the lamp. Since then a horizontal line appeared at the top of the screen and it has grown to about 3 inches now. The picture itself is good except for this red horizontal line running accross the top of the screen. What could be the problem?

Question edited for clarity.

Page 60 of the manual refers. The section in the menu is called 'Video'.

Manuals for KF-50WE620

Sony https://www.sony.ca > electronics > support > product
Find instruction manuals and brochures for KF-50WE620. ... require the software update recently announced for certain BRAVIA™ and Grand WEGA™ televisions ...

Manuals for KF-50WE620

Sony https://www.sony.com > electronics > support > product
Find instruction manuals and brochures for KF-50WE620. ... require the software update recently announced for certain BRAVIA™ and Grand WEGA™ televisions ...

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  Questions and Answers about KF-50WE620

  https://www.sony.com > support > kf-50we620 > faqs
  LCD Projection TV HD-Monitor Grand WEGA® / Included components may vary by country or region of purchase: RM-Y913 · Questions & Answers · Is this page helpful?

COUNT THE # AND SEQUENCE OF THE BLINKING...CONTACT SONY TECH SUPPORT

Log on to www.sony.co.uk or they have a phone number Sony Information Centre 08705 111 999 Mon-Fri,9am-5pm.Will try and find manuel,might have thrown out by mistake.

meder tv service......this can sometimes be due to t-controller board failingnot sending proper data to panel.....can order on shopjimmy.com or partstore.com....happy repairs....

the blink light of 5 times points me toward a lamp driver error(no high voltage of the lamp driver)other wise known as a ballast problem.

It sounds lcd screen problem and lcd panel (screen) will be replaced. Please check with local tv repair shop or nearest Sony service center for lcd screen replacement.

New bulb is just fine.
3 blink shows that lamp cover after replacement of bulb in TV is not fixed properly or not seated well in its position.
Put new bulb and carefully place back lamp cover in its position because lamp cover will press tinny safety switch inside that will send signal to system control of TV that lamp is installed properly.
Turn On TV and get vivid picture of Sony.
Thanks.

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.
Search the site by type in the "BRAND NAME" of your device; (Exclude the model number), in the "Search box at the top right of the display window of the Homepage" to get gathered related posts

Both sound like bad LCD panels. The following must be answered to confirm this:
Do the lines appear on all inputs/all signal sources?
Can they be seen in the OSD/menu?
If yes to both questions, it is likely that the LCD panel is bad

if the lines on your screen looks anything like the image below, you do have a problem with the lcd, problem is you need to replace what is called the light engin. unfortunatly the price of this part is just about as much as a new replacement tv. Get a sceond opinion fron a sony service center near you, as i cannot see your picute. good luck