I have a six year old Sony 50' plasma tv model

SOURCE: Vertical line on TV

usualy this problem is cause by the lcd drive board.

SOURCE: plasma TV with vertical lines

chake to make sure it is hooked up right and not lose

SOURCE: Vertical white line down centre of Soniq PT42SH plasma TV.

One of your "X" buffer boards is defective. In Panasonic plasma tv's they are located at the bootom of the set and connect directly to the plasma diplay panel via a thin ribbon cable. The board you want to replace will be directly in line with the discolored vertival line in the picture. The part number is on the circuit board and usualy starts with "tnp..." or "txp..."

SOURCE: red vertical line down right side of the screen

hi

I think your TV have a trouble inside lcd panel
the controller board contains driver IC. Deffective driver IC can cause of line display.



Three reasons why one vertical line accross screen can happen in LCD;

1.The missing signal from the controller IC to
LCD driver.
2. LCD driver IC itself defective
3. Dry contact in the tape carrier package.

Use masking or electrical tape to mark it where the line was located. press it if the line back to normal but when release your hand came back i think it was intermittent. Open the LCD panel


Use robber

Place the rubber on the top of TCP

Gently close back the top casing


Good luck...