Sony LCD TV Troubleshooting: Vertical Lines in the Screen

The simplest issue to troubleshoot and fix is one that involves the input signal. Start by removing and reseating the video cable both on the TV and the video source. If that does not solve the problem, use a different cable, ideally one that you know to be good. If you are still experiencing the issue, switch to a different source. For example, if you are watching a television station through your coaxial cable, switch to the HDMI input or the VGA input, or connect your computer to the TV. If the lines continue to appear, the issue is likely internal.

On LCD TVs, each pixel is made up of three colored, semi-transparent crystals. When various amounts of electrical current are applied to the crystals, they grow or shrink. Light is shined through the crystals, producing the color combinations that the TV displays. If any of the pixels in a vertical row have died, then the entire row will be solid black. Dead pixels cannot be repaired. The LCD screen will need to be replaced to repair the TV. If there is a white or flickering line, the issue more likely involves the internal connection from the signal processors to the screen.

Each pixel on the screen is connected separately through a tiny wire to the signal control circuit boards. These wires are connected on the left and/or right edges of the screen, and can become dislodged or disconnected. A useful way to determine if this has happened is to spray canned air along the left and right edges of the screen while looking at the picture where the vertical line appears. If the line disappears after spraying the cold air along the edges of the screen, it is likely a bonding problem that was temporarily solved by cooling the wires, which improves conductivity. The bonding failure cannot be permanently repaired, so the LCD screen will need to be replaced. You may be able to temporarily remove the vertical line by squeezing the side of the LCD screen where the bonding failure has occurred, but this is not a permanent or reliable solution.

LCD televisions have myriad connections and circuit boards that process the incoming signals from various sources and display the information on the screen. After powering down and unplugging the TV, you can disassemble it to check the internal connections. It is possible that a connection between one of the circuit boards and another component has come loose. Reseat all the connections carefully, reassemble the TV, and check to see if the line still appears. If it is still there, then one of the circuit boards, such as the T-CON board, may need to be replaced.