How to Fix Lines on a TV

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Updated September 7, 2022

Did you know that about 47% of U.S households own a Smart TV? Well, TVs are the most popular household devices all over the world due to their current affordable price. Have you ever experienced lines on your flat-screen TV?

KEY TAKEAWAYS:

  • Most times, when your TV shows vertical lines, it is usually a problem with the T-Con board.
  • Sometimes, knocking gently at the back of the TV might solve the problem temporarily.
  • Before replacing the T-Con board, make sure you note both the TV and T-Con board model numbers.

It’s a common problem with many low-end TVs and perhaps the most annoying fault for any user. You can get a top-rated TV to avoid all this. But if this happens to you, don’t panic! We’ve outlined a simple guide on how to fix lines on a TV.

  • Difficulty: Moderate
  • Time Required: 25 minutes
  • Total Steps: 4
  • Tools Needed: Screwdriver and multimeter.

What causes Lines on a TV Screen

Most times, when your TV shows vertical lines, it’s usually a problem with the T-Con board. But at times, it can be as simple as a loosely fitted wire.

If your TV shows vertical colored lines, it could also be due to the following:

  • Loose board
  • Damaged screen
  • Control board grounding issue

Sometimes, knocking gently at the back of the TV might solve the problem temporarily. You may be wondering how big your 24-inch tv is and where exactly to knock but just locate the affected area and knock at the back. . If this sorts out your problem, your T-Con board could be faulty or have a loose cable.

What to do If your TV shows Lines

When you first experience your TV showing lines, gently tap on different areas on the back panel. Depending on the fault, you’ll begin to see various lines disappear. If this happens, it is likely due to a loose wiring cable. In other instances, you may see black spots on your screen but you can simply fix the dead pixels on your tv before replacing it.

It is essential to note that tapping on the back of your TV panel when it shows colored lines is not a permanent solution to the problem. However, it may prevent vertical lines from showing temporarily.

To permanently fix lines showing on your TV, you’ll need to troubleshoot the problem and find out the specific fault on your T-Con board or wiring harness that might be faulty, loose, or damaged.

Fixing Line on your TV Screen

  1. First, unplug your TV from the mains and place it on a flat surface face-down with a towel underneath. Then, with a screwdriver, unscrew all the screws on the back panel and lift it off.
  2. The T-con board varies greatly in shape depending on the TV manufacturer. However, its location is always at the bottom of the LED panel.
  3. Remove any wiring cabling on the T-Con board and blow for dust. Check for any physical damage and insert it back gently.
  4. Next, you need to test for T-Con Board Voltage. With your multimeter set at AC, check the VGH that supplies the pulse amplifier circuit source driver and gate. The voltage needs to be 25 to 30v. The VGL should be -7 to -15, the AVdd voltage for the Gamma ic should be around 15v to 18v. The Vdd voltage for the digital circuits on T-Con modules should be at 3.3v and 1.8v or 1.2v.

If any T-Con board voltage measurement isn’t accurate, the T-Con board might be damaged and needs replacement. Before purchasing a replacement T-Con board for your TV, write down the TV and T-Con board model number to get the right fit for your Television.

Now that you have fixed the lines on your TV, you may want to look at other guides to know what to do should something come up in the future. If that’s the case we have a couple of great guides on one of the most important pieces of a TV, the remote. In these articles, you can learn how to reset the tv remote or if something is acting up with it, how to fix a tv remote.

F.A.Q.S

What causes colored lines on TV screens?

Most times, when your TV shows vertical lines, it is usually a problem with the T-Con board. But at times, it can be as simple as a loosely fitted wire.


Will tapping my TV at the back help remove lines on the screen?

When you first experience your TV showing lines, gently tap on different areas on the back panel. Depending on the fault, you’ll begin to see various lines disappear. If this happens, it is likely due to a loose wiring cable.


How can I permanently get rid of lines on my TV?

To permanently fix lines showing on your TV, you’ll need to troubleshoot the problem and find out the specific wiring harness that might be faulty, loose, or damaged.


Where is the T-Con board located on my TV?

The T-Con board varies greatly in shape depending on the TV manufacturer. However, its location is always at the bottom of the LED panel.

How will I know if my T-Con board is faulty?

You need to test for T-Con Board Voltage with your multimeter.



STAT: About 47% of U.S households own a Smart TV as of June 2019. In addition, smart TV ownership increased by 8% between June 2018 and June 2019 compared to other devices that either changed minimally or not at all (source)

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