Having half of your TV screen suddenly look different than the other half can be jarring and concerning. There are a few potential causes for this issue that are worth investigating.
Check the Source
The first thing to check is whether the issue is with the TV itself or with the source of the content you’re watching. Try displaying a solid color over the entire screen to see if the discoloration persists. You can do this by going into the TV’s menu and finding a screen test, display mode, or color test option.
If the test screen looks uniform, then the problem is likely with the source, like a cable box, streaming device, DVD player, or game console. Check the connections to make sure the cables are securely plugged in. Try swapping out cables if you have spares. Also try different ports on the TV if possible.
However, if the discoloration remains even on the solid test screen, then the issue is most likely with the TV itself, meaning a repair or replacement may be necessary.
Check Video Settings
If the source content looks fine when displayed on other TVs, the next thing to check is your TV’s video settings. Many TVs have options that can affect half of the screen differently than the other.
For example, many TVs offer a “zoom” or “wide” mode that stretches a 4:3 aspect ratio picture to fill a 16:9 screen. This could cause the stretched half to appear discolored. Make sure your TV is set to the proper aspect ratio for the content source.
Also, check that any zoom, crop, or edge distortion features are disabled. These can be found under video, picture, or display settings on your TV.
Check for Physical Damage
Physical damage to a TV can also cause discoloration or dark areas on part of the screen. Check the bezels and frame of the TV for any cracks, dents, or separations that could indicate damage. Also inspect the screen itself for cracks or impacted areas.
Use a flashlight to check the screen at different angles for any abnormalities. Damage is often easier to see when the TV is off versus when content is actively being displayed.
Address LED/LCD Issues
For LED or LCD TVs, screen discoloration usually means there is an issue with the backlighting system.
With LED TVs, it could be LEDs behind part of the screen that have burned out or are malfunctioning. Removing the TV’s back panel to inspect the LED strips could help identify any dead LEDs that need replacement.
For LCD TVs, the backlight is provided by fluorescent lamps called CCFLs. If an individual CCFL tube is having problems, it will affect half of the screen, generally divided vertically.
Testing the CCFLs with a multimeter can validate if one or more tubes need replacement. This requires disassembling the TV, which should only be done by a qualified repair technician if you are not experienced working on LCD components.
Check for Loose Connections
Loose internal cable connections are another common cause of a half-colored screen. Video data cables that have worked loose could affect one side of the image.
Opening up the TV to check that all ribbon cables are seated firmly in their connectors is recommended. Reseating connectors and cables may help get a better connection and resolve discoloration issues.
Address T-Con Board Issues
The T-Con (timing controller) board controls data signaling to the LCD/LED display. If this board is failing, it can manifest as discoloration on part of the screen.
First, check all connections to the T-Con board to make sure they are secure. Also inspect the board itself for any burnt components or physical damage.
If the T-Con board appears faulty, replacement may be required. On some TV models this is an inexpensive repair, while on others replacement boards can be priced higher.
Consider a Panel Replacement
In severe cases where the LEDs, CCFLs, or T-Con board are not the root cause, the LCD or LED panel itself may need replacement due to a manufacturing defect or physical damage.
Panel replacements can be complicated and expensive repairs. On some TV models it may be close to the price of replacing the entire TV. But on other models, panel replacements are more affordable.
Research the panel replacement cost for your specific TV model to determine if it’s a viable option. Replacement panels can often be found online at part supplier websites.
Other Causes
Less likely causes for a half-colored screen include:
- Failing LCD driver – Generates voltages for the row/column pixels.
- Failing power supply – Provides lower than normal voltages.
- Corroded contacts – Buildup on ribbon cable ends.
- Faulty color wheel – If a projection TV with a color wheel.
Extensive electronics testing would be required to validate issues with these components. A technician may be needed for troubleshooting.
Conclusion
Half of your TV screen suddenly looking different than the normal side is likely due to a failed LED/CCFL backlight, T-Con board issue, loose cable, or physical damage in most cases. Thoroughly inspecting the TV and testing components can help identify the root cause.
Replacement of a particular component may resolve the issue cost effectively. But in severe cases where the panel itself is defective, replacement or buying a new TV altogether may be the practical solution.
| Potential Cause | Troubleshooting Steps |
|---|---|
| Source issue | Check connections, cables, try different ports |
| Video settings | Adjust aspect ratio, zoom, crop settings |
| Physical damage | Inspect bezels, frame, screen for cracks |
| LED/LCD backlight | Inspect LED strips, CCFL tubes |
| Loose connections | Reseat all internal cable connections |
| T-Con board | Check connections, test for damage |
| LCD panel | Research replacement cost |
With some troubleshooting and component-level testing, the root cause of a half-colored TV screen can usually be resolved or a cost-effective repair option identified.
