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TV Keeps Dimming (Causes and How to Fix)

As a frustrated owner of a TV that keeps dimming on its own, I know how annoying it can be. After doing some research and trying out some different tips and tricks, I’m here to share what I discovered to be the causes and how to fix this issue. In this blog post, I will explain the different causes of why your TV keeps dimming and the steps you can take to resolve the issue.

Other reasons why your TV keeps dimming include a weak signal, image retention, outdated firmware, and issues with external outputs.

IssuePossible CausesSolutions
Ambient Light DetectionAdjusts backlight brightness based on surroundings.Turn off ambient light detection settings in your TV’s picture settings.
Dynamic ContrastDeepens blacks and whitens bright areas in content.Adjust dynamic contrast settings to low, medium, high, or turn it off.
Weak Signal and Image RetentionStatic elements and prolonged picture display.Manage connections and create specific external input settings for frequently used devices.
Global DimmingCCFLs for backlighting causing entire screen dimming.Update your TV’s firmware or consult a professional if the issue persists.
External InputsPower-saving mode or compatibility issues with connected devices.Check the brightness levels in picture settings and resolve compatibility issues if necessary.
Outdated FirmwareInefficient or outdated firmware affecting hardware.Update your TV’s firmware by downloading from the internet or using a USB.
Broken Lighting PanelsWear and tear or damage to the TV’s backlight.Consult a professional to assess the issue and determine if repair is the best option.

7 Reasons Why TV Keeps Dimming

When your TV keeps dimming, it doesn’t necessarily mean that it needs to be repaired. It may just require you to do a few tweaks in its settings.

To help you troubleshoot, here are a few things to look into.

Ambient Light Detection

This is also called an eco-sensor for older television sets. To lower the overall cost, this feature is added to the TV to adjust backlight brightness according to the surroundings.

If your ambient light detection is turned on, being in a well-lit room will surely dim your TV screen. Moreover, you’ll experience more dimming and subsequent brightening if you have inconsistent lighting.

Dynamic Contrast

Another feature that highly affects your screen display is dynamic contrast. This works to give you a crisp picture and is highly dependent on the material you’re watching.

It can come in different intensity levels from low to high. You can also opt-out of using it entirely. Choosing a high level makes your display deepen the blacks and whiten the bright areas more.

It’s no surprise that if you watch content with many dark scenes, then you’ll likely encounter frequent screen dimming.

Weak Signal and Image Retention

Have you ever experienced getting a weak signal? For older TV models, maybe you’ve noticed that even after that incident you can still see outlines of the previous images.

Static elements and prolonged picture display can cause image retention

As such, TVs are now armed with additional features that dim screens to avoid these scenarios.

Global Dimming

TVs have display panel processors. Their function is to run things smoother and give a high-quality picture. They’re also responsible for lowering the power supply to the backlight when screen dimming is necessary.

However, some TVs that employ Cold Cathode Fluorescent Lamps (CCFLs) for backlighting may experience dimming of the entire screen instead of an isolated area. This is termed global dimming.

External Inputs

Connecting your TV to external devices like personal computers, game consoles, and disc players also affects your screen display.

For instance, when you connect to a device that is set on power-saving mode, you can expect dimming of your TV screen. This may require you to change brightness levels in your picture settings.

While connecting, you may also encounter adapter issues and power supply problems that can lead to display changes.

Outdated Firmware

Your TV’s firmware holds data, applications, settings, and programs that drive the hardware to function properly. But this can become outdated.

It needs to be upgraded, especially when constantly using online applications. Plus, this can help improve efficiency and resolve compatibility issues with external inputs.

Broken Lighting Panels

Most dimming issues arise from your TV’s settings. Essential to all of this is your backlight. As it experiences regular wear and tear, it’s no surprise that one or a few bulbs may get busted.

Therefore, no matter what kind of changes you try to implement, they won’t work unless this problem is resolved.

How to Fix a TV That Keeps Dimming?

Now that you know why your TV keeps dimming, it’s time to discuss how to prevent this from happening.

First, explore and locate your TV settings. These are typically located under Picture, Advanced, or Expert settings. Then, do the following:

  • Turn off your ambient light detection settings.
  • Adjust dynamic contrast settings. Your choices include low, medium, or high, and another option for turning it off.
  • Manage connections. Create specific external input settings for frequently used devices.
  • Update your TV’s firmware. You can do this by downloading straight from the internet or through a USB.
  • Turn off the automatic picture mode setting.
  • Manually adjust picture settings like color balance, contrast, and brightness levels to your liking.
  • Reset to factory settings if necessary.

If doing the above-mentioned actions doesn’t work, then you may have a broken lighting panel. Here, it’ll be time to consult a professional on this matter. 

Apart from doing the actual work, they may give you an idea of costs to help you decide if repair is your best option.


TVs make use of features that boost picture quality and provide energy savings. These include ambient light detection and dynamic contrast, which automatically adjust your screen displays.

However, personal preferences vary. Screens that frequently dim and brighten due to auto settings can be bothersome. In such cases, it’s best to turn off these settings.

Enjoy your viewing experience by manually adjusting your TV’s contrast, brightness, and color balances. If that doesn’t solve your problem, you can check your external inputs or update your TV’s firmware.

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