TVs are constantly evolving, and the latest models feature some incredible cutting-edge technologies. Such is the case with televisions that boast High Dynamic Range (HDR) capabilities, which may represent the biggest leap in picture quality since the dawn of HD. But what suddenly makes a TV screen go too dark at random, and how do you fix it?
If your TV screen is too dark — even on full brightness — first check to see if the TV’s ambient light settings are automatically dimming it, then try to modify the brightness and contrast directly in the picture settings menu. Power saver mode can also lead to automatic screen-dimming.
The fixes we’ll discuss in this guide are relatively manageable, and you don’t have to be a TV expert to figure them out. Let’s take a closer look at why this problem occurs and go through the potential solutions, so that you can get that smart TV up and running like it’s new.
How Do TVs Work To Manage Their Own Brightness?
The technologies used in LCD, LED, and OLED TVs are fundamentally different. Interestingly, the differences go further, and various display modes exist, even for movies, soap operas, and animated shows.
For most TV sets, the display mode is always set to a dark mode by default to protect your eyes from unexpected glares.
You’ll find that most TVs have ‘Neutral‘ and ‘Theatrical‘ display modes. That’s the case regardless of the various screen technologies they may have. The Theatrical mode is usually set by default, but you should switch to the Neutral mode to have better picture quality and a clearer vision without hurting your eyes.
Less advanced TV models commonly use a backlit LCD screen, meaning there’s a system behind the panel to shine light on it and make pictures visible.
As it turns out, a backlit panel doesn’t have the best contrast, and the picture quality may be pretty messed up if you’re viewing from certain angles.
SDR and HDR
Over the years, movies and shows were mastered in standard dynamic range (SDR), which is pretty dim, with a peak brightness level capped at 100 nits. The term nit is just a measure of the intensity of visible light.
With modern LCD TVs, however, you can have up to 300 nits when playing SDR content. If the TV is in a room with bright lighting, you can tweak the backlight settings and increase the overall brightness level. That means everything in the picture will be affected, including dark shadows.
But with HDR TVs, everything is different, and just as the name suggests, it gives you a higher dynamic range. If you’re struggling to wrap your head around that, it means there’s a bigger gap between the bright and darker parts of the image. In fact, HDR allows bright highlights of as much as 1,000 nits or more, depending on what your TV can handle.
If the sun is shining through the woods, for example, an HDR TV will display it in a way it really pops against the shady background.
The average brightness of an HDR image should theoretically be similar to what you’d have with SDR, although it can vary with the kind of movie you’re watching and how it’s graded.
You should note that many TV models commonly have the contrast and backlight levels set to the highest value in HDR mode, meaning you can’t adjust them further in a brightly lit room.
What Causes a Dark TV Screen?
Generally, your TV screen will grow dark if it has poor reflection handling and low HDR performance, especially in a brightly-lit room.
To fully understand what causes the TV dark screen issue, you must have a general idea of how screen brightness works. Without too much technobabble, brightness basically implies a TV’s luminance level.
A TV set with a higher luminance level can make pictures appear brighter, which comes in handy in an already-bright room. It can also make small highlights stand out if you’re watching in HDR.
If you can adjust the backlight setting on your TV, which some brands alternatively call brightness, it doesn’t affect the picture quality. You can set it to whichever level you prefer.
Now that you understand how brightness works, these are the reasons you may be seeing a dark screen on your TV:
Poor Reflection Handling
Reflection handling refers to how your TV absorbs and reflects the light falling on its screen from the surroundings. A TV with poor reflection handling capabilities will make the picture dim, and the screen grows dark if you place the TV in a bright room.
If there’s sunlight coming in from the windows, you’ll find it difficult or even impossible to see the screen properly. If your daily use applies to this scenario, you should get a TV with a high peak brightness and excellent reflection handling so that you can still see vivid images.
Low HDR Performance
It’s also common that the TV screen grows dark if you’re watching in HDR. The issue still has to do with the brightness, since your TV needs to have a high brightness level for an authentic HDR experience. It’s the only way picture highlights will pop out appropriately.
Unfortunately, some TV models are known to hide their HDR failings by darkening images anyhow. The light output for some 4K HDR TVs is often similar to what you’d expect in standard non-HDR TVs.
While this is a common downside of cheaper TVs, it can also happen with some midrange and high-end models that skimp on brightness.
TVs that can’t produce bright highlights at specified levels are usually designed to perform tone-mapping, the process through which they fit content to their capabilities.
For example, a low-end TV with a 350-nit brightness can’t highlight a scene at 1,000 nits. To compensate, it will simply adjust the scene so the highlight is 350 nits, the maximum it can handle.
In effect, the TV has to clip the bright highlights to maintain the average brightness of the scene. While the picture won’t darken much, certain highlights will be slightly blown out.
Alternatively, engineers also design some models to lower the average brightness of the scene, keeping the details in the highlights but making the original image darker than it was originally mastered.
If your TV lowers the average brightness for some scenes, you’ll have trouble watching shows and movies in an adequately lit room, with the screen appearing darker.
As it turns out, just because your TV can work with HDR signals doesn’t mean it can produce HDR effectively.
Why Is Your TV So Dark on Full Brightness?
If the pictures on your HDR TV grow too dark when you have the highest brightness setting, clearly something isn’t right. After all, isn’t HDR all about brightness? Well, it boils down to a bit more than that, and these are the reasons your TV can be so dark on full brightness:
Ambient Light Detection Lowers Brightness
Modern smart TVs have sensors that measure the light in the surroundings and adjust the screen brightness accordingly. During the day, or if you’re in a brightly lit room, the sensors direct your TV to turn down the brightness and reduce glare.
At night, or in a dimly lit room, the sensors have your TV increase the brightness so you can have the best possible resolution.
For instance, if you’re using the latest Samsung Smart TVs, they come with the Eco Sensor feature.
The Eco Sensor intelligently adapts your TV’s picture according to the light intensity in the room, often reducing the brightness in a well-lit room to minimize power consumption. You can disable it by changing the backlight setting of the Picture menu while the Eco Sensor is running.
Cinema Mode Is Too Dark for Daytime Viewing
TV guides usually say you should put your TV in the ‘Cinema‘ or ‘Movie‘ mode to have the best picture experience. While that’s true, changing the picture preset to Cinema mode makes images too dim in a brightly lit room, and the screen appears darker.
TV experts confirm that such a preset is specifically optimized for dark room viewing and will otherwise mess up the situation in bright conditions. Some TVs have the ‘Cinema Home’ mode, which is brighter than the regular Cinema Mode.
Power Saving Mode Lowers Brightness
Some TV brands and models have the power-saving mode parameters set to high by default. This will reduce the screen brightness, causing the dark screen issue. Most of the time, however, you could’ve activated the power-saving mode by mistake.
Wrong Picture Presets Make the Screen Dark
Your TV screen can be dark even if no one has messed around with the brightness settings. Sometimes, it’s just because of incorrect picture presets like sharpness, color, and tint.
It’s always a good idea to check your manual and tweak these configurations to your taste. You may have to try different combinations before finding what works best for you.
Backlight Could Be Faulty
Unless you’re using an OLED TV, any other model that uses an LCD screen also has a backlight to illuminate the images on the screen.
The backlight controls your TV’s brightness, and the screen will inevitably become dark if the backlight malfunctions. Some parts of the screen or the entire panel suddenly become dark.
While OLED TVs can’t have backlight issues, they experience a phenomenon called burn-in. The pixels in a significant portion of the screen can fail permanently, leading to a static, dark image.
Weak Signal Strength
Your TV screen can also become dark if there’s weak signal strength or if the signal quality of the external device you’ve connected is poor. This can be due to damaged cables, faulty antennas, or wrong connections.
Why Is Your TV Screen Half Dark?
The main reasons your TV screen can be half dark include a faulty or loose HDMI cable, a defective backlight system, and interference from external devices. It can also be that the video driver circuit is damaged and needs to be replaced.
How Do You Fix a Dim TV Screen?
Fixing a TV screen that’s too dim often involves doing a few simple configurations, and here’s how to do it:
Disable the Ambient Light Detection Feature
Disabling the ambient light detection feature will make your screen consistent, irrespective of the movie scenes and changes in the surrounding light conditions. As highlighted before, the ambient light detection feature is called Eco Sensor in Samsung smart TVs.
Here’s how to disable the Eco Sensor in older TV models (those made before 2016):
- Turn on your TV and navigate to Settings.
- Tap the ‘Eco Solution‘ option, then select ‘Eco Sensor.’
- Turn off the Eco Sensor and check if it fixes the issue.
For newer Samsung TVs, here’s how to disable the ambient light detection feature:
- Go to Settings, then scroll down to General.
- Select ‘Ambient Light Detection‘ and move the slider to the ‘OFF‘ position.
Turn Up the Brightness
Since the brightness setting determines how much light your TV emits, one quick fix for the dark screen involves adjusting the brightness to a higher level.
On your TV remote, press the ‘Settings‘ button, then navigate to ‘Picture.’ Select ‘Advanced‘ (or ‘Expert Settings‘) in Samsung smart TVs, then choose ‘Brightness.’ Adjust the brightness until you get the best viewing experience.
And if your room is bathed adequately in natural light, you’ll need more brightness. The closer you are to 100, the better your image outlook will be relative to the surrounding.
Turn Up the Backlight
Turn up the Backlight setting in combination with the brightness to get rid of the dark screen. While most TVs won’t allow you to adjust the backlight level beyond a certain threshold in HDR mode, some brands usually don’t cap it too low.
For Sony TV, this setting is usually labeled as ‘Brightness,’ and you should configure it accordingly.
Adjust the Contrast Level
Contrast means the ratio between the brightest and darkest spots on your screen. Too much contrast blends colors, creating an overall dark appearance.
Go to Settings, select ‘Picture,’ and then ‘Advanced‘ or ‘Expert Settings.’ Adjust the contrast level until you’ve got the best view. You’ll have to push to a very high contrast level if you’re in a dark room.
Turn Off Black Tone
The black tone setting usually makes back spots on your TV appear darker. But it could also make gray areas appear black, making you lose a lot of detail. Here’s how to disable the black tone on your TV:
- Press ‘Settings‘ on your TV remote and go to ‘Picture.’
- Select ‘Advanced‘ and navigate to Black Tone, then turn it ‘OFF.’
Disable Power Saver Mode
The ‘Energy Saving,’ ‘Eco,’ or ‘Power Saving‘ modes often reduces the TV’s brightness level to prevent overheating and too much power consumption. Turning it off will lead to a significant improvement in your viewing experience. Here’s how to disable it:
- Press the ‘Home‘ button on your TV remote.
- Navigate to Settings and choose ‘General.’
- Select ‘Power Saving‘ mode and turn it off. In Samsung TVs, you first select ‘Eco Solution,’ then go to Power Saving mode.
Change Picture Presets
Changing your picture presets to normal viewing mode will often counter the effects of ambient light settings and get rid of the dark screen. Some TVs have different names for this, such as Standard, Cinema Home, Normal, etc.
You can also try relocating your TV if you’ve already tweaked the picture presets but aren’t noticing any significant change.
Reduce Gamma Setting
High-end TVs like Samsung have a setting called Gamma, whose value is typically 2.2 by default. To make your pictures appear brighter and eliminate the dark screen issue, you can reduce the Gamma points to 2.0 or slightly lower.
Revert to SDR Mode
Since HDR only improves dark-room viewing, you can watch your shows in SDR. Open your TV’s Menu, navigate to the General settings, go to Display, and turn off HDR. You can always switch back to HDR when watching movies in a dark room and want the full effect.
Set Pulse Width Modulation to 100
Pulse Width Modulation (PWM) is another setting that automatically regulates the brightness level of your TV according to movie scenes. But the PWM settings can make your TV appear too dark, and you’ll have to change them by putting the TV in Service Mode. Here’s how to change the PWM setting in a Samsung TV:
- With your TV off, press Mute, 1, 8, 2, and Power — in that order. The Service Menu will appear shortly.
- Select ‘SVC,’ then go to ‘Other Settings.’
- Choose ‘CAL Data Restore,’ then press ‘Return‘ to navigate back to the first menu.
- Scroll down to Advanced and press ‘0‘ four times to display extra menu options.
- Go to Picture_2D, open SubSetting and run the PWM settings up to 100.
Your TV will now maintain its brightness level irrespective of the movie scene.
Reset the TV
Restoring your TV’s settings to default often clears bugs and other software errors that may cause the screen to grow overly dark. Here’s how to reset your TV:
- Press the ‘Settings‘ button on your remote and go to General.
- Select ‘Reset‘ and confirm your choice.
Some TVs require you to enter a PIN, and you can key in the default one, which is 0000. But if you’d changed it earlier, be sure to enter the correct PIN. Since the procedure may vary depending on your TV model, check your manual for the exact instructions.
Check for Firmware Updates
Your TV needs constant firmware updates to run smoothly and display pictures correctly. You can check the latest software version on your manufacturer’s website and update your TV as follows:
- Press the ‘Settings‘ button on your remote.
- Go to ‘Support,’ or ‘Advanced,’ depending on your TV brand.
- Select ‘Software Update.’ Your TV will automatically install the latest firmware version and reboot once it’s complete.
Seek Professional Technical Help
If all the solutions we’ve discussed don’t work for you, your TV could’ve encountered a severe hardware problem. If there’s been a power surge, for example, it could’ve burned out the capacitors or some other component on the driver board. And if your TV uses an LCD screen, the backlight may be damaged.
You might want to take your TV for professional servicing at your own cost if your warranty is expired. A qualified electronics technician will quickly diagnose the problem, remove the faulty hardware components, and install new replacements, even if it’s the panel itself.
While professional help can be costly, you’ll undoubtedly have your TV up and running like before. Don’t attempt to figure out the problem yourself or repair your TV unless you’re very sure of what you’re doing.