How to Fix Xiaomi Poco C81 Pro With Random Screen Dimming

If your Xiaomi Poco C81 Pro screen keeps dimming by itself, the phone may be changing brightness because of a display setting, battery mode, heat, app behavior, or the ambient light sensor.

Random screen dimming does not always mean the display is damaged. In many cases, it comes from Auto brightness, Reading mode, Battery Saver, scheduled display settings, or an app that forces lower brightness while video, gaming, reading, or navigation is active.

Start with the simple settings first. Most screen dimming problems can be fixed without resetting the phone.

Quick answer

To fix a Xiaomi Poco C81 Pro with random screen dimming, go to Settings > Display & brightness and turn off Auto brightness. Then check Reading mode, Battery Saver, Dark mode, and any scheduled display settings.

If the screen still dims randomly, restart the phone, update HyperOS or MIUI, check app-specific brightness behavior, clean the light sensor area, and test the phone in Safe mode.

Xiaomi Poco C81 Pro random screen dimming diagnostic table

Symptom	Likely cause	What to check first
Screen dims when moving between rooms	Auto brightness or light sensor	Settings > Display & brightness
Screen looks yellow or dull	Reading mode	Display & brightness > Reading mode
Screen dims when battery is low	Battery Saver	Settings > Battery
Screen dims while gaming or watching videos	App or Game Turbo setting	App settings and Game Turbo
Screen dims outdoors	Auto brightness or sunlight adjustment	Brightness and display settings
Screen dims after a few seconds	Screen timeout or battery setting	Lock screen and display settings
Screen dims after update	Software bug or display profile reset	Update phone and apps
Screen dims when phone feels hot	Thermal protection	Let the phone cool down
Screen dims only in one app	App brightness control	App permissions and settings
Screen keeps dimming after all fixes	Sensor, display, or system issue	Xiaomi service check

Why your Xiaomi Poco C81 Pro screen keeps dimming

Your Xiaomi Poco C81 Pro may dim the screen randomly because the phone is trying to adjust brightness based on your surroundings, battery level, temperature, or active app.

The most common causes are:

Auto brightness is reacting too aggressively
Reading mode is changing the display tone
Battery Saver is lowering brightness
The phone is overheating
A video, game, or reading app is controlling brightness
The ambient light sensor is blocked
A software update changed display behavior
A third-party app is interfering with brightness
Screen timeout settings are too short
There may be a display or sensor problem

Use the fixes below in order.

1. Turn off Auto brightness

Auto brightness is the first setting to check. It uses the phone’s light sensor to adjust the screen based on your surroundings. If the sensor misreads the room, the screen may dim even when you do not want it to.

1. Open Settings.
2. Tap Display & brightness.
3. Find Auto brightness.
4. Turn it off.
5. Move the brightness slider to a comfortable level.
6. Use the phone normally for a few minutes.

If the screen stops dimming, Auto brightness was likely the cause.

This is the best first fix if your Xiaomi Poco C81 Pro dims when you walk indoors, sit near a window, cover the top of the screen, or move between bright and dark areas.

2. Clean the light sensor area

The ambient light sensor helps the phone decide how bright the screen should be. If the sensor is covered by dust, a thick screen protector, a case edge, or oil from your fingers, brightness changes can become inaccurate.

The sensor is usually near the top of the display, close to the front camera or earpiece area.

1. Remove the phone case.
2. Wipe the top part of the screen with a clean microfiber cloth.
3. Check if the screen protector is covering the sensor area.
4. Remove any dirt, moisture, or smudges near the front camera.
5. Turn the screen on and test brightness again.

Do not use sharp tools near the earpiece or front camera area. A simple wipe is enough for this check.

If the screen protector is poorly aligned, replace it with one made for the exact Poco C81 Pro model.

3. Turn off Reading mode

Reading mode can make the screen look warmer, softer, or less bright. It is useful at night, but it can feel like random dimming if it turns on automatically.

1. Open Settings.
2. Tap Display & brightness.
3. Tap Reading mode.
4. Turn Reading mode off.
5. Check if there is a schedule enabled.
6. Disable any custom schedule or night reading setting.

Also open the Control Center by swiping down from the top-right side of the screen. If the Reading mode tile is active, tap it to turn it off.

This fix is especially useful if the screen gets dimmer or yellowish at night.

4. Check Battery Saver settings

Battery Saver can reduce brightness, limit background activity, and change performance behavior to save power. If your Poco C81 Pro dims when the battery drops below a certain percentage, Battery Saver may be turning on automatically.

1. Open Settings.
2. Tap Battery.
3. Turn off Battery Saver.
4. Turn off Ultra Battery Saver if enabled.
5. Check if Battery Saver is scheduled.
6. Disable automatic Battery Saver activation temporarily.

After turning it off, use the phone until the battery drops below the level where dimming usually starts. If the problem stops, Battery Saver was likely lowering the brightness.

You can still use Battery Saver later, but keep manual brightness higher if you need better visibility.

5. Disable scheduled Dark mode and display changes

Dark mode does not usually lower brightness by itself, but some users feel the screen looks dimmer when Dark mode, Reading mode, or scheduled display settings turn on together.

1. Open Settings.
2. Tap Display & brightness.
3. Tap Dark mode.
4. Turn off any schedule.
5. Go back to Display & brightness.
6. Check Reading mode, Color scheme, or similar display options.
7. Disable scheduled display changes temporarily.

Test the phone during the time when dimming usually happens. If it happens mostly at night, a schedule is probably involved.

This is a good fix if the screen dims at the same time every evening.

6. Check app-specific brightness settings

Some apps can control brightness while they are open. Video players, eBook apps, camera apps, navigation apps, games, and streaming apps may use their own brightness slider.

Check the apps where the dimming happens most often.

1. Open the app where the screen dims.
2. Look for display, playback, reader, or brightness settings.
3. Raise the app’s internal brightness slider if it has one.
4. Turn off night mode, eye comfort mode, reader mode, or battery saving inside the app.
5. Close and reopen the app.

If the screen only dims in one app, the phone display is probably fine. The app is likely applying its own brightness or comfort setting.

For games, also check Game Turbo or performance tools if available.

7. Restart the phone

A restart can clear temporary brightness glitches, stuck app processes, and display behavior that started after a long session.

1. Press and hold the Power button.
2. Tap Restart.
3. Wait for the phone to turn back on.
4. Set brightness manually.
5. Use the phone normally.

This will not delete your photos, apps, messages, or files.

Restarting is worth doing after changing display settings because it gives the system a clean start.

8. Update HyperOS, MIUI, and your apps

If random screen dimming started after a system update or app update, another update may fix it. Display bugs, sensor behavior, and battery management can change after software updates.

To update the phone:

1. Open Settings.
2. Tap About phone.
3. Tap the HyperOS or MIUI version tile.
4. Tap Check for updates.
5. Install any available update.

To update apps:

1. Open the Google Play Store.
2. Tap your profile icon.
3. Tap Manage apps and device.
4. Tap Update all.

Also check Xiaomi’s system app updater if it appears in your settings.

After a major update, give the phone a day of normal use before judging battery and display behavior. Phones sometimes re-optimize apps and background processes after updates.

9. Let the phone cool down

Phones can lower brightness when they get hot. This protects the battery, display, and internal components. It often happens while gaming, using mobile data, recording video, charging, or using the phone in direct sunlight.

Try this:

1. Stop gaming, recording, or streaming.
2. Remove the phone case.
3. Move the phone away from direct sunlight.
4. Unplug the charger.
5. Let the phone rest for 10 to 15 minutes.
6. Turn the screen back on and test brightness.

If the screen only dims when the phone is warm, heat is probably the reason.

To prevent it, avoid using the phone heavily while charging, close unused apps, lower game graphics settings, and keep the phone out of hot places.

10. Test in Safe mode or contact Xiaomi support

If none of the settings fix the issue, test whether a third-party app is causing the dimming. Safe mode starts the phone with only essential system apps.

The exact Safe mode steps can vary, but this usually works on Xiaomi and Poco phones:

1. Press and hold the Power button.
2. Press and hold Power off on the screen.
3. Tap Safe mode if the option appears.
4. Use the phone and check if the screen still dims.
5. Restart the phone to exit Safe mode.

If the screen does not dim in Safe mode, a downloaded app is likely causing the problem. Remove recently installed apps one by one, starting with battery saver apps, screen filter apps, launchers, cleaners, blue light filter apps, and gaming tools.

If the screen still dims in Safe mode, the issue may be related to the display, light sensor, or system software. At that point, back up your data and contact Xiaomi or Poco support.

What not to do

Do not install random “brightness booster” apps. Many of them add overlays, drain battery, or make the display behavior worse.

Do not factory reset the phone as your first fix. Try the 10 steps above before doing anything that removes data.

Do not assume the screen is broken right away. Most random dimming issues come from settings, sensors, heat, or apps.

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