Why the screen on Xiaomi phone is darkening: all the reasons and solutions

Have you noticed that your Xiaomi screen has become dim for no apparent reason? Or the display suddenly goes out even though the battery is still high? This problem occurs on models from the Redmi Note 10 Pro to the flagship Xiaomi 13 Ultra, and its causes can be due to both system settings and hardware malfunctions. In 80% of cases, software failures or incorrect display parameters are to blame, but sometimes a darkening of the screen signals serious damage, such as a lane detachment or matrix degradation.

In this article, we’ll look at all the possible reasons why Xiaomi’s screen may darken or spontaneously turn off, from the banal (automatic brightness feature enabled) to the critical (damage) reasons. OLED-You'll learn how to diagnose the problem yourself, what settings to check first, and when to contact the service center. For convenience, we've compiled a symptom table and prepared step-by-step instructions with a checklist widget.

If your smartphone is still under warranty, do not try to disassemble it yourself - this will void the warranty obligations of Xiaomi. In case of hardware breakdowns (for example, after a fall), it is better to immediately contact the specialists.

1. Automatic brightness control

The most common cause of sudden screen dimming is adaptive brightness, which adjusts the backlight depending on the lighting. On Xiaomi, this feature often works incorrectly: the light sensor can be delayed or react to false signals (for example, reflected light from glasses), as a result, the screen dims even in a well-lit room.

How to check:

• 🔍 Go to Settings. → Display. → Brightness and turn off the slider "Adaptive brightness".
• 🌞 See if the brightness changes as you move the phone from the shadow to the light, and if so, it works, but it's probably contaminated.
• 📱 Set the brightness manually at 50-70% and check if the problem persists.

If the adaptive brightness switched off, the screen stopped dimming, the cause is found. Otherwise, read on.

⚠️ Note: On some Xiaomi models (e.g, POCO F4) Adaptive brightness may conflict with Reading mode (in display settings). Turn off both settings if the screen darkens when opening books or web pages.

2. Battery saving

The Super Battery Saver feature on Xiaomi aggressively reduces the screen brightness to 10-20% when the charge level drops below 15%. Sometimes it works falsely - for example, due to a faulty battery or a failure in the power controller. Also, brightness can be limited in the "Saving Charge" or "Sleeping" modes.

How to turn it off:

• 🔋 Go to Settings. → Battery → Saving modes and deactivate all options.
• 📊 Check your battery life schedule: If your phone shows an inadequate percentage (e.g. 80% at a real 30%), it’s likely that your battery is faulty.
• 🔄 Restart the device – sometimes the power controller “hangs” and incorrectly displays the level of charge.

If the brightness did not recover after the saving switch was turned off, the problem could be battery degradation: On Xiaomi over 2-3 years old, the battery capacity drops by 30-40%, and the system begins to forcely limit performance, including the brightness of the screen.

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To check the actual state of the battery, type in the Phone app code ##4636##, then select Battery Information. Compare health scores to 100% new battery, below 80% need replacement.

3. Failures after firmware update

MIUI updates often bring not only new features but also bugs. For example, after the release of MIUI 14, many Xiaomi 12T and Redmi K50 users complained about spontaneous screen dimming due to errors in the display driver. Similar problems arose after security updates (for example, Google patches for June 2023).

How to fix it:

1. 🔄 Reboot your phone – sometimes it resets temporary GPU errors.
2. 📱 Reset the display settings: Settings → System system → Resetting settings → Resetting display settings.
3. 🔧 Retracement to the previous version MIUI (If the problem appeared after the update. To do this, download the firmware from the official website and scroll through Recovery.

If after resetting the screen stopped darkening, the fault was the software. Otherwise, the reasons may be hardware.

4. Damage to the plume or matrix

Physical damage is one of the most serious causes of screen blackout, and if the phone fell, was pressured (such as in a jeans pocket), or came into contact with moisture, it could be:

• 📱 The display plume is a thin cable that connects the matrix to the motherboard. When the screen is partially cliffed, the screen dims or flickers.
• 🔳 Illumination of the matrix — LED-You see, you see a tape on the edges of the screen, and if you get damaged, you get dark spots or even dimming.
• 🛠️ The display controller is a chip on the board that controls the brightness. When overheated or oxidized, the screen can go out.

How to diagnose:

⚠️ Note: If Xiaomi’s screen darkens after replacing the display in an unofficial service, a non-original module was probably installed.Such matrices often have problems calibrating brightness and color reproduction.Check the labeling on the plume – the original parts have a Xiaomi logo and serial number.

5. Diagnostics by means of test modes

All Xiaomi smartphones have hidden screen tests to help you identify hardware problems without disassembling your phone.

For models on Qualcomm Snapdragon (most Redmi and POCO):

Enter the phone app: ##6484##


Select "Manual Test" → "Display" → check all colors and brightness.

For models on MediaTek (e.g. Redmi 10C):

Enter #36446337##


Go to "Hardware Testing" → "LCD Test."

What to check in test mode:

Checking all colors (red, green, blue, black, white)|A test for broken pixels|Testing of touch response|Lighting test (brightness 0%, 50%, 100%)|Check the light sensor (cover the top of the screen with your hand)-->

If the screen behaves normally in tests but dims normally, it's a software problem, and if the artifacts (strips, flickering) are visible in test mode, the hardware malfunctions.

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Test modes do not check the display plume! If the screen goes out when physically exposed (pressed, tilted), disassembly of the device is required.

Other possible causes

If none of the above points are appropriate, check these factors:

• 🔌 Charger or cable: Non-original accessories can cause voltage drawdowns, causing the phone to limit brightness.Try charging Xiaomi from another power supply.
• 🧲 Magnetic interference: If a powerful magnet is lying next to the phone (such as in a magnetically mounted case), the Hall sensor can falsely trigger and turn off the display.
• 🦠 Viruses or malware: Some apps (especially from third-party sources) can change brightness settings in the background).
• ☀️ Overheating: At temperatures above 45°Xiaomi's C forcefully dimms brightness to reduce CPU load.Make sure the phone doesn't heat up (use CPU Monitor from Google Play).

Rarely, factory defects are also encountered, such as the Xiaomi 11T Pro (released in 2021) batch of backlight controllers that caused the screen to dim after 10 to 15 minutes of operation, in which case only the replacement of the motherboard under warranty helps.

7. What should I do if nothing has worked?

If you’ve tried all the ways, but Xiaomi’s screen still gets darker, follow the algorithm:

1. 📋 Gather evidence: Record a video demonstrating the problem (especially if the screen flickers or goes out when tilted.
2. 🔧 Contact the service: 🛠️ Xiaomi official service - if the phone is warranty (even with mechanical damage, sometimes they go to meet the requirements of the service). 🔨 Unofficial workshops are cheaper, but they're at risk of unskilled repairs.

Evaluate the feasibility of repair:

• Replacement of the matrix: from 5,000 ₽ (on AMOLED — up to 15,000 ₽).

⚠️ Warning: If the wizard suggests "switching the display controller" instead of replacing the plume or the matrix, it's fraud.

Frequent questions