How to turn off the fingerprint plume on Xiaomi

Owners of modern Xiaomi smartphones often encounter visual artifacts in the work of biometric protection. One of the most annoying effects is the so-called “stick” or sticking image when unlocking the device, a phenomenon that not only reduces the aesthetic appeal of the interface, but can indicate software failures in the security module TEE (Trusted Execution Environment).

The problem is different, from the slow disappearance of the scan animation to the complete freeze of the indicator on the lock screen. In some cases, the system perceives a single touch as a series of continuous inputs, which causes chaotic behavior of the interface. Understanding the nature of this defect is the first step to its successful elimination without loss of data.

In this article, we will explore all the possible causes of the visual artifacts of the fingerprint scanner on the shell of MIUI and HyperOS. You will learn how to programmatically disable or reconfigure the sensitivity of the sensor, clear the cache of the security system and what hidden settings can affect the speed of rendering animations. Sometimes the solution lies in the banal cleaning of the surface, and sometimes requires a deep reconfiguration of the system.

Causes of the plume and artifacts of the scanner

The appearance of a visual “trail” or delay in the response of a fingerprint scanner on Xiaomi devices is rarely accidental. Most often, the root of the problem lies in the conflict between the software algorithms for processing biometric data and the operating system graphics engine. When the processor is busy with background tasks, rendering the unlock animation can slow down, creating the illusion of sticking or plume.

Another common cause is wear and/or contamination of the sensor itself. On models with an optical-type underscreen scanner, any stain of fat or micro-scratch on the protective glass can scatter light, resulting in incorrect reading and repeated scanning attempts. The system tries to compensate for the poor signal by prolonging the indicator's operating time, which is visually perceived as a plume.

Modified themes often contain unoptimized graphic elements that conflict with standard SystemUI services. If you recently changed the theme or installed a new icon package, the problem may lie in the incompatibility of resources.

• 🔍 Process conflict: Overload of RAM prevents timely rendering of unlock animation.
• 💧 Sensor pollution: Fat traces or moisture distort the optical scanner signal.
• 🎨 Third-party themes: Unofficial themes may contain errors in animation code.

⚠️ Warning: If the plume is accompanied by heating of the lower part of the screen or rapid battery discharge, this may indicate a hardware malfunction of the scanner controller, requiring diagnosis at the service center.

Basic setup and removal of old prints

The first and most effective step in eliminating artifacts is to completely re-register biometric data. Old, partially read prints can create conflict with new data, causing processing delays. Xiaomi's security system stores several variations of your finger, and if one of them is damaged, it affects the overall operation of the module.

To start, you need to go to the settings menu. The path usually looks like: Settings → passwords and security → fingerprints. Here you need to log in with your current unlock password, which is a security measure that prevents unauthorized access to biometric data.

Remove all the fingerprints you have saved, even those you think work perfectly, and after cleaning the list, recreate the new prints, paying special attention to the edges of your finger. When registering, try to touch the sensor with different parts of the pad so that the system builds the most accurate possible sensor. 3D-model.

It is important to note that when creating a new fingerprint, you should not press your finger too hard. Optimal pressure ensures that the skin pattern is read better without distortion. If you use a protective glass, make sure that it is compatible with optical scanners, as thick glass can reduce sensitivity and provoke the appearance of plumes.

Cleaning up security cache and system data

The accumulation of temporary files and errors in the cache of system applications is a common cause of biometrics malfunctioning. Xiaomi Security Center stores logs of login attempts and temporary graphics. When this volume becomes too large or files are corrupted, the interface begins to “glue” by displaying plumes and delays.

To do a deep cleanup, go to Settings → Apps → All Apps. In the list, find the Security or Security app. Click on it and select Memory (or Storage). Here you click Clear and select Clear Cache. In some cases, if the problem persists, you can try Clear All Data, but this will reset antivirus settings and call filtering.

The path for manual cleaning through ADB (for advanced users):


adb shell pm clear com.miui.securitycenter




adb shell pm clear com.android.keyguard

Once the cache is cleared, make sure to reboot the device. A normal screen shutdown is not enough; a full cycle of Power → Restart restart is required, allowing the operating system to re-initialize the fingerprint scanner drivers without the burden of old bugs.

• 🗑️ Cache Clearing: Deletes temporary graphic files causing artifacts.
• 🔄 Reboot Services: Forced Reboot Updates Biometrics Drivers.
• 🛡️ Resetting security settings: Returns protection settings to factory values.

⚠️ Warning: Cleaning up the security app’s “All Data” will remove the saved blacklist numbers and antivirus settings. you’ll have to manually configure them again.

Customization of animations and the MIUI/HyperOS interface

Visual plume is often a consequence of the animation engine, not the scanner itself. In the shells of MIUI and the new HyperOS, many parameters are responsible for smooth transitions. If the phone is under-resourced, the unlock animation may not have time to load, leaving traces of previous frames on the screen.

Try rescaling the animations in the developer menu. To activate this menu, you need to quickly click on the MIUI version number in the About Phone section. After activation, go to Advanced Settings → For developers. Find the options "Window animation scale", "Scale of transition animations" and "Duration scale of the animator."

Set a 0.5x or even a No Animation for all three, which makes the interface more twitchy, but eliminates the possibility of plumes being created because of rendering delays, and if the problem disappeared after that, it was the performance of the graphics accelerator.

It is also worth checking the settings of a specific theme. Some elements, such as the Press Effect or the Live Wallpaper, may conflict with the scanner area. Switching to the classic Standard theme will help diagnose a software conflict.

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Use Productivity or No Sound mode in the side menu – they often turn off unnecessary visuals, which can temporarily remove the scanner plume.

Hardware factors and protective coatings

The physical condition of the screen and the sensor cannot be ignored. Underscreen scanners in Xiaomi smartphones (especially in the Mi, Redmi Note and Xiaomi series) work on the principle of optical reading. Any barrier between the finger and the matrix affects the signal quality. Even a high-quality protective glass with a thickness of more than 0.3 mm can create a scattering effect, which the system interprets as movement or plume.

If you have recently put on a new glass or film, try removing it and checking the scanner on a holoscope screen, often by replacing the accessory with a thinner or specialized one (labeled "Fingerprint Friendly"). It is also important to check for air bubbles or dust under the glass in the scanner area.

When the body is hot (playing or charging), optical sensors can produce increased noise, leading to false positives and visual artifacts. Let the device cool down and check if the problem persists in a cold state.

• 📱 Glass thickness: Glass thicker than 0.33 mm often blocks part of the scanner signal.
• 🌡️ Temperature: Heating the matrix increases the level of digital noise.
• 🧼 Surface cleanliness: Fat film works like a lens, distorting light.

Diagnostics through engineering menu and tests

For deep diagnostics, you can use built-in hardware tests. In the dialer, type the code ##6484## or ##4636##. This will open the CIT (Customer Interface Test) engineering menu. Here, select the item associated with Fingerprint or Touch.

In the test mode, you can see exactly how the system reads the touch, and if you touch it once, it detects multiple inputs or coordinates that are "shaking," it indicates a problem with the touchscreen calibration in the lower zone, not the fingerprint scanner itself, and you may need to calibrate the touchscreen through the same engineering menu.

If the tests show unstable work but the software methods don't help, you may need to reset to factory settings.Be sure to back up your data via MIUI Cloud or locally on your PC before doing so.Reset will delete all user data and return the drivers to their original state.

⚠️ Warning: Entering the engineering menu and changing unknown settings can cause the phone to run unstable, change only the settings you are sure of, or simply use the testing mode without saving the changes.

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If the scanner works perfectly in the engineering test (CIT), and the system is glitzy, the problem is 100% software (theme, cache, application conflict).

Frequently Asked Questions (FAQ)