Why Xiaomi’s Fingerprint Doesn’t Work and How to Fix It

Modern smartphones Xiaomi, Redmi and Poco are equipped with advanced biometric protection systems, which are designed to provide instant access to data and payment services. However, users often face a situation where the scanner stops responding to touches or starts to mistakenly reject previously stored fingerprints.This causes panic, especially if alternative login methods such as a pattern lock or a graphical key are used to make the scanner more responsive. PIN-code, not configured or forgotten.

The problem can be either software-related errors in the MIUI or HyperOS shell, or hardware-based problems that indicate physical damage to the module, and in most cases, the failure can be fixed without going to the service center, by performing a series of sequential diagnostic steps, and it is important not to panic and methodically check the security settings.

In this article, we will discuss the main reasons for biometric failure and propose effective solution algorithms, you will learn how to recalibrate the sensor correctly, whether to remove old prints and in which situations you need to completely reset the settings.

The main causes of failures in the work of biometrics

The first step is to understand it, and users often blame the smartphone itself for the failure, even though it's caused by trivial external factors. Pollution of the scanner surface with greasy traces, dust, or moisture is the most common reason why the sensor stops reading the pattern. Even a thin film of fat can disrupt contact between the finger and the sensor.

The second important aspect is the condition of the finger itself: dry skin, microcracks, calluses or dirt under the nails significantly reduce the quality of the reading. Xiaomi algorithms are sensitive to changes in skin relief. If you have recently been engaged in manual labor or, conversely, have been in water for a long time, biometrics may temporarily not work.

Software conflicts also play a role: After updating the operating system or installing security updates, errors may occur in the service android.hardware.biometrics. Sometimes third-party applications that have access to security functions block the scanner from working correctly.

⚠️ Attention: If the phone has recently fallen or been hit, the problem may be due to the scanner plume moving away from the motherboard.

For a quick diagnosis, try to wipe the scanner area with a soft cloth and wash your hands with soap and dry them thoroughly. If that doesn't help, go to software settings.

Primary diagnostics and data cleaning of the scanner

If external factors are excluded, it is necessary to clean up stored biometric data. The accumulation of errors in the fingerprint database can lead to false positives or complete disregard of touches. It is recommended to remove all saved fingers and register them again, with special care.

To do this, go to the Settings menu, select the Passwords and Security section, and then Unlock by fingerprint. In the list of saved fingerprints, click on each and select the delete option. After clearing the list, try adding the fingerprint again, noting how the phone vibrates when you read successfully.

When you re-register, take your time. MIUI allows you to add additional areas of the same finger. Use this feature to create a more complete profile. If the scanner is built into the on button, touch it with the whole pad of your finger, not just the edge. If the scanner is underscreen, apply your finger tightly and hold it for 1-2 seconds until you vibrate.

It is important to note that when you add a new fingerprint, the system may request input. PIN-This is the standard Android security procedure, which ensures that only the owner of the device has access to the biometrics. If you don't remember the password, it will be impossible to restore access to the settings menu without resetting the data.

Suggestions of sensitivity and additional parameters

Smartphones with subscreen scanners (optical or ultrasonic) often underestimate the importance of sensitivity calibration. Depending on the model, such as the Xiaomi 13 or Poco F5, the settings may differ. To improve the readability of the shell, there is a sensitivity enhancement feature, especially useful when using protective glasses.

Go to Settings → Additional → Fingerprint Scanner. You can find the Sensation Enhance Sense Switch here. Activating this option makes the screen shine brighter in the scanner area and increases the time of the sensor survey, which helps if you use thick tempered glass that distorts the signal.

Also worth noting is the "Show fingerprint icon" feature, which, although it doesn't directly affect how the sensor works, the visual cue helps you position your finger more accurately. Some firmware versions offer the "Improved Recognition" option, which uses machine learning algorithms to adapt to skin changes.

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When registering a fingerprint, change the angle of the finger for each new touch, which will create a three-dimensional model and increase the reliability of unlocking.

Resetting and system update

If the fingerprint manipulations fail, there may be software errors in the system, resetting the biometrics or the entire system can be a radical but effective solution, and before starting the procedure, make sure you remember your Mi Account and the screen unlock password.

Try resetting special features. Sometimes accessibility services conflict with scanner drivers. Go to Settings → Advanced Settings → Special features and disable all active services. Reboot the device and check the sensor.

Check for system updates. Xiaomi engineers regularly release patches that fix bugs in the biometric modules. Go to Settings → About the phone and click on the MIUI/HyperOS version. If an update is available, install it.

⚠️ Warning: Full reset to factory settings (Wipe Data) will delete all photos, contacts and applications. be sure to back up the data to the Mi Cloud cloud or to your computer before this step.

To do a full reset, use the Recovery menu. Turn off your phone, then press Volume+ and Power at the same time. From the menu that appears, select Wipe Data → Wipe All Data. Once the process is complete, the phone will return to the state out of the box.

Hardware problems and diagnostics of the module

When software methods are exhausted, you have to consider a physical breakdown: fingerprint scanners, especially those built into the power button, are subject to mechanical wear, and constant pressure and micro-impacts can damage the internal machinery or the plume.

In smartphones with subscreen scanners, the cause could be detachment of the adhesive layer between the display and the sensor, or damage to the display module itself after a fall. Even if the screen is intact visually, the internal structure could be disrupted, which affects the passage of the light signal (in optical scanners).

You can use an engineering menu or Google Play app for self-diagnosis, such as Test Hardware or Device Info HW, to check the sensor's status on the motherboard, and if the app says "Sensor not found" or "Disconnected," the problem is exactly "hardware."

• 🔌 Trail Retraction: A frequent problem after falls, requires disassembly and reconnection of the connector.
• 💧 Contact oxidation: Moisture intrusion could cause scanner contacts to corrosion.
• 🔥 Controller failure: A rare but possible situation requiring a complete module replacement.

If you don't have the skills to repair electronics, don't try to disassemble the phone yourself. Breaking the factory seal will take away your warranty. You'd better go to an authorized service center for professional diagnostics.

Alternative methods of protection and unlocking

While you’re waiting for a repair or looking for a solution, it’s important to ensure data security and easy access to the device. Xiaomi offers several alternative authorization methods that may be even more convenient than a fingerprint in certain situations.

Face ID works fast enough on most of the brand's models, and while it's less secure than a finger biometric, it's good enough for everyday use, you can set it up in the same password and security menu, and the algorithm takes into account lighting and the angle of head rotation.

We should not forget about the classics either. PIN-Set up complex but memorable code, and in the security settings, you can only enable the "Show notifications on locked screen" option after you enter your password, which will increase privacy.

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Using a combination of security techniques (e.g. Face ID + PIN) provides maximum security even when the fingerprint scanner is not working.

Also consider using smart locks, which lets you keep your phone unlocked when it’s in a trusted location (at home) or connected to your Mi Band smartwatch, which will reduce the need for frequent authorization.