You try to add a fingerprint to your Xiaomi, but the system stubbornly produces a "failed to save a fingerprint" error or the process is interrupted in the middle? This problem occurs on Redmi, Poco and Mi devices regardless of the model — whether it is a budget Redmi Note 12 or Xiaomi's flagship 14 Ultra. In 80% of cases, it is not hardware malfunctions, but software failures or user missteps.
Xiaomi’s fingerprint scanner may not work after a MIUI update, mechanical damage to the screen, or even because of mud under the protective glass. We analyzed hundreds of user complaints on 4PDA, Mi Community and service centers to identify 7 key reasons and give step-by-step solutions. Importantly, if your smartphone hit the water or fell from a height, first check the section on hardware damage — there are separate instructions.
In this article you will find:
- 🔍 Diagnostics of a problem – how to understand whether software is a failure or hardware
- 📱 Step-by-step instructions for different versions MIUI (including HyperOS)
- ⚙️ Hidden settings that help bypass the fingerprint saving error
- 🛠️ What to do if nothing helps – from resetting to replacing the sensor
Common mistakes when adding a print
Before digging deeper, check to see if you’re making any of these mistakes:
- 👆 The wrong position of the finger. The sensor should touch the center part of the pad, not the side or bent. On Xiaomi with ultrasonic scanners (for example, the Mi 11 Ultra), this is critical — the sensor reads 3D-relief, not flat image.
- 🧴 Wet or dirty hands.Sweat, cream, food residues, or even a thin layer of dust on the sensor block reading.Rub your finger and screen with a dry lilaless wipe.
- 📱 Protective film or glass: Cheap air bubble films or thick glass (from 0.5 mm) interfere with the optical sensor.
- ⚡ Battery is dead. If it's under 15 percent, the system can block the addition of fingerprints, which is a safety measure. MIUI.
If you avoid these mistakes, but the problem remains, move on to diagnosis.
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On Xiaomi AMOLED-screens (e.g. Redmi) K50 Pro) the optical fingerprint sensor only works when the display is on. Do not try to add a finger to the screen that is off!
Programmatic reasons: from MIUI to HyperOS
Software is responsible for 65 percent of the cases, and here are the most common scenarios.
- Biometrics service failure: After updating MIUI or resetting, com.android.biometrics may freeze. Symptom: when you add a fingerprint, the process is interrupted by 50-70%.
- Feather conflict: Xiaomi with HyperOS (e.g. Xiaomi 14) sometimes gets a bug when the system requires a password from Mi-account to add a fingerprint, although it has never been set.
- Parental control restrictions: If the device is linked to an account with Family Link or Kids Mode enabled, biometrics may be blocked.
- Viruses or modified software: Installing patches through Magisk or rooting often breaks the sensor.
How to check:
- Go to Settings → Applications → Application Management → All applications.
- Find the Biometrics Service (com.android.biometrics or com.xiaomi.biometric).
- Clear the cache and data, then restart the phone.
Clean up the biometrics cache|Delete all the fingerprints saved|Check for updates MIUI|Shut down. VPN/Proxies (they can block authentication servers)-->
Hidden settings: how to bypass the lock
If standard methods don’t help, try these unobvious tricks:
- Activation through ADB (Adb shell settings put global settings fingerprint_service_enabled 1 This command is forced to turn on the fingerprint service if it was disabled by the system.
- Reset biometrics: Go to Settings → About Phone. Tap 7 times on MIUI to turn on Developer Mode. Go back to Settings → Additional → For Developers. Find Biometric Reset and confirm the action.
- Change region. Some firmware (especially Chinese) only works in the selected region of China or India. Change region to Settings → Additional → Language and region.
A critical feature for Xiaomi with MediaTek processors (Helio G96, Dimensity 9000, etc.): after resetting biometric data through ADB, you need to restart the phone in Fastboot mode and execute the command fastboot erase config, otherwise the settings will not apply.
| Xiaomi model | Type of sensor | Frequent problem | Decision |
|---|---|---|---|
| Redmi Note 10 Pro | Optical (under the screen) | Can't recognize a finger in bright light | Reduce the brightness of the screen by up to 50% |
| Poco F4 GT | Ultrasonic (side) | Sensor's busy error | Clear cache com.qualcomm.biometrics |
| Xiaomi 12T Pro | Optical (2D) | It freezes by 80% when added | Turn off "Adaptive brightness" |
| Redmi 9A | Capacitive (back) | He doesn't respond to touch. | Check the integrity of the sensor plume |
Hardware malfunctions: when you need to service
If none of the software methods worked, the problem could be the hardware.
- 🔧 The sensor does not respond at all - there is no vibration, backlight (on optical scanners), sound signal.
- 💧 The phone fell into the water or was exposed to severe humidity (even if time passed after that).
- 📉 After the fall, artifacts appeared on the screen next to the sensor area (on underscreen scanners).
- ⚡ The device overheats in the sensor area during an attempt to add a fingerprint.
The most vulnerable models:
- Redmi Note 11 Pro+ 5G is a weak sensor plume, often departs when falling.
- Xiaomi Mi 10T Pro – side ultrasonic sensor is sensitive to impacts on the body.
- Poco X3 Pro – cheap capacitive sensor fails when hit by dust.
⚠️ Warning: If you disassembled the phone yourself (for example, to replace the battery), check if you damaged the flexible plume of the sensor. On Xiaomi, it often comes along with the plume of the power button - with careless installation, the contacts can go away.
How to check the hardware serviceability:
- Connect your phone to your PC and execute the command: adb shell dumpsys fingerprint If the answer has the mSensor=null string - the sensor is not determined by the system (a sure sign of breakdown).
- Call Xiaomi and name the error code from the logs (see below).
How to get the fingerprint sensor logs?
Bugs of specific versions of MIUI and HyperOS
Some bugs are tied to specific firmware versions, and here are the ones that are going to be relevant for 2026:
| MIUI/HyperOS version | Models. | Mistake. | Decision |
|---|---|---|---|
| MIUI 14.0.3-14.0.6 | Redmi Note 12, Poco X5 | Error "Failure to save fingerprint (code 5)" | Reverse to MIUI 14.0.2 or upgrade to 14.0.8 |
| HyperOS 1.0.3-1.0.5 | Xiaomi 14, 13T Pro | Requires a password from Mi-account when adding a fingerprint | Reset security settings in Settings → Accounts → Mi-account |
| MIUI 13.0.9 (Global) | Redmi K50i | The sensor only works after restarting. | Disable battery optimization for biometrics service |
If you have firmware in the table, try this solution.
- Check for updates in Settings → About Phone → System Update.
- If there are no updates, install the MIUI beta via Settings → About Phone → MIUI Version → Three-Point Icon → Select the Service Pack.
- For HyperOS, sometimes resetting via Fastboot with data storage helps: fastboot erase userdata (NOT erase all!)
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Before updating your firmware via Fastboot, always check the compatibility of the version with your model on the MIUI Downloads website. The wrong firmware can completely disable the sensor!
Alternative methods of unlocking
If the fingerprint is not added, but the phone needs to be unlocked, use these workarounds:
- 🔐 Smart Lock: Set up automatic unlocking on a Bluetooth device (such as a smartwatch) or geolocation.
- 📍 Face recognition is included in the settings → Lock screen → Facial recognition works even when the fingerprint sensor is faulty.
- 🔑 Password/pattern lock. Set up a backup unlock method in Settings → Password and security → Unlocking methods.
- 🤖 Voice unlocking (only for the MIUI 14+). Set up in Settings → Voice assistant → Voice unlocking.
For corporate users: If the phone is tied to Android Enterprise or Knox, the administrator can block biometrics through policies. IT-department.
⚠️ Note: On Xiaomi with HyperOS, do not turn off the main password when using facial recognition (PIN/The system requires that it be entered once in a 72 security for hours and without it you could lose access to your phone!
When exactly you need to bring to the service
There are 3 absolute indicators that the sensor needs repair:
- Physical damage: cracks on the screen in the scanner area, dents on the body (for side sensors), traces of oxidation under the back cover.
- Lack of response: The sensor does not glow, vibrate, or make sounds when touched (check in a dark room for optical scanners).
- Diagnostic error: adb shell dumpsys fingerprint If the answer is mSensor=null or Error:-2 (hardware malfunction code).
Cost of repair in official Xiaomi services (2026):
- Optical sensor replacement (under the screen): 3,500–6,000 ₽.
- Replacement of ultrasonic sensor (side sensor): 4,000-7,500 ₽.
- Replacement of the capacitive sensor (rear): 2,000–4,500 ₽.
- Diagnosis (if the cause is unclear): 500–1,500 ₽.
Tips before visiting the service:
- 📋 Save it. IMEI phone number (dial *#06#).
- 🔄 Make a backup copy through Settings → The phone. → Backup.
- 📄 Bring checks or a warranty card if the phone is guaranteed.
- 🔧 If the phone was disassembled, honestly report it to the master - it will save time for diagnosis.