The fingerprint scanner on the Redmi Note 8 Pro does not work: all the reasons and how to fix it

The fingerprint sensor on the Xiaomi Redmi Note 8 Pro is a key element of security and convenience, but many users face unstable work. Problems are manifested in different ways, from a complete lack of response to touch to accidental positives or a “fingerprint sensor does not respond.” In most cases, not only hardware breakdowns, but also software failures that can be fixed independently.

In this article, we will look at all the possible causes of a scanner malfunction, from simple contamination to damage to the plume, and give step-by-step instructions for diagnosis and repair. Special attention will be paid to the unique features of the Redmi Note 8 Pro, including problems with firmware and accessory compatibility. If you have tried to reset or clean the sensor, but nothing has worked, here you will find solutions that are not written about in the standard guides.

Before you start repairing, it’s important to understand that the fingerprint sensor on this model is integrated into the power button, rather than being located under the screen, as in the new flagships. It’s both a plus (less risk of damage when replacing the screen) and a minus (more mechanical wear). Redmi Note 8 Pro is also known for problems with the MIUI 12+, where the scanner may conflict with the face unlock function, and then we'll go through each cause in detail.

1. Pollution of the sensor or power button

The most obvious, but often ignored, cause is the accumulation of dirt, fat, or moisture on the scanner's surface, because the sensor is coupled with the on button, it is in constant contact with fingers, too fat marks, and dust, and over time, this causes the sensor to stop recognizing the fingerprint or to fire at a time.

This is especially true for users who:

• 🧴 Often used hand creams or antiseptics (residues clog the microscopic pores of the sensor).
• 🏗️ Work in dusty or humid conditions (construction, kitchen, gym).
• 📱 Wear your phone in your pocket with coins or keys (metal dust settles on the button).

How to clean the sensor correctly:

1. Turn off the phone and remove it. SIM-card (just in case).
2. Wet the cotton swab in isopropyl alcohol (70%+) or a special liquid to clean the electronics.
3. Gently wipe the sensor surface without pressing (do not scratch!).
4. Let it dry for 5-10 minutes, then check the work.

⚠️ Warning: Do not use acetone, vodka or wet wipes - they leave a film that impairs sensitivity. Also avoid abrasive materials (for example, microfibers from glasses with coarse pile).

If after cleaning the scanner worked, but after a while the problem returned - the reason may be the wear of the protective coating of the sensor, in this case, only the replacement of the power button (more about this below).

2. Software failures and MIUI errors

MIUI (especially versions 12-14) is famous for biometric authorization bugs, and the Redmi Note 8 Pro features the following:

• 🔄 The scanner suddenly stops working after the update.
• 🚫 Error: "Fingerprint sensor does not respond" when adding a new fingerprint.
• 🔒 The phone will be unlocked only after 2-3 attempts (even with a registered fingerprint).

The first thing to do is restart your phone in safe mode:

1. Press the power button before the turn off menu appears.


2.Push and hold "Switch off" → will be prompted to go to safe mode.




3. Confirm and wait for the download.

If the scanner is working normally in safe mode, the third-party application (most often launchers, antiviruses or “optimizers”) is to blame.

If the problem persists, try resetting the scanner settings:

1. Go to Settings → Passwords and Security → Fingerprints.
2. Delete all the fingerprints you saved.
3. Reboot the phone.
4. Add the print again by following the instructions on the screen.

⚠️ Note: There is a bug on the Redmi Note 8 Pro: if you interrupt the process when you add a fingerprint (for example, remove your finger prematurely), the sensor can lock up until the next reboot!

3. Conflict with cover or film

Many users are unaware that accessories can block the sensor. On the Redmi Note 8 Pro, the power button (with a built-in scanner) is located on the side, and even minimal pressure on it can cause malfunctions.

Problem accessories:

• 📱 Hard cases with high sides (press on the button, shifting the sensor).
• 🧲 Magnetic cases (can interfere with the sensor).
• 🛡️ Armoured films with a cutout for the sensor (if the cutout is made curved, it covers part of the scanner).

How to check:

1. Take off the cover and film (if any).
2. Try unlocking your phone with a bare case.
3. If the sensor is running, the accessory is a problem. Try another case or cut the film more accurately.

Critical: AliExpress sells "universal" cases for the Redmi Note 8/8 Pro, which are not physically suitable for the Pro version due to a misaligned sensor hole. Always check compatibility!

4. Damage to the plume or sensor contacts

If the scanner stopped working after a phone fell, hit or disassembled, the power button plume is likely damaged or the contacts have gone away. On the Redmi Note 8 Pro, this plume is thin and fragile, especially at the mounting point to the motherboard.

Signs of hardware breakdown:

• 🔌 The sensor does not respond at all (no vibration when touched).
• 🔄 The power button works, but the scanner doesn’t (or vice versa).
• 💥 The phone stopped turning on after disassembly (possibly the plume broke off completely).

What you can do on your own:

1. If you have a warranty phone, don't take it out!
2. If the warranty is over: Disassemble the phone (you need a plastic spatula and a screwdriver). T3). Check if the plume has moved away from the motherboard (it is attached with a small connector). If the plume is torn, you will need to change the power button (cost). ~1500–2500 ₽).

⚠️ Attention: If you've never taken your phones apart, don't take risks! On the Redmi Note 8 Pro, the power button plume is soldered to the board, and if you're not sloppy, you can tear off the contact areas.

5. Problems after firmware update

The Redmi Note 8 Pro is particularly sensitive to MIUI and Android updates, and many users complain that when a new firmware is installed, the scanner stops working or starts to glitches, most often when switching to:

• 📱 MIUI 12.5 → MIUI 13/14 (Changes in biometric drivers).
• 🤖 Android 10 → Android 11 (Security Stack Update).

How to fix it:

1. Reverse to the previous version of MIUI (if the scanner worked before the update). To do this: Download the old firmware from the official Xiaomi website. Go to Settings → About Phone → System Update → Three points → Select a firmware file. Select the downloaded file and wait for the rollback.

reset to factory settings

Custom Recovery (TWRP)

If the scanner doesn’t work even after a rollback, the problem may be in damaged memory areas (for example, persist, where biometric data is stored), in which case only a complete flashing through the Fastboot will help.

Make a data backup|Charge your phone at least 50 times%|Download the correct version MIUI for your model|Disable the Mi Account lock (if any)|Prepare cable and PC-->

6. Wear or factory defect of the sensor

The fingerprint scanner on the Redmi Note 8 Pro is a Goodix optical sensor that wears out over time. The average lifespan is 3-5 years when you're in active use. If your phone is older, the problem may be:

• 🔍 Loss of sensitivity (sensor "clogged" and ceases to recognize fingerprints).
• 💡 Burn-out backlights (the scanner cannot read the finger pattern).
• 🏭 Factory marriage (rarely, but occurs in parties of 2019-2020).

How to check the wear:

1. Try registering a new fingerprint (if the sensor does not respond to the addition, it is defective).
2. Light a flashlight on the sensor: if you see cracks or darkening, you need a replacement.
3. Connect your phone to your PC and check logs via ADB: adb shell dumpsys fingerprint If there are errors in the logs such as Error: -22 (hardware malfunction), the sensor must be changed.

Replacing the sensor on the Redmi Note 8 Pro will cost 1800-3500 ₽ (Important: only use the original power button with the sensor - Chinese counterparts are often incompatible with the original part. MIUI.

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Before replacing the sensor, check if your phone has an extended warranty (sometimes Xiaomi covers the repair of biometric sensors even 2-3 years after purchase).

7 Conflict with other unlocking functions

On the Redmi Note 8 Pro, the fingerprint scanner can conflict with:

• 👤 Facial recognition (if both functions are enabled, the system may be confused").
• 🔐 Smart Lock (automatic unlocking in trusted locations).
• 📱 Third-party launchers (e.g., Nova Launcher or POCO Launcher).

How to resolve conflict:

1. Turn off facial recognition in Settings → Passwords and Security → Face recognition.
2. Remove all Smart Lock rules in Settings → Passwords & Security → Smart Lock.
3. Return to the standard MIUI launcher (if you used a third-party one).
4. Restart your phone and check the scanner.

The unique feature of the Redmi Note 8 Pro is that if you simultaneously turn on the fingerprint and face recognition, the system can "forget" the registered fingers after rebooting. MIUI, which has not yet been corrected.

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If the scanner is unstable, first disable all alternative unlock methods (face, Smart Lock, PIN-It often solves the problem without additional actions.

FAQ: Frequent Questions About the Redmi Note Fingerprint Scanner 8 Pro