Fingerprint on Xiaomi Redmi Note 4: how to set up and use

Xiaomi Redmi Note 4 (codenamed mido) is still one of the brand’s most popular budget smartphones, despite the release of new models. One of the key advantages of the device is the built-in fingerprint scanner, which significantly speeds up unlocking and improves security. However, many users face problems when setting it up: the sensor does not respond, the system emits errors, or the feature is simply absent from the menu.

In this article, we will discuss all the ways to activate a fingerprint on the Redmi Note 4, including official and alternative methods. You will learn how to add a fingerprint through standard settings, what to do if the scanner does not work after firmware, and how to avoid common errors such as "Fingerprint Sensor is not responding." Can the scanner be hacked, how to protect the data if the phone is stolen, and whether to use a fingerprint instead of a fingerprint? PIN-code.

If you’ve just bought a used Redmi Note 4 or upgraded your firmware, this will help bring back the sensor’s functionality, and for power users, we’ve prepared a section with advanced settings through ADB and TWRP.

Preparing the smartphone before setting up the fingerprint

Before adding a fingerprint, there are several steps that must be taken, without which the system can block access to the sensor or issue an error.

First, make sure your Redmi Note 4 has official MIUI firmware (versions 8-12) or custom scanner-enabled firmware (like LineageOS or Pixel Experience). On some unofficial builds, the sensor may not work due to lack of drivers. You can check the MIUI version in Settings → About Phone → MIUI version.

First, you need to install a pattern lock or PIN-This is a security requirement: Android doesn't allow biometrics to be used without backing up the unlock method. If you already have a password set, skip this step. If not, go to Settings. → Lock screen → Set a password and select PIN or a pattern lock.

Install PIN-code|Update MIUI last-minute|Clean the sensor of dirt and moisture|Make sure there is no damage to the finger (cuts, calluses)-->

You should also clean the fingerprint sensor, which is located on the back of the camera, use dry soft tissue (such as a microfiber) and avoid alcohol-containing liquids that can damage the coating, and if the sensor is contaminated, the scanner will fail to recognize the fingerprint.

Fingerprint.|PIN-code|pattern lock|Face (Face Unlock)|Other-->

Official method: Adding a fingerprint through settings

The easiest and safest method is to use the standard MIUI menu, which is suitable for most users and does not require technical skills.

Step instructions:

1. Open the settings (cog icon on the desktop).
2. Go to Lock Screen and Password (or Security in older versions of MIUI).
3. Select Fingerprint Addition. The system will request the current PIN-code-key.
4. Follow the hints on the screen: put your finger on the sensor and raise it when the vibration appears. Repeat the process 6-8 times until the scanner captures the fingerprint completely.
5. Name the print (for example, "Indicative right") and save.

Once you add a print, it can be used to:

• 🔓 Unlock the screen (press the power button and attach your finger).
• 🛡️ Confirmation of payments in Mi Pay or banking applications.
• 🔒 Hiding notifications on a locked screen (in privacy settings).

💡

If the scanner doesn't recognize the fingerprint the first time, try registering the same finger again under a different name, which sometimes solves the sensor sensitivity problem.

Important: Redmi Note 4 can save up to 5 fingerprints. If you're trying to add a sixth, the system will suggest removing one of the existing ones. It's a hardware limitation, you can't get around it without modifying the firmware.

Typical errors and their solutions

Even when set up correctly, Redmi Note 4 users often encounter scanner problems, and let’s look at the most common bugs and how to fix them.

If none of these things worked, the problem could be hardware damage, and the fingerprint sensor on the Redmi Note 4 is connected to the motherboard through a flexible plume that wears out over time, which would require a replacement of the sensor or plume at the service center.

Advanced settings via ADB and TWRP

For power users who have a fingerprint scanner that doesn’t work due to software limitations, there are ways to activate via ADB (Android Debug Bridge) or TWRP. These methods require an unlocked bootloader and can result in a data reset, so use them at your own risk.

Method 1: Enabling biometrics service through ADB

If the fingerprint function is hidden in the menu, it can be forced to activate by commands:

adb shell


su




setprop persist.sys.fp.enable 1




reboot

After rebooting, check for the fingerprint option in the settings. If it is not available, try resetting BiometricService:

adb shell pm clear com.android.biometrics

Method 2: Installation of Magisk module for scanner

On custom firmware (e.g. LineageOS), the sensor may not work due to the lack of drivers.

1. Install Magisk Manager and unlock root.
2. Download Fingerprint Enabler for Mido (available on XDA Developers)
3. Install the module via Magisk and restart the phone.

💡

Using ADB and Magisk can disrupt system integrity and lock the bootloader.Before experimenting, back up via TWRP!

Security: Can I cheat the fingerprint scanner?

Many users worry about the reliability of biometric security, so let's look at how secure the fingerprint scanner on the Redmi Note 4 is and how to protect data in the event of a phone theft.

Scanner vulnerabilities:

• 🔍 Fraud: It is theoretically possible to create a cast of a finger from a high-quality photograph, but in practice it requires specialized equipment (cost) ~$2000+).
• 💻 Data Leak: Fingerprints are stored in a Trusted Execution Environment, but vulnerabilities are not available. MIUI (For example, versions up to 10.2) allowed them to be extracted through exploits.
• 🔄 Reset to factory settings: After reset, all fingerprints are deleted, but an attacker can access the phone via Fastboot if protection is not turned on OEM Unlock.

How to strengthen protection:

1. Use the print together with PIN-code (set the request) PIN post-boot).
2. Disable Smart Lock (automatic unlocking in trusted locations).
3. Install the AppLock application to block critical programs (banks, instant messengers).
4. Update MIUI regularly – new versions fix biometric vulnerabilities.

💡

If you sell or transfer Redmi Note 4 to another person, be sure to delete all fingerprints in the Settings → Fingerprints menu. Even after reset, some custom firmware retains biometrics!

Alternatives to fingerprint: Face Unlock and other methods

If the fingerprint scanner on your Redmi Note 4 is out of order or is not working properly, consider alternative unlocking options that are less reliable but can temporarily replace biometrics.

1. Face Unlock (Face Unlock)

Available in MIUI 9+ via Settings → Lock screen → Face unlock. It works on the front camera, but it's not safe - you can fool the system with a photo. It's only for convenience, not for data protection.

2. Voice unlocking

The Voice Password feature in Google Assistant allows you to unlock your phone with a phrase (e.g., “OK, Google, unlock”). Settings: Google Settings → Voice Search → Voice Unlock.

3. Smart key fobs (Trust Agents)

Android supports unlocking via Bluetooth devices (such as smartwatches or headphones). Activates in Settings → Security → Reliable devices. Minus: if the key fob is lost, the phone will remain unprotected.

Frequent questions about the fingerprint scanner on Redmi Note 4