How to unlock Mi Band 4: full instructions for all cases

Xiaomi Mi Band 4 fitness bracelet can be blocked for several reasons: after repeated incorrect input PIN-Unlike newer models (such as the Mi Band 7), the fourth version does not have a hardware reset button, making it difficult to unlock for inexperienced users.

In this article, we will look at all the current ways of unlocking, from a standard reset via the application to manual intervention through ADB (for advanced users), paying special attention to the typical errors that lead to a complete loss of functionality of the bracelet, such as interrupting the process of updating the firmware or improperly linking the Xiaomi account. If your Mi Band 4 shows the inscription “Locked” or stopped responding to touches, the following instructions will help bring it back to life without contacting the service center.

1 Unlocking through the Mi Fit app (official method)

The safest and most recommended method is to use the official Mi Fit app (or its Zepp Life equivalent for newer versions), which is suitable if the bracelet is blocked due to incorrect use. PIN-code-break.

Important: Before you start, make sure that:

• 📱 The latest version of Mi Fit is installed on the smartphone (you can download it from Google Play or the App Store).
• 🔋 The bracelet's charge level is at least 20.
• 🔗 Mi Band 4 bracelet tied to your Xiaomi account (if not, you will need a reset).

Step-by-step:

1. Open the Mi Fit app and go to Profile → Mi Smart Band 4.
2. Slap three points (⋮) in the upper right corner and select Unlock the device.
3. Enter. PIN-code from the bracelet (if you have changed it) or use the standard code 0000, 1234.
4. Confirm the action via SMS or fingerprint (if two-factor authentication is enabled).

⚠️ Warning: If the bracelet doesn’t respond to touch, but connects to your phone via Bluetooth, try rebooting it. To do this, connect the Mi Band 4 to charging and hold the touch button for 10-15 seconds until the Xiaomi logo appears.

2. reset to factory settings (Hard Reset)

If the official method didn’t work or the bracelet didn’t sync with the app, it would require a complete reset, which would remove all the data from the device (steps, pulse, settings), but would restore control.

For the Mi Band 4, there are two options for resetting:

• 🔄 Software reset – via the bracelet menu (if the screen responds to touches).
• 🔌 Hardware reset - through the charger (if the bracelet does not respond).

Method 1: Program reset

1. On the bracelet, swipe down the screen to open the menu.
2. Select Settings → Reset (circular arrow icon).
3. Confirm the action by tapping the tick, the bracelet will reset and return to factory settings.

Method 2: Hardware reset (if the screen is not working):

1. Connect the bracelet to the charger.
2. Hold the touch button for 15-20 seconds until the Xiaomi logo and vibrations appear.
3. Release the button - the bracelet will reset and reset.

After resetting the bracelet will be like a new one – it will need to be re-associated with the Xiaomi account via Mi Fit. If the binding does not pass, check:

• 📶 Internet connection stability (bracelet downloads updates on the first connection).
• 🔒 No regional restrictions (some firmware blocks binding in certain countries).

3. Unlock through ADB (for advanced users)

If the bracelet is locked after a failed firmware update or shows a "Device Locked" error, unlocking via ADB (Android Debug Bridge) can help.This technique requires technical skills and is only suitable for users familiar with the command prompt.

Importantly, the wrong ADB commands can permanently disable the bracelet, and only use this method if other options fail.

Step-by-step:

1. Download and install Platform Tools (includes ADB and Fastboot).
2. Connect the bracelet to your PC via Bluetooth (use an adapter with BLE 4.2+ support).
3. Open the command prompt (cmd in Windows or Terminal in macOS/Linux) and type:

adb devices

If the bracelet appears in the list, do:

adb shell


su




am broadcast -a com.xiaomi.hm.health.FT_RESET

Once the commands are done, the bracelet will reset and reset the lock. If the command does not work, try the alternative:

adb shell am start -n com.xiaomi.hm.health/com.xiaomi.hm.health.ft.FTResetActivity

⚠️ Note: Some Mi Band 4 firmwares have access to ADB In this case, you will need to first flash custom firmware (for example, Notify & Fitness), which carries the risk of “bricking” the device.

4 Unblocking after changing Xiaomi account

One of the common problems is that the bracelet is tied to an old Xiaomi account, and you don’t remember the login details, in which case a standard reset won’t help: after a reboot, the Mi Band 4 will require authorization to the previous account.

Decisions:

• 🔑 Restore access to your old account through the recovery page (you will need an email or phone linked to your account).
• 📧 Contact Xiaomi with proof of purchase (check, box) – they can remove the binding remotely.
• 🔧 Sweep through custom firmware (such as Mi Band 4 Custom Firmware) that removes the link to your account. 4PDA.

If the bracelet is purchased from hand and the previous owner has not untied it, contact him - without this, unlocking by official means is impossible. The alternative is firmware via nRF Connect, but this voids the warranty and can lead to loss of functions (for example, measuring the pulse).

5 Unlocking after firmware update

Sometimes Mi Band 4 is blocked after an automatic firmware update.

• 🔄 Interrupted update process (for example, battery is down).
• 📱 Incompatibility of the firmware version with the region (Chinese bracelets can be blocked in Europe).
• 🔒 Conflict with custom firmware.

To unlock the bracelet:

1. Connect it to charging and wait for full charging (at least 50%).
2. Hold the touch button for 10 seconds for a forced reboot.
3. If the screen flashes and shows an error, reset via Mi Fit (Settings → Untie the device).
4. Reconnect the bracelet to the account - the application will offer to download the current firmware.

💡

If the bracelet starts to discharge quickly after the upgrade, reset it to the factory settings and re-attach it, often solving autonomy problems.

Hardware malfunctions: when unlocking is not possible

If none of these methods worked, the problem could be a hardware breakdown.

• 🔋 The bracelet does not charge (even after cleaning the contacts).
• 📱 Not detected by phone over Bluetooth (not displayed in the list of devices).
• 💥 It is constantly overheating or gives off an unpleasant smell.

In these cases, unblocking software is useless.

• 🔋 Bloated battery – requires replacement (cost of repair) ~1000–1500 ₽).
• 🔌 Damaged power controller – often after falls or moisture.
• 📡 Faulty Bluetooth module – bracelet can’t connect to phone.

For diagnosis:

1. Try connecting the bracelet to another phone (preferably on Android 8+).
2. Check the charger and cable (use the original Xiaomi adapter).
3. Check the case for cracks or traces of oxidation (especially after contact with water).

⚠️ Warning: If the bracelet falls into water, do not plug it into charging, it may cause a short circuit. Dry the device in rice or silica gel for 24-48 hours before trying to turn it on.

💡

Most Mi Band 4 hardware breakdowns are not self-repairable. If warranty is valid, contact Xiaomi Service Center - repairs will cost less than buying a new bracelet.

7. Alternative methods: firmware and custom solutions

If the standard methods don't work, you have to run the bracelet through third-party tools, which is risky, but sometimes the only way.

• 🛠️ Notify & Fitness for Mi Band 4 - custom firmware with advanced features (notifications, widgets).
• 🔧 Mi Band 4 Custom Firmware – Removes regional restrictions and account binding.
• 📱 nRF Connect – a utility for manual control of the bracelet via Bluetooth.

Step-by-step instructions for firmware via nRF Connect:

1. Download nRF Connect on Android.
2. Connect to the bracelet via BLE (it should be displayed as MI Band 4).
3. In the section DFU Select the firmware file (for example, mi_band_4_custom.fw).
4. Start the firmware process and wait until it is completed (the bracelet will reboot).

Warnings:

• ⚠️ The firmware cancels the warranty.
• ⚠️ The wrong firmware file can "brick" the bracelet.
• ⚠️ After the firmware some functions (for example, NFC) They may stop working.

References to current firmware and instructions:

• 4PDA – Theme for Mi Band 4
• Gadgetbridge (alternative to Mi Fit)

FAQ: Frequent questions about unlocking Mi Band 4