Checking the bootloader on Xiaomi via ADB: a complete guide with commands and nuances

The bootloader on Xiaomi smartphones is a critical component that controls the process of launching the operating system. Its status (unlocked or locked) affects the ability to install custom firmware, obtain root rights, or even restore the device after a crash. However, standard MIUI settings do not provide direct information about the status of the bootloader, which forces users to turn to tools like ADB (Android Debug Bridge).

This article will help you understand how to check the bootloader on Xiaomi through ADB without the risk of damaging the device. We will look not only at the basic commands, but also at the typical errors, ways to fix them, as well as the nuances of working with different models - from Redmi Note 10 Pro to flagship Xiaomi 14 Ultra. Special attention is paid to security: you will learn what actions can lead to blocking the Mi Account or the "brick" of the device, and how to avoid them.

What is a Xiaomi bootloader and why check it

A bootloader is a low-level software that runs to the operating system. On Xiaomi devices, it is locked by default, which protects the system from unauthorized changes, but limits the possibility of customization. ADB relevant in several cases:

🔓 Before unlocking for installation TWRP or custom firmware (for example, LineageOS).
🛠️ After a failed update, if the device is stuck on the logo MI.
🔍 When buying a used smartphone to make sure the previous owner has not made changes to the system partitions.
📱 To diagnose performance problems if you suspect a modified bootloader is the fault.

It is important to understand that an unlocked bootloader deprives the device of an official warranty Xiaomi and can cause a denial of service.In addition, some banking applications (for example, SberBank Online or Tinkoff) can block work on such devices due to security risks.

⚠️ Note: If you plan to unlock the bootloader, note that Xiaomi links this action to the Mi Account. When you reset the device without detachment of the account, it may be blocked (Mi Account Lock).

Preparation for the test: what will be needed

To check the status of the bootloader through ADB, prepare the following:

📱 Xiaomi smartphone with enabled debugging USB (guideline).
🖥️ Computer running Windows, macOS or Linux.
🔌 USB-Type C cable (preferably original to avoid connection issues).
🛠️ Installed drivers ADB and Fastboot (links to official sources are given below).
📦 Google’s Platform Tools Package (includes adb.exe and fastboot.exe).

If you are using Windows, download drivers from the official Android website. For macOS/Linux, it is enough to install Platform Tools through a package manager or manually:

# For macOS (via Homebrew)


brew install android-platform-tools




For Linux (Debian/Ubuntu)



sudo apt install android-tools-adb android-tools-fastboot

On your smartphone, activate the developer mode and debugging via USB:

Go to Settings. → The phone.
Tap 7 times on the MIUI version until the notification “You became a developer” appears.
Back to Settings → Additionally. → For developers.
Turn on USB debugging and confirm the action.

☑️ Preparation for loader inspection

Install Platform ToolsDownload the ADB driversEnable the developer modeActivate debugging over USBConnect your smartphone with the original cable

Done: 0 / 5

Step-by-step: how to check the bootloader through ADB

When you are ready, follow this instruction:

Connect your smartphone to your PC and select File Transfer (not Charge!) mode.
Open the command line (Windows) or terminal (macOS/Linux) in the folder with the platform-tools.
Check the connection command: adb devices If the device appears in the list – the connection is successful.
Go to Fastboot: adb reboot bootloader Smartphone reboots into a black screen with the inscription FASTBOOT and the logo Mi Bunny.
Check the status of the bootloader command: fastboot oem device-info In the conclusion, find the line Device unlocked: true - the bootloader is unlocked. false - the bootloader is locked.

On some models (e.g., POCO F5 or Redmi K60), the fastboot oem device-info command may not work.

fastboot getvar unlocked

If the answer is unlocked: yes, the bootloader is unlocked.

What to do if the team is not working?

On some devices (especially new ones), Xiaomi blocks access to bootloader information through standard commands. In this case, try: 1. Use fastboot flashing unlock - if the bootloader is blocked, the command will return the error. 2. Reflash the device through the Mi Flash Tool with the clean all option (this will reset all data!). 3. Contact the service center if the device is guaranteed.

Common mistakes and their solutions

When checking a bootloader through ADB, users often encounter errors, and here are the most common ones and ways to fix them:

Mistake.	Reason.	Decision
no permissions (user in plugdev group; are your udev rules wrong?)	There are no rights to access Linux USB-device.	Add a rule for udev or run a command with sudo.
Device not found or an empty list in adb devices	Drivers are not installed, the cable is faulty or the debugging mode is not activated.	Check the connection, reinstall the drivers, try another cable.
FAILED (remote: 'Flashing is not allowed in Lock State')	Attempt to execute a command requiring an unlocked bootloader.	Unlock the bootloader through the Mi Unlock Tool (requires binding to the Mi Account).
Waiting for device (waiting)	The smartphone has not switched to Fastboot mode or drivers are not working correctly.	Forced reboot the device in Fastboot buttons Power + Volume down.

⚠️ Note: If you see a Device critical unlocked: true string after the fastboot oem device-info command, it means that the bootloader was unlocked in an informal way (for example, through exploits). MIUI and the operation of Google services.

📊 What method of unlocking the bootloader you used?

Official (Mi Unlock Tool)

Informal (exploitations)

I didn't unlock it.

I don't know.

Features of checking on different models Xiaomi

The procedure for checking the bootloader through ADB is universal, but some Xiaomi models have nuances:

📱 Redmi Note 8/9/10 Fastboot oem device-info commands work stably, but on firmware older MIUI 12.5 You may need to log in to your Mi Account even to read the information.
📱 POCO F1/F2/F3: These devices often come with an already unlocked bootloader (check through fastboot getvar unlocked).
📱 Xiaomi 12/13/14 On the new flagships, Xiaomi blocks access to some fastboot commands without linking to the account.

For devices running MediaTek processors (such as the Redmi 10C or POCO M4 Pro), the bootloader is complicated by the fact that the Fastboot may not work stable.

Use adb reboot bootloader to navigate to Fastboot.
If the device is not identified, try connecting it to another. USB-port (preferably) USB 2.0).
MediaTek may require a dedicated LibUSB or VCOM driver.

1. Press Win + X → Startup options → Reboot.

2. Select Disable the mandatory driver signature verification (7 keys).

3. After restart, reconnect.-->

What to do if the loader is blocked, and you need to unlock

If the ADB test shows that the bootloader is locked (Device unlocked: false) and you need to unlock it (for example, to install TWRP), follow the official procedure from Xiaomi:

Link your Mi Account to your device: Go to Settings → Xiaomi Account. Log in and activate Find the Device.

Mi Unlock Tool

official website

Connect the device in Fastboot mode

Follow the instructions of the program

72-168 hours

Xiaomi

Important: Once unlocked, all data on the device will be deleted.

🔒 On some models (e.g. Xiaomi) 13T) Unlocking may not be possible due to hardware limitations.
📵 After unlocking, Google Pay, Netflix may stop working HD Other services that require SafetyNet.
🔄 Xiaomi can block an account if it is unlocked too often (for example, on multiple devices in a short period of time).

⚠️ Note: Unofficial Unlocking Methods (e.g., through exploits in the MIUI 12) may result in permanent locking IMEI Use them only if you understand the risks!

💡

Officially unlocking through the Mi Unlock Tool is the only safe way, but requires waiting and resetting data.Unofficial methods are risky and can lead to a device "brick."

Safety and Risks: What Not to Do When Working with a Booter

Working with the bootloader through ADB/Fastboot is an interference with the system components of the device, errors here can lead to serious consequences, up to the complete loss of the smartphone's performance.

🚫 Interrupting the process while executing fastboot commands (e.g., turning off the cable or pulling out the battery) can cause damage to the boot partition.
🚫 Use commands like fastboot erase or fastboot flash without understanding how they work. A syntax error can erase critical partitions.
🚫 Trying to unlock the bootloader on enterprise firmware devices (e.g. Xiaomi for business) often results in hardware locking.
🚫 Install TWRP Or custom firmware on devices with a locked bootloader through a fastboot boot. This only works temporarily and can cause looping of the boot.

If you do encounter a problem (e.g., the device is not turning on or stuck on the MI logo), try the following steps:

Flash the device through the Mi Flash Tool with the clean all option (delete all data!).
If Fastboot is not defined, try EDL mode (requires an authorized Mi Account or Qualcomm box).
Contact the Xiaomi Service Center if you are not sure about your actions.

Remember: unlocking the bootloader will void the warranty, and incorrect actions can make the device unsuitable for recovery even in the service center.

FAQ: Frequent questions about checking the bootloader on Xiaomi

Can I check the status of the bootloader without ADB?

No, standard MIUI settings don’t display bootloader status, and the only alternatives are special applications like Bootloader Status (require root) or Fastboot visual verification (locked devices display LOCKED under the Mi Bunny logo).

Why does the fastboot oem device-info command return an empty output?

This is typical of new Xiaomi models (e.g. Redmi Note). 12 Xiaomi 13), where the manufacturer has restricted access to the bootloader information. Try alternative commands: fastboot getvar unlocked fastboot flashing get_unlock_ability If they don’t work, you may need to unlock the device via the Mi Unlock Tool.

What is the status of critically unlocked: true?

This indicates that the bootloader was unlocked in an informal way (e.g., through exploits in older versions of MIUI). Such devices may have problems: Denial of MIUI Updates by Air (OTA) blocking Google services (e.g., Google Pay or Widevine L1 for Netflix in HD).

Can I unlock a bootloader on Xiaomi without waiting 7 days?

Officially, no. Xiaomi has introduced a mandatory wait to protect users from random action. However, there are informal methods (e.g., through EDL or exploits), but they: Require deep technical knowledge. Can lead to IMEI blocking or hardware damage. Do not work on new models (e.g., Xiaomi 14 or Redmi Note 13). The risks usually outweigh the benefits of accelerated unlock.

How to check the bootloader on Xiaomi with a MediaTek processor?

Devices on MediaTek (e.g. Redmi 10A or POCO M5) often have problems with Fastboot.To check the bootloader: Make sure MediaTek Preloader drivers (e.g. LibUSB) are installed. Use fastboot getvar unlocked instead of fastboot oem device-info. If the device is not identified, try to transfer it to Fastboot with Power + Volume down buttons (hold 10-15 seconds). On some MediaTek models, the bootloader status can only be checked via SP Flash Tool in Download Agent mode.