Fastboot on Xiaomi Redmi 4X: a complete guide for beginners and experienced users

Fastboot mode on Xiaomi smartphones is a powerful tool that allows you to access low-level features of the device. If you own Xiaomi Redmi 4X (codenamed santoni), sooner or later you may have to use this mode - whether to unlock the bootloader, firmware custom recovery or restore "brick" phone. However, not all users understand what Fastboot is, how it differs from Recovery Mode, and the risks of its misuse.

In this article, we will discuss in detail what is a Fastboot on Xiaomi Redmi 4X, in what cases it may be needed, and how to avoid typical errors. You will also learn which fastboot commands are most in demand for this model, how to prepare a computer to work with the device, and what to do if the phone “hangs” in Fastboot mode.

If you've never worked with Fastboot before, don't worry: we'll explain everything in simple language, with step-by-step instructions and visual cues. For experienced users, we've prepared advanced tips for working with EDL Mode and bypassing Mi Account locks. Let's start with the basics!

What is Fastboot on Xiaomi Redmi 4X and why is it necessary?

Fastboot (or Bootloader Mode) is a special smartphone state in which the Android operating system does not boot, but basic commands are available to control the device via a computer. On Xiaomi Redmi 4X, this mode is activated by a combination of buttons or the adb reboot bootloader command.

Unlike Recovery Mode, where you interact with your phone via an on-screen menu, Fastboot requires you to connect to your PC and use the fastboot utility (part of the Android SDK).

• 🔓 Unlock the bootloader (bootloader) for installing custom firmware;
• 📥 Sending official and unofficial images ROM;
• 🔄 Restore the device after failures ("disruption");
• 🛠️ Install custom Recovery (TWRP, OrangeFox);
• 📡 Update radio modules and other low-level components.

The Redmi 4X Fastboot is especially important because it supports unlocking the bootloader through the official Mi Unlock Tool. However, without understanding how this mode works, you risk losing data or locking the device. For example, the wrong fastboot erase command can erase critical partitions, and the interrupted firmware can lead to the loss of IMEI or a broken camera.

⚠️ Attention: Xiaomi Redmi 4X base-fixed MIUI 12+ Unlocking the bootloader requires you to link your Mi Account to your device. Without that, even the official Mi Unlock Tool won't work!

How to Sign In to Fastboot on Xiaomi Redmi 4X: 3 Proven Ways

There are several ways to activate Fastboot on Redmi 4X. The choice of method depends on the state of the device: whether it works normally, hung on the logo or not at all.

Method 1: Hardware buttons (for switched off phone)

1. Turn off Redmi 4X (press the power button and select Turn off).
2. Press and hold the Volume button down (-) + Power button.
3. Hold for 5-10 seconds until a screen with the inscription FASTBOOT and the image of a hare in a hat appears.

Method 2: ADB (if the phone is on)

If the device is working but you need to reboot to Fastboot, use ADB commands:

adb devices


adb reboot bootloader

The first command checks the connection of the device, the second - reboots it in Fastboot.

Method 3: Through the Recovery Menu (if available)

If you are already in Recovery Mode, select Reboot to Bootloader (navigation with volume buttons, confirmation - power button).

After a successful login, the Redmi 4X screen will look like this:

⚠️ Note: If your phone is not computer-defined after you log in to Fastboot, check the Qualcomm and Xiaomi drivers. On Windows, they can be installed via the Mi Flash Tool or manually through Device Manager.

Fastboot for Xiaomi Redmi 4X: What can and can’t be done

The fastboot utility allows you to send commands directly to the bootloader, and below is a list of the most useful commands for the Redmi 4X, divided into categories.

However, there are commands that are not recommended to be used without extreme necessity:

• 🚫 fastboot erase userdata erases all user data (photos, contacts, applications);
• 🚫 Fastboot flash boot – Boot partition firmware can lead to bootloop;
• 🚫 fastboot oem lock – locks the boot loader (re-unblocking is required).

On the Redmi 4X, the fastboot oem edl command is especially dangerous - it transfers the device to EDL Mode (emergency mode for firmware via Mi Flash), without the correct firmware in this mode, the phone can turn into a "brick".

Unlocking the bootloader on Xiaomi Redmi 4X via Fastboot: Step-by-step instructions

Unlocking the bootloader is a must for custom firmware or recovery. On the Redmi 4X, this is done through the official Mi Unlock Tool, but with a number of nuances.

Step 1: Prepare your Mi Account

• 📱 Link your Mi Account to your phone in settings (Settings) → Mi Account).
• 🌐 Go to the site. en.miui.com/unlock Download the Mi Unlock Tool.
• 🔗 Sign in to the tool with the same account as on the phone.

Step 2: Sign in to Fastboot and connect to PC

1. Put Redmi 4X into Fastboot mode (see section above).
2. Connect your phone to your computer via the original USB Type-C cable.
3. Launch the Mi Unlock Tool on behalf of the administrator.

Step 3: Unlocking

In the program window, press Unlock. It takes 1-3 minutes. Once successfully unlocked, the phone automatically restarts and all data is erased!

Once unlocked, the bootloader status will change to unlocked.

fastboot getvar unlocked

Xiaomi Redmi 4X firmware via Fastboot: official and custom ROM

Fastboot mode allows you to flash Redmi 4X both official images through the Mi Flash Tool and custom firmware (for example, LineageOS or Pixel Experience).

Official firmware through Mi Flash Tool

1. Download the firmware for Redmi 4X (codename santoni) from MIUI Downloads (select the Fastboot version).
2. Unpack the archive in a folder without Cyrillic characters (for example, C:\MIUI\santoni).
3. Open the Mi Flash Tool, press Select and point the path to the firmware folder.
4. Connect Redmi 4X in Fastboot mode and press Refresh – the device must be determined.
5. Select the firmware method: Clean all – complete cleaning (recommended in case of failures); Clean all and lock – cleaning + lock bootloader; Save user data – data storage (not always stable).

Flash

Installation of custom firmware

For custom firmware, you will need:

1. Unlocked boot loader (see previous section).
2. Installed Custom Recavery (TWRP)
3. Downloaded firmware image (for example, from the XDA Developers forum).

Fastboot firmware in this case boils down to installing TWRP:

fastboot flash recovery twrp-3.7.0-santoni.img


fastboot boot twrp-3.7.0-santoni.img

Further installation of firmware occurs through the TWRP menu.

💡

Before you run your custom ROM firmware, check for compatibility with the Redmi 4X (codename santoni) and the firmware from Redmi 5A (riva) or other models will result in a broken device!

Typical Fastboot Errors on Xiaomi Redmi 4X and How to Fix Them

Fastboot is often a bit of a bug, especially for beginners, and let’s look at the most common problems on the Redmi 4X and how to solve them.

The FAILED (remote: 'Flashing is not allowed in Lock State') error is particularly insidious, meaning that the bootloader is locked, and even the official firmware won't install without unlocking.

1. Unlock the bootloader (see section above).
2. Repeat the firmware.

If the Fastboot Redmi 4X has stopped turning on after manipulation (black screen, vibration without image), try:

• 🔌 Press the power button for 20-30 seconds (hard reset).
• 🔄 Transfer to EDL Mode (clamping the volume up) + Loudness down + Power and flash through the Mi Flash Tool.
• 📡 Contact the service center if the problem is in the hardware (for example, the eMMC chip is damaged).

💡

If after a failed firmware, the phone does not respond to buttons, but is determined by the computer in Device Manager as Qualcomm HS-USB QDLoader 9008, This means that the device is in mode. EDL. In this case, only firmware through the Mi Flash Tool with a file selection will help. prog_emmc_firehose.mbn.

Security and backup before working with Fastboot

Any manipulation in Fastboot mode carries the risk of data loss or device failure. On Redmi 4X, the following are particularly vulnerable:

• 📸 Continue (responsible for the IMEI and serial number);
• 🔋 Modem section (contains radio modules for communication);
• 📱 Userdata (all user files).

Before working with Fastboot, it is necessary to:

1. Create a backup copy through TWRP (if installed).
2. Save the IMEI (you can use the MTK Engineering Mode app or the fastboot getvar imei command).
3. Charge the battery by at least 70% (interrupting the firmware due to discharge = "brick").
4. Download the official firmware for your model in case of recovery.

To back up IMEI on Redmi 4X (Qualcomm Snapdragon 435), you can use:

fastboot getvar imei


fastboot getvar meid

Save the output of commands to a text file. IMEI It can be reset to 0 or Null, and it can be restored through QCN-file (requires) EDL Mode and specialized software like QPST).

⚠️ Attention: On Redmi 4X firmware MIUI 11+ unlocking the bootloader resets the module driver NFC (Once unlocked, the module may stop working - this is a feature of Xiaomi firmware, which can only be fixed by flashing it.

FAQ: Frequent questions about Fastboot on Xiaomi Redmi 4X