How to Unlock the Bootloader of your BraX3

Unlocking your BraX3 bootloader gives you full access to the system and allows advanced operations like flashing custom ROMs, rooting, or performing deep-level maintenance. This guide will walk you through the official unlock method for BraX3.

:warning: Unlocking the bootloader disables certain security features. While it gives advanced users full control of the device, it also increases the risk of security and data compromise. We recommend relocking the bootloader once you’ve completed the task that required unlocking it.

:warning: Please note that locking or relocking your bootloader will erase all stored data on the device

Prerequisites

  • Android Platform Tools downloaded and extracted to your Desktop folder.
  • You have installed the latest MediaTek USB driver (Windows driver or Linux driver, depending on your Operating System)

So let’s dive into the steps.

1. Enable OEM Unlocking & USB debugging

  • Open Settings on your BraX3.
  • Tap About phone.
  • Tap Build number seven times. You’ll be prompted to enter your screen lock PIN, password, or pattern.
  • After unlocking, a message will appear: “You are now a developer!”
  • Go back to Settings > System > Developer options.
  • Scroll down and enable OEM unlocking.
  • Also enable USB debugging.

2. Unlocking the bootloader

  1. Connect your BraX3 to your PC by using a reliable USB data cable.
  2. Pres Allow when you’re prompted to Allow USB debugging.
  3. Open the Command Prompt (press Win + R, type cmd, and hit Enter) for Windows or Open your Terminal for Linux.
  4. Navigate to the Platform Tools folder using the following commands:
For Windows:
cd C:\Users\[Your Username]\Desktop\platform-tools-latest-windows\platform-tools

:light_bulb:Tip: You can get the path to your folder by clicking on the navigation bar in your file explorer. image

For Linux:
cd ~\Desktop\platform-tools_r34.0.4-windows\platform-tools
  1. Type adb devices and press enter.

:light_bulb:If successful, you should see an identifier of your connected device, with the word “device” os its right.
image

  1. Type adb reboot bootloader and press enter. The phone will now reboot into fastboot mode (when you’re in fastboot, you will see the “Brax” logo and a text “FASTBOOT MODE” at the bottom left of your screen.
  2. Type fastboot flashing unlock in your terminal and press enter. Within 3 seconds, press the Volume Up button on your BraX3 to confirm the unlock.
  3. Type fastboot flashing unlock_critical in your terminal and press enter. Within 3 seconds, press the Volume Up button on your BraX3 to confirm the unlock.

:white_check_mark: Congratulations – Your Bootloader is Now Unlocked!
You can now flash custom ROMs, root your device, or perform other advanced operations. If you only needed to unlock temporarily, we recommend relocking the bootloader after you’re done.

Want to Relock the Bootloader?

To relock your bootloader, simply follow the same steps used for unlocking, but replace the command on step 7 with fastboot flashing lock_critical and Step 8 with fastboot flashing lock.

As with unlocking, you’ll need to press the Volume Up button within 3 seconds on your BraX3 to confirm each action.

Common Issues When Unlocking the Bootloader (and How to Fix Them)

Even though the unlock process may seem straightforward, a few things can still go wrong. Here are the most common problems users run into — and how to fix them:

1. Device Not Recognized by ADB or Fastboot

Problem:
The adb devices or fastboot devices command doesn’t detect your BraX3.

Fix:

  • Ensure USB debugging is enabled in Developer Options (see step 1).
  • Make sure you’re using a high-quality USB data cable — not just a charging cable.
  • Try switching USB ports, especially using USB 2.0 instead of 3.0.
  • Reinstall or update your Mediatek USB drivers on your PC.

2. “Waiting for device” in Fastboot Mode

Problem:
Fastboot commands hang and display “waiting for device”.

Fix:

  • Use official MediaTek USB drivers (or reinstall them).
  • Make sure your device is properly in Fastboot mode (black screen with FASTBOOT MODE text in lower left corner).
  • Some systems require admin privileges — try running the Command Prompt as Administrator.

3. Didn’t Press Volume Up in Time

Problem:
You missed the 3-second confirmation window after running the fastboot flashing unlock or unlock_critical command.

Fix:

  • Re-run the command and be ready to press the Volume Up button quickly.
  • If the device reboots before you can respond, repeat the fastboot command.

4. Bootloader Unlock Options Not Available

Problem:
The device doesn’t show the option to unlock even after sending the command.

Fix: Double-check that OEM unlocking is enabled in Developer Options.

5. Command Not Recognized

Problem:
You see an error like `‘adb’ is not recognized as an internal or external command.

Fix: Ensure you’re in the correct directory — where the platform-tools folder is located.

6. Stuck in Bootloop After Unlock

Problem:
After unlocking, the device doesn’t boot properly or loops at the startup screen.

Fix:

  • This is rare, but if it happens, try entering recovery mode and doing a factory reset.
  • If that doesn’t work, you may need to flash stock firmware using SP Flash Tool or a similar utility.
4 Likes

little error

and reboot bootloader
needs to be
adb reboot bootloader

we could even say that for windows user , when you are in paltform-tools folder
./adb.exe reboot bootloader

for the testing unit, we see the Android logo in fastboot mode.

4 Likes

@plamen please note the previous post by @LostEther and edit your first post accordingly

1 Like