How to reflash Xiaomi Redmi 9A: official and custom firmware

Xiaomi Redmi 9A — One of the most popular budget smartphones, but even it eventually begins to slow down or requires updating to the current version. MIUI. Flashing can solve performance problems, add new features, or even bring the phone back to life after a software failure.However, improper actions lead to a “bricking” of the device, loss of warranty or locking. IMEI.

In this guide, we will look at all the formal and informal ways to run Redmi 9A (codename dandelion), including unlocking the bootloader, choosing the right version of MIUI, and solving common errors. We will focus on data security — how to save photos, contacts, and apps before the procedure. If you have never flashed your smartphone before, start with the official method through MIUI Updater, which is the simplest and least risky.

Preparation for firmware: what to do before the start

Firmware without preparation is like roof repairs in rain. 90% of the problems are due to missed steps at this stage. Let's start with the most important thing: Redmi 9A has a bootloader that you have to unlock to install custom firmware. Official updates through MIUI Updater or Recovery don't require this, but they still require backup.

Here’s what to do before any type of firmware:

• 📱 Check the phone model: go to Settings → The phone. → Model, should be Redmi. 9A (dandelion code) firmware from another model (e.g, 9C) will cause the device to fail.
• 🔋 Charge the battery to at least 60%. When discharged during firmware, the phone can turn into a "brick" (will not respond to buttons and charging).
• 💾 Make a backup: Use Settings → Additionally. → Backup and reset → Local backup or third-party utilities like Swift Backup (requires root). MI Cloud will not save applications and their data!
• 🔗 Download drivers: to work with Fastboot or ADB You need Xiaomi drivers on your PC. Install them from the official website or through Mi. PC Suite.

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If you are flashing your phone for sale, reset to factory settings (Settings) → Additionally. → Reset settings) Before you install a new firmware, this will remove the link to your account. MI and avoid blocking for the new owner.

Pay special attention to the choice of firmware version. Redmi 9A is relevant:

• 🌍 Global (Global): MIUI Global Stable is the official firmware for the international market, supports Google Services, but updates less often than the Chinese one.
• 🇨🇳 Chinese (China): MIUI China Stable – Gets Updates Faster, But Without Google Services (You Have to Manually Install).
• 🛠️ Custom (Custom) ROM): For example, LineageOS or Pixel Experience, require unlocked bootloader and may lose warranties.

Method 1: Official update via MIUI Updater (no PC)

This is the safest method, as the firmware is installed through the built-in Updater app, suitable for switching to a new version of MIUI without losing data (if the update is "over the air" - OTA), but it works only for official builds and will not allow you to install custom firmware.

Instructions:

1. Open the Update app (the icon with the arrow up) on your phone.
2. Click on the three dots in the top right corner and select Select Service Pack.
3. Specify the path to the downloaded firmware file (should have the name of the type) miui_DANDELIONGlobal_V12.5.1.0.RCDMIXM_... and extension.zip).
4. Confirm the installation and wait for the restart (it will take 5-15 minutes).

Important: if you download firmware from en.miui.com, choose the version for Redmi 9A (dandelion). Files for 9C or 9T will not work! Also check that the firmware version is not lower than the current one - downgrading the version (downgrad) through Updater is impossible.

Advantages of the method:

• ✅ Does not require PC and unlock the bootloader.
• ✅ Stores user data (if updated) OTA).
• ✅ Minimum risk of “bricking".

Disadvantages:

• ❌ You can't install custom firmware.
• ❌ It doesn't work to downgrade the version. MIUI.
• ❌ Sometimes updates come with a delay.

Method 2: Firmware through Recovery (with data storage)

If the update through MIUI Updater does not work (for example, due to corrupted system files), you can install the firmware through Recovery mode. This method is also official, but requires manual downloading of the firmware file and restarting to a special mode.

Suitable for:

• 🔄 Updates to the new version MIUI (if OTA doesn't come).
• 🛠️ Restore the phone after a crash (if it is still turned on).
• 📦 Installation of "clean" firmware (with deletion of user data).

Instructions:

1. Download the official firmware for Redmi 9A from en.miui.com (select Recovery ROM).
2. Rename the file to update.zip and move it to the root folder of the phone’s internal memory (not to folders like Download!).
3. Turn off your phone. Press both the power button and the volume button to enter Recovery.
4. In the Recovery menu, select the language (if you have an option), then:
5. After you complete the process, select Reboot to System.

Note: If you select the "Wipe Data" option in Recovery, all user data (photos, apps, settings) will be deleted! this step is only mandatory if the phone is unstable or the firmware requires a "clean" installation.

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Firmware through Recovery does not require unlocking the bootloader, but only works with official MIUI files. For custom ROMs, you need to use Fastboot or TWRP.

Method 3: Fastboot Firmware (complete reinstallation)

Fastboot Method is a "Heavy Artillery" for Redmi's Firmware 9A. It allows you to install any official firmware (including downgrading the version), but requires a PC, USB-It also erases all the data on the phone, so backup is mandatory.

What you need:

• 🖥️ Computer with Windows/Linux and installed Xiaomi drivers.
• 🔌 Original. USB-cable (cheap cables may not transmit data in Fastboot mode).
• 📦 Fastboot firmware ROM (file with the extension.tgz or.zip).
• 🔓 Unlocked boot loader (instruction below).

Step-by-step:

1. Unpack the downloaded Fastboot ROM to a folder on a PC (for example, C:\dandelion_fastboot).
2. Turn off your phone and press the power button + volume reduction to enter the Fastboot (the image of a hare in a hat-eared will appear).
3. Connect your phone to your PC and check for device detection by command: fastboot devices must display the phone serial number.
4. Run the firmware script: fastboot flash all or (for Windows): flash_all.bat
5. Wait for the completion (about 5-10 minutes) and automatic reboot.

If the process is interrupted by the remote error: device is locked, the bootloader is locked.

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If after firmware through Fastboot the phone is stuck on the MI logo for more than 15 minutes, reset via Recovery: press the power + increase the volume, select Wipe Data → Reboot.

How to unlock the bootloader on Redmi 9A

Without bootloader unlocking, you won’t be able to install custom firmware or downgrade the MIUI version via Fastboot. Xiaomi officially lets you unlock the bootloader, but the process requires a Mi Account and wait (usually 7-15 days).

Instructions:

1. Link your phone to your Mi Account (Settings → Xiaomi Account).
2. Go to Settings → About Phone → The MIUI version and tap it 7 times to activate Developer Mode.
3. Return to Settings → More → For Developers and Enable: Unlock OEM Debugging over USB
4. Download the Mi Unlock Tool from en.miui.com/unlock and run it on PC.
5. Log in to the same Mi Account as on your phone and connect your phone in Fastboot mode.
6. Press Unlock in the program. If you receive a message to wait, wait for the specified time (usually 168 hours) and try again.

⚠️ Note: once the bootloader is unlocked, all data, including photos and apps, will be deleted from the phone, and Xiaomi may also block the ability to re-block the bootloader on some firmware.

If the unlocking does not pass, check:

• 🔗 Phone and PC connected to one Mi Account.
• 📶 Mobile Internet or Wi-Fi enabled (to check Xiaomi servers).
• ⏳ You wait enough time (168 hours is exactly 7 days).

Installation of custom firmware (TWRP + Custom ROM)

Custom firmware like LineageOS or Pixel Experience gives Redmi 9A new features, a more recent version of Android and no MIUI ads. However, installing them is warranty-free and requires:

• 🔓 Unlocked loader.
• 🛠️ Installed custom Recovery (TWRP).
• 📦 Compatible firmware for the dandelion model.

Installation steps:

1. Download TWRP for Redmi 9A from twrp.me (see dandelion).
2. Install. TWRP Fastboot: Fastboot Flash Recovery twrp-3.7.0_9-0-dandelion.img fastboot boot twrp-3.7.0_9-0-dandelion.img
3. In TWRP, run Wipe → Format Data (this will delete everything, including internal memory!).
4. Copy a custom firmware file (e.g. lineage-18.1-20230610-UNOFFICIAL-dandelion.zip) to your phone via MTP to TWRP.
5. Install the firmware via Install → Select the file → Swipe to Confirm.
6. After installation, go to Gapps (if you need Google services) and Magisk (for root rights).

The following are the best features for Redmi 9A:

⚠️ Note: custom firmware can contain bugs, especially on budget devices like Redmi. 9A. Before installing, check the reviews on the forums (for example, 4PDA or XDA) Stability of a particular assembly.

Solving typical firmware errors

Even if you follow instructions, you can get errors, and here are the most common problems and solutions.

• 🚫 Mistake "This" MIUI So you're trying to install firmware that's not for your model. 9A) and download the correct file.
• 🔒 Error "Device is locked" in Fastboot bootloader is locked. Unlock it through Mi Unlock Tool (see section above).
• 🔄 The phone is stuck on the logo. MI After firmware, run Wipe Data in Recovery or flash your phone again through Fastboot.
• 📵 PC doesn't see phone in Fastboot mode Check drivers, try another USB-In Device Manager, the phone should be displayed as Android Bootloader Interface.
• 🔋 The phone does not turn on after the firmware Connect to charging on 30 If it doesn't work, run through Fastboot using the command fastboot flash all. -w (erase all data).

If none of these methods worked, please refer to the 4PDA or XDA Developers forums to indicate:

• The phone model (Redmi 9A)
• The firmware versions (before and after).
• The exact text of the error.
• The steps you took.

FAQ: Frequent questions about Redmi firmware 9A