Reflashing Xiaomi Redmi 9A: official and custom methods

Xiaomi Redmi 9A remains one of the most popular budget smartphones even years after its release. However, over time, standard MIUI firmware can start to slow down, and updates from the manufacturer stop coming. Flashing the device allows you not only to return to its former performance, but also to install a fresh version of Android, fix system bugs or even switch to custom firmware like LineageOS.

In this guide, we will discuss all the current ways to reflash Redmi 9A (codename dandelion): from the official update via Recovery to the complete reinstallation of the system through Fastboot. Particular attention will be paid to unlocking the bootloader - without this step custom firmware simply not install, and you will learn how to avoid common errors such as anti-rollback or brick device.

Preparation for firmware: what you need to know before you start

Flashing is not just pressing a few buttons, but doing the wrong thing can turn your Redmi 9A into a brick that won't even turn on.

• 🔋 Battery charge at least 60 percent, and the firmware process can take up to 30 minutes, and a sudden power outage will interrupt it.
• 📥 Backup. Firmware erases all files in the device's memory (except memory card). Use Mi Cloud or Google Photos for backup.
• 🖥️ Windows computer 10/11. Fastboot firmware will require a PC with Qualcomm drivers installed and ADB.
• 🔗 Original. USB-Cheap cables can't transmit data, which will cause a failure.

If you plan to install custom firmware (e.g. Pixel Experience or Havoc-OS), note that it is imperative to unlock the bootloader. Xiaomi blocks this feature by default, and the unlocking process can take up to 7 days (due to company policy).

⚠️ Note: Install firmware with a lower version of Android (downgrade) on Redmi 9A It's a risk of anti-rollback protection. MIUI 12 after MIUI 13, the device will lock. Check the firmware version before installing it!

Method 1: Update via Recovery (without a computer)

The easiest and safest method is to upgrade through a standard recapvery, which is suitable if:

• 📲 You want to update. MIUI before the last official.
• 🔄 You already have a stock firmware installed without modifications.
• 🚫 You are not planning to install custom firmware.

This method will require only the smartphone itself and a pre-downloaded firmware file in.zip format. Download it only from the official Xiaomi website (select the Redmi 9A model with the code name dandelion).

Step-by-step:

1. Download the firmware and move the update.zip file to the root directory of internal memory (not to folders!).
2. Turn off the phone, then press Power + Volume up to enter Recovery Mode.
3. In the Recovery menu, select Install update.zip to System (use volume buttons for navigation, power for confirmation).
4. Confirm the installation and wait until it is completed (usually takes 5-10 minutes).
5. After the reboot, the device will be with a new firmware.

⚠️ Warning: If E: Signature verification fails in the Recovery, the firmware file is corrupted or not intended for your model. MD5.

Downloaded official update.zip for Redmi 9A (dandelion)| File moved to memory root (not folder)| Battery charged at least 60% | Backup of important data-->

Method 2: Fastboot Firmware (complete reinstallation)

Fastboot firmware is a clean installation that deletes all data and replaces all partitions on the device.

• 🔧 You want to return the smartphone to the “factory” state.
• 📉 The device does not turn on or is stuck on the Mi logo.
• 🔓 You are planning to unlock the bootloader for custom firmware.

This method requires a computer with the Mi Flash Tool and ADB/Fastboot installed. You also need to download Fastboot firmware for Redmi 9A (file with the extension.tgz or.zip).

Instructions:

1. Unpack the archive with firmware in a folder without Cyrillic characters (for example, C:\dandelion_fastboot).
2. Turn off your phone and press Power + Volume down to enter Fastboot Mode (a hare in a hat-eared hat will appear on the screen).
3. Connect the device to the PC via USB.
4. Launch the Mi Flash Tool, press Select and specify the path to the firmware folder.
5. At the bottom, select Clean All mode and press Flash.
6. Wait until it is completed (about 5-15 minutes).

If the Mi Flash Tool gives an error critical partition flashing is not allowed, then the bootloader is locked. To unlock it, follow the instructions in the next section.

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If the Mi Flash Tool doesn’t see the device, try reinstalling Qualcomm drivers manually through Device Manager (look for the device with an exclamation mark in the “Other Devices” section).

Unlock the bootloader on Redmi 9A

Without an unlocked bootloader, you won’t be able to install customized recaps (TWRP) or unofficial firmware. Xiaomi has made this process more complicated: it now requires a Mi Account binding and waiting for confirmation.

What you need:

• 📱 Mi Account associated with the device (at least 7 days ago!).
• 🖥️ Computer with Mi Unlock Tool (you can download it on the official website).
• 🔌 Cable USB Type-C (preferably original).

Step-by-step:

1. Turn on the phone Developer Options: go to Settings → About Phone → MIUI version and tap 7 times on the build number.
2. Back to Settings → Additionally. → For developers and activate OEM-unlocking and debugging USB.
3. Connect your phone to your PC, launch the Mi Unlock Tool, and log in to the same Mi Account as your phone.
4. If you see a message called Couldn't unlock. Try again after XX hours, you have to wait (usually 168 hours = 7 days).
5. After successful unlocking, the phone will restart with the cleared data.

⚠️ Attention: Unlocking the bootloader resets the device to factory settings! also some features (e.g. Mi Pay or Widevine) L1 for Netflix HD) They may stop working.

Installation of custom firmware (TWRP + Custom ROM)

If stock MIUI does not suit you, you can install alternative firmware, for example:

• 🤖 LineageOS – pure Android without Bloatware.
• 📱 Pixel Experience – firmware with an interface like Google Pixel.
• ⚡ Havoc-OS – customizable firmware with many functions.

This requires:

1. Unlock the bootloader (see previous section).
2. Install the custom TWRP recavator.
3. Switch a.zip file of custom firmware.

Installation of TWRP:

1. Download the last one. TWRP for dandelion from the official website (file) twrp-3.7.0_9-0-dandelion.img).
2. Rename it to recovery.img and place it in the folder with the platform-tools (where the ADB is installed).
3. Turn on Fastboot Mode on your phone and connect to your PC.
4. Enter the command: fastboot flash recovery.img fastboot boot recovery.img The phone will reboot to TWRP.

Installation of Custom ROM:

1. Download firmware (such as LineageOS) and GApps (Google services) in.zip format.
2. Move the files to a memory card or internal memory.
3. In TWRP, select Wipe → Advanced Wipe and select Dalvik, Cache, System, Data.
4. Press Install, select a firmware file and confirm the installation.
5. Repeat the step for GApps (if you need Google services).
6. Reset the device.

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Castom firmware may not support all of the features of Redmi 9A. For example, some builds do not have NFC or camera fully functioning. Before installing, read the feedback on the forums (4PDA, XDA).

Common mistakes and their solutions

Even when following instructions, there may be problems, and here are the most common ones and how to fix them:

If the device is stuck on the Mi logo after firmware, try:

1. Press Power + Volume up for 10-15 seconds for forced reboot.
2. If it doesn’t work, repeat the firmware through Fastboot in Clean All mode.
3. In extreme cases, use EDL Mode (emergency mode) and swipe through Mi Flash with the Flash All Except Storage tick.

How to return stock firmware after custom

If custom firmware is unstable or you want to return the warranty, you can roll back to the official MIUI.

1. Download Fastboot firmware for your region (for example, dandelion_global_images...).
2. Unpack the archive and launch the Mi Flash Tool.
3. Select Clean all and lock mode - this will block the bootloader and return the stock Recovery.
4. Connect your phone to Fastboot Mode and start the firmware.

After the reboot, the device will be like a new one, with the bootloader locked and the official firmware, and note that all data will be erased and some features (such as Root) will stop working.

⚠️ Warning: If you block the bootloader after installing custom firmware, the phone can turn into a brick. Always go back to the stock. MIUI pre-lock!

FAQ: Frequent questions about Redmi firmware 9A