How to Sweeten Xiaomi 9T: 3 Proven Ways With Detailed Instructions

Why do you want to use Xiaomi 9T and what are the risks?

Xiaomi Redmi 9T (codenamed lime) is a process that can solve many problems, from bugs in the system to completely reinstall MIUI after a crash. However, not all users understand that the wrong actions lead to a “brick” (complete failure) of the device or loss of warranty. This article will help you understand when firmware is really necessary and when it is better to get by with a standard update.

The main reasons for the Xiaomi 9T firmware are:

• 🔄 The device hung on the logo. MI or cyclically rebooted (bootloop")
• 🐢 The system is slowing down despite resetting settings
• 🔓 You need to delete the MI-account after buying a used phone
• 🆕 Desire to install custom firmware (e.g. Pixel Experience or LineageOS)
• 🔒 Recovery after failed "over-the-air" update"

But before you start, consider that the firmware through Fastboot or Recovery requires unlocking the bootloader, which erases all data and resets the settings to factory. If your goal is just to update MIUI to the latest version, use the built-in MIUI Updater (which we will discuss in the last section).

Preparation for firmware: what to do before the start

Incorrect preparation is the main reason for firmware failure. Before connecting the Xiaomi 9T to your computer, follow these steps:

1. Save important data. Fastboot or Recovery firmware formats internal memory. Use Mi Mover, Google Photos or manual copying on your PC.
2. Check the model of the device. Type in the Phone app code ##4636## and make sure that Redmi 9T (lime) is displayed.
3. The battery must be at least 60% charged, and when discharged during the process, the device may turn off.
4. Install drivers. For Windows, download the Mi Flash Tool and Qualcomm drivers (if they are not available, the system will not see the phone in Fastboot mode).

Also prepare:

• 🔌 Cable USB Type-C (original or certified) Cheap cables can interrupt the connection.
• 💻 Windows computer 10/11 (for Fastboot or with Linux/macOS (for ADB).
• 📥 Firmware for your model. Download only from official sources: Official site Xiaomi (choose version for lime) Xiaomi Firmware Updater (for stable and beta versions)

⚠️ Note: If you are using Xiaomi 9T With a locked bootloader, first unlock it through the Mi Unlock Tool. Without this, the Fastboot firmware will end in an error.

I've done a backup of data | Checked the device model (lime) | Charged the phone >60% | Installed the Mi Flash Tool | Downloaded the correct firmware-->

Method 1: Fastboot Firmware (complete reinstallation of MIUI)

This method is suitable for restoring a brick, installing an official firmware, or changing a region (for example, from Chinese to global), completely erasing data and reinstalling the system.

Step-by-step:

1. Turn off the phone. Press Volume down + Power to enter the Fastboot (the hare in the eardress cap will appear).
2. Connect Xiaomi 9T to the PC. in the Device Manager should appear Qualcomm HS-USB QDLoader 9008.
3. Unpack the downloaded firmware (file with extension.tgz) in the folder without Cyrillic.
4. Open the Mi Flash Tool, press Select and point the path to the firmware folder.
5. At the bottom, select Clean All or Clean All and Lock (if you want to lock the bootloader after you have firmware).
6. Press Flash and wait for completion (5-10 minutes). the phone will reboot automatically.

If the Mi Flash Tool is 0x80070002 or 0x8007001f, check:

• 🔌 Connecting the cable (try another port) USB)
• 📁 The path to firmware (should not be Cyrillic or gaps)
• 🔒 Is the boot loader unlocked (if not, unlock it)

Method 2: Firmware through Recovery (without PC)

If the phone turns on but is not running smoothly, you can flash it through Recovery without a computer, a method that stores user data (unless you choose to wipe data).

Instructions:

1. Download the firmware for Redmi 9T in.zip (not.tgz!) and move it to the root of the internal memory.
2. Turn off the phone. Press Volume up + Power to enter Recovery.
3. Select the language (if you have a choice), then Install update.zip to System.
4. Specify the path to the downloaded.zip file and confirm the installation.
5. After you complete the process, select Reboot to System.

If Recovery doesn't have Install update.zip, you have a stock recovery from Xiaomi.

• 🔄 Rename the firmware file to update.zip and repeat.
• 🔧 If it doesn’t work, install it via Fastboot (Type 1).

⚠️ Note: Firmware through Recovery will not change the region MIUI (For example, from Chinese to global.

💡

If after the firmware through Recovery, the phone is stuck on the boot for more than 15 minutes, perform a data reset (wipe data) in the same Recovery menu.

Method 3: Update via MIUI Updater (without data loss)

The safest method is to update over the air through the built-in System Update app, which is suitable for installing official MIUI updates without the risk of blinking.

How to update:

1. Open Settings → About the phone → System update.
2. Click on the three dots in the top right corner and select Select Service Pack.
3. Specify the path to the firmware file.zip (downloaded in advance).
4. Confirm the installation and wait for the reboot.

Advantages of this method:

• 📱 Does not require PC and unlock the bootloader.
• 💾 Stores all data and settings.
• 🔒 Safe for beginners.

However, consider the limitations:

• ❌ You can't downgrade the story. MIUI (update).
• ❌ It does not work if the system is damaged (bootloop).
• ❌ Not all firmware supports this method (e.g. customized firmware).

💡

Updating via MIUI Updater is the only officially supported Xiaomi way that does not deprive you of warranty.

How to Switch Custom Firmware (Pixel Experience, LineageOS)

Installing custom firmware (e.g. Pixel Experience or LineageOS) gives a clean Android without a MIUI shell, but requires an unlocked bootloader and installing custom Recovery (e.g., TWRP).

Step-by-step:

1. Unlock the bootloader through the Mi Unlock Tool (it will take 7-30 days to wait).
2. Install TWRP Recovery for Redmi 9T (lime) via Fastboot: fastboot flash recovery twrp.img fastboot boot twrp.img
3. In TWRP, run Wipe → Format Data (enter yes).
4. Transfer custom firmware and GApps files (if you need Google services) to your phone via MTP to TWRP.
5. Install the firmware, then GApps, and restart.

Popular custom firmware for Xiaomi 9T:

• 📱 Pixel Experience – Pure Android with Pixel features.
• 🔄 LineageOS - stable firmware without excess software.
• 🔥 crDroid – Balance between performance and functionality.

⚠️ Warning: Castom firmware may have camera bugs, NFC Check the reviews on the XDA-Developers forum before installing.

Frequent mistakes and their solutions

Even when following instructions, users encounter problems, and here are the most common errors and ways to correct them:

If after the firmware Xiaomi 9T does not SIM-map, check it out:

• 📶 Correctness of installed firmware (for example, global for lime_global).
• 🔧 Network settings in Settings → SIM-maps and mobile networks.
• 📡 Modem version (you can flash separately through Fastboot with the fastboot flash modem command) NON-HLOS.bin).

FAQ: Answers to Frequent Questions