Xiaomi Poco X3 firmware: official and custom methods

Why do Poco X3 owners decide to reflash their smartphone?

The Xiaomi Poco X3 is still a popular device years after its release due to its balance of performance and price. However, over time, users face typical problems: the system begins to “brake”, the battery goes down faster, and MIUI updates come with a delay or even stop.

Some choose the official global firmware for stability, others experiment with custom builds (like LineageOS or Pixel Experience) for pure Android without excess software, and still others want to downgrade the version of MIUI if the new one is raw. But regardless of the purpose, the firmware process requires preparation, otherwise the risk of getting a brick instead of a phone.

In this article, we will analyze all the current ways of firmware Poco X3 (surya and karna models), from unlocking the bootloader to installing TWRP and custom ROM.

Preparation for firmware: what to do before the beginning

The firmware is not a push and forget. On a Poco X3 with a locked bootloader, the first step is always the same: unlock through the Mi Unlock Tool. Without that, neither the Fastboot nor the custom Recovery will install. But even if the bootloader is already unlocked, preparation is required.

Here's the checklist before the firmware:

Make backup data (photos, contacts, SMS)

Check the device model in Settings → About the phone

Download the correct firmware for your modification (surya or karna)

Charge your phone at least 60%

Install Xiaomi and ADB/Fastboot drivers on PC

Prepare. USB-cable (preferably original)

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Special attention is given to the choice of firmware. For the Poco X3, there are:

• 📦 Officially MIUI (stable and beta versions – downloaded from the official website.
• 🔧 Custom recovery (TWRP) — installing informal ROM.
• 🤖 Custom firmware (AOSP, LineageOS, Pixel Experience – require an unlocked bootloader and TWRP.

⚠️ Attention: If your Poco X3 purchased in China (version for the domestic market), firmware global MIUI It can block the network. Check the model in Settings. → The phone. → Model!

Method 1: Fastboot Firmware (official MIUI)

This is the most reliable method for installing stock firmware from Xiaomi, suitable if you need:

• 🔄 Return to the factory version after the custom ROM.
• 🐌 Fix the “lags” and errors of the current firmware.
• 🔒 Resolve problems after a failed "over-the-air" update».

Instructions:

1. Download Fastboot firmware for your model (surya or karna) with Xiaomi Firmware Updater.
2. Unpack the archive in a folder on your PC (the way without Cyrillic!).
3. Turn off the phone and press Volume Down + Power to log into the Fastboot.
4. Get Poco on. X3 PC and run the file flash_all.bat (for Windows or flash_all.sh (for Linux/Mac).
5. Wait until the phone is finished (the phone will reboot automatically).

It takes 5-10 minutes, and if you have an anti-rollback error, you're trying to install an older version of MIUI than you already have.

⚠️ Warning: Once you've run your Fastboot, all the data will be erased! If you want to save your files, backup in advance.

Method 2: Install custom firmware through TWRP

If you want pure Android without MIUI shells, or if you want to experiment with alternative ROMs, you'll need TWRP Recovery, which is more complex, but it's more powerful.

Steps:

1. Unlock the bootloader through the Mi Unlock Tool (instruction below).
2. Download TWRP for Poco X3 from the official website (choose the version for surya or karna).
3. Install. TWRP Fastboot: Fastboot Flash Recovery twrp-3.7.0_12-surya.img fastboot reboot recovery
4. In TWRP, make a backup of the current firmware (Backup option).
5. Sweat through custom ROM (like LineageOS) by formatting the System partition.

Popular custom firmware for Poco X3:

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Before installing custom ROM, check for feedback on forums (such as XDA or 4PDA).Some builds may not support NFC or cameras at full capacity.

How to unlock the bootloader on Poco X3

Without unlocking the bootloader, neither the Fastboot firmware (except the official one) nor TWRP will be installed. Xiaomi has made the process more complicated in the latest versions of MIUI, but you can get around the restrictions.

Step-by-step:

1. Link your Mi Account to your phone in Settings → Xiaomi account.
2. Activate Developer Options (7 times click on the MIUI version in About Phone).
3. Enable OEM Unlock and USB Debugging in Settings → More → For Developers.
4. Download Mi Unlock Tool from the official website.
5. Launch the utility on your PC, log in to your Mi Account and connect your phone in Fastboot mode.
6. Press Unlock and wait until it is completed (it may take up to 72 hours to wait).

⚠️ Note: If a Couldn't unlock error occurs when unlocking, try: Use another USB-Disable antivirus on PCs. wait 3-5 days (Xiaomi sometimes blocks unlocking for new accounts).

Yeah, long ago.|Yeah, but I had to wait 72 hours.|No, I'm just planning.|No, I'm afraid to "brick" the phone.-->

Typical Firmware Errors and How to Fix Them

Even if you follow the instructions, something can go wrong. Here are the most common problems and solutions.

• 🔴 Phone does not turn on after firmware ("brick") Reason: wrong firmware for the model or interrupted process. Solution: run the official Fastboot firmware through the Mi Flash Tool in Clean All mode.
• 🔄 Bootloop: kernel or module conflict. Solution: go to TWRP, make a Wipe → Format Data and reinstall firmware.
• 📵 No network after firmware Reason: firmware is incompatible with modem Solution: run separately modem and firmware via Fastboot.
• 🔋 Fast battery discharge Cause: battery calibration incorrect. Solution: TWRP Choose the Wipe → Battery Stats.

If the phone doesn’t respond at all (the indicator doesn’t burn, doesn’t vibrate), try:

1. Connect to charging for 30 minutes.
2. Press Loudness down + Power for 20-30 seconds.
3. Squeeze through EDL-Mode (requires an authorized Xiaomi account or boxing).

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90% of the Poco X3 bricks are recovered via Fastboot or EDL. The main thing is not to panic or try to flash on top of the broken system.

How to return the official firmware after custom

If the custom ROM experiment failed or you want to sell your phone, you can return stock MIUI in two ways:

1. Through Fastboot (recommended): Download the official Fastboot firmware. Unpack and launch flash_all.bat. After the reboot, the phone will be like new (with all locks Xiaomi).
2. Through TWRP (if Fastboot is not available): Download MIUI Recovery ROM (a file with the.zip extension). In TWRP, select Install and run the archive. Make Wipe Dalvik/Cache.

After returning to MIUI:

• The loader will be automatically locked.
• You'll have to re-unblock it if you want to install custom firmware.
• All data will be erased (except internal memory if the data is not formatted).

FAQ: Frequent questions about Poco X3 firmware