- Aug 3, 2025
- 338
- 0
The Xiaomi Mi A1 (codename `tissot`) is a truly historic device. Released in 2017, it single-handedly revived Google's **Android One** program, pairing Xiaomi's excellent, reliable hardware with a pure, clean, stock Android experience. It was a massive global success and remains a beloved classic for enthusiasts.
However, its legacy is tied to its Chinese-market twin, the MIUI-based Mi 5X (`tiffany`). The single most common and fatal mistake owners make is attempting to flash MIUI firmware onto the Mi A1, a process which causes a permanent hard brick. This guide is exclusively for the Android One **Mi A1 (`tissot`)**.
In 2025, its official support has long ended with **Android 9 Pie**. This restoration manual is for the hobbyists and long-time owners who want to restore this classic to its final, stable official state, either to preserve it, unbrick it, or create a clean foundation for the vast world of custom ROMs.
Why You Might Need to Flash Your Mi A1
For the Mi A1, flashing is about restoration, safety, and continued customization.
Quick Device Overview (Codename: tissot)
Required Tools & Downloads
Before you start, gather the firmware and the correct tools for an Android One device. Note that Mi Flash Tool is not used.
Flashing Methods
Method 1: Flashing the Official Stock Android ROM (Fastboot Script Method)
This is the standard, official method for flashing a stock Android One ROM. **It does not use Mi Flash Tool.**
➡ Your phone will reboot automatically into a clean, stable Android 9 Pie system.
Method 2: Installing a Custom Recovery (TWRP)
This is the gateway to the massive custom ROM community for the Mi A1.
➡ With TWRP installed, you can now flash hundreds of custom ROMs and keep your Mi A1 alive with modern software.
FAQs
Q1: Can I install MIUI on my Mi A1?
While it is technically possible for very advanced users with complex, high-risk procedures, it is **strongly not recommended**. The easiest and most common way to permanently kill a Mi A1 is to try and flash MIUI firmware on it. It is best to embrace its identity as an Android One device.
**Q2: Is the Mi A1 safe to use in 2025?**
No. The official software has not received security updates in over five years and is running a very old version of Android. It is a major security risk and should only be used for offline tasks or on a network you trust, with no sensitive personal data on the phone.
**Q3: What are A/B partitions?**
The Mi A1 has two sets of system partitions (A and B) for seamless updates. When you get an official update, it installs to the inactive partition in the background. On reboot, the phone simply switches to that partition. For flashing, you just need to be mindful of booting directly into recovery after flashing it to prevent the system from overwriting it.
**Q4: Can I get Android 10, 11, or newer?**
Not officially. However, the Mi A1 has a legendary custom ROM community. You can find stable, unofficial builds of many newer Android versions on forums like XDA-Developers, which is the best way to continue using this phone with modern, more secure software.
Troubleshooting & Common Errors
However, its legacy is tied to its Chinese-market twin, the MIUI-based Mi 5X (`tiffany`). The single most common and fatal mistake owners make is attempting to flash MIUI firmware onto the Mi A1, a process which causes a permanent hard brick. This guide is exclusively for the Android One **Mi A1 (`tissot`)**.
In 2025, its official support has long ended with **Android 9 Pie**. This restoration manual is for the hobbyists and long-time owners who want to restore this classic to its final, stable official state, either to preserve it, unbrick it, or create a clean foundation for the vast world of custom ROMs.
- ✔ A critical warning about the Mi A1 (`tissot`) vs. the Mi 5X (`tiffany`)
- ✔ Download links for the final official stock Android 9 Pie firmware
- ✔ A guide to the correct flashing method for Android One devices (No Mi Flash Tool)
- ✔ A link to a working TWRP custom recovery and all essential tools
- ✔ Instructions on how to revive this piece of Android history
Why You Might Need to Flash Your Mi A1
For the Mi A1, flashing is about restoration, safety, and continued customization.
- Unbrick from a Failed MIUI Flash Attempt → This is the most critical reason. If you've tried to flash Mi 5X firmware and your phone is now bricked, this guide is your last hope for software recovery.
- Restore to Pure, Stock Android → If you've been experimenting with custom ROMs and want to return to the clean, official Google experience, this is the way.
- Fix Bugs or Bootloops → The definitive method for fixing a device that is stuck on the Android One logo or caught in a bootloop after a failed update.
- Create a Clean Base for Custom ROMs → The Mi A1 has a legendary custom ROM scene. Flashing the final stock Android 9 firmware provides the updated modem and vendor files needed for modern custom ROMs to work correctly.
- Downgrade for Stability → Some users found the final security patches for Android 9 to be less stable. This major build is widely considered a reliable and solid base.
Quick Device Overview (Codename: tissot)
- Model: Xiaomi Mi A1
- Release Year: 2017
- Chipset: Qualcomm Snapdragon 625
- Display: 5.5” FHD LTPS IPS Display
- Key Feature: The first device in Google's revamped Android One program
- OS at Launch: Stock Android 7.1.2 Nougat
- Final Official OS: Stock Android 9 Pie (End of Life)
- Codename: tissot
EXTREME WARNING: This firmware is for the Mi A1 (codename `tissot`) ONLY. It runs stock Android. DO NOT attempt to flash MIUI firmware from the Mi 5X (codename `tiffany`) on this device. This is not a "conversion"; it is an irreversible process that will cause a permanent, unrecoverable hard brick due to incompatible partition layouts.
Required Tools & Downloads
Before you start, gather the firmware and the correct tools for an Android One device. Note that Mi Flash Tool is not used.
| Tool / File | Purpose | Download Link |
|---|---|---|
| ADB & Fastboot Platform-Tools | The official Google toolset for Fastboot flashing. | Download from Google |
| Xiaomi USB Drivers | Ensures your PC can communicate with the phone. | Driver Pack |
| Mi Unlock Tool | Required to unlock the bootloader before first flash. | Official Unlock Page |
| Official Fastboot ROM (Android 9) | Global Stable Stock Android 9 Pie | V10.0.9.0.PDHMIXM |
| Custom Recovery (TWRP) | Gateway to installing custom ROMs. | Official TWRP for Tissot |
Flashing Methods
Method 1: Flashing the Official Stock Android ROM (Fastboot Script Method)
This is the standard, official method for flashing a stock Android One ROM. **It does not use Mi Flash Tool.**
- Unlock Bootloader: If you haven't already, you must unlock your device's bootloader using the Mi Unlock Tool. This will wipe your data.
- Extract Firmware: On your PC, extract the downloaded Android 9 `.tgz` firmware file twice using a tool like 7-Zip until you have a folder.
- Prepare Tools: Download and extract the ADB & Fastboot Platform-Tools. For simplicity, copy all the files from the platform-tools folder (like `fastboot.exe`) and paste them directly into the extracted firmware folder from the step above.
- Boot into Fastboot Mode: Power off your Mi A1 completely. Then, press and hold the Power + Volume Down buttons together until the Fastboot screen appears.
- Connect Your Phone: Connect the Mi A1 to your PC with a reliable USB cable.
- Run the Flashing Script: In the firmware folder, find the file named `flash_all.bat` (for Windows) and double-click it to run.
- A command prompt window will open and automatically execute all the necessary commands to flash the firmware. Do not close the window or unplug the phone until the process is finished.
➡ Your phone will reboot automatically into a clean, stable Android 9 Pie system.
Method 2: Installing a Custom Recovery (TWRP)
This is the gateway to the massive custom ROM community for the Mi A1.
- Boot into Fastboot Mode: Power off the phone and boot into Fastboot by holding Power + Volume Down.
- Flash TWRP: Flash the downloaded TWRP image file (`twrp-3.7.0_9-0-tissot.img`) using the command:
fastboot flash recovery twrp-3.7.0_9-0-tissot.img - Boot Directly into Recovery: This is a crucial step for A/B devices. Immediately after the flash command finishes, use the volume keys to select "Recovery Mode" on the Fastboot screen and press the power button. Alternatively, you can type fastboot reboot recovery. Do not let the phone boot into the Android system first.
➡ With TWRP installed, you can now flash hundreds of custom ROMs and keep your Mi A1 alive with modern software.
FAQs
Q1: Can I install MIUI on my Mi A1?
While it is technically possible for very advanced users with complex, high-risk procedures, it is **strongly not recommended**. The easiest and most common way to permanently kill a Mi A1 is to try and flash MIUI firmware on it. It is best to embrace its identity as an Android One device.
**Q2: Is the Mi A1 safe to use in 2025?**
No. The official software has not received security updates in over five years and is running a very old version of Android. It is a major security risk and should only be used for offline tasks or on a network you trust, with no sensitive personal data on the phone.
**Q3: What are A/B partitions?**
The Mi A1 has two sets of system partitions (A and B) for seamless updates. When you get an official update, it installs to the inactive partition in the background. On reboot, the phone simply switches to that partition. For flashing, you just need to be mindful of booting directly into recovery after flashing it to prevent the system from overwriting it.
**Q4: Can I get Android 10, 11, or newer?**
Not officially. However, the Mi A1 has a legendary custom ROM community. You can find stable, unofficial builds of many newer Android versions on forums like XDA-Developers, which is the best way to continue using this phone with modern, more secure software.
Troubleshooting & Common Errors
- Bricked after attempting to flash MIUI: This is the most common fatal error. Recovery from this specific brick is extremely difficult and often requires advanced EDL mode (test point) flashing, which can be very risky. Always stick to AOSP-based ROMs for `tissot`.
- The `flash_all.bat` script window closes instantly: This is a driver issue. Ensure your PC recognizes the device in Fastboot mode by opening a command prompt in the folder and typing `fastboot devices`. If it doesn't show up, reinstall the drivers.
- "Device is corrupt" message on boot: This is a normal security warning on Android One devices with an unlocked bootloader. It is safe to ignore, and your phone will boot into the system after a few seconds.
- Wi-Fi not working after flashing a custom ROM: This often means you need to flash the latest official stock firmware first (using Method 1 in this guide) to update your modem and other low-level firmware partitions before flashing the custom ROM.
