Guides

How to check a used Xiaomi, Redmi or POCO phone

Updated September 27, 2026

Xiaomi, Redmi and POCO phones are cheap for their specs, which makes them popular second-hand. It also means you'll run into imported phones with a swapped ROM, phones still tied to the previous owner's Xiaomi account, and a few models known for failing mainboards. This guide follows the order to check things in, and takes about 15 minutes.

Tip: open soimay.com in Chrome on the phone you're checking. The steps that apply to every Android phone are in how to check a used Android phone; this guide covers what's specific to Xiaomi.

1. Xiaomi account and Google account

Xiaomi phones have two locks. If either account of the previous owner is still on the phone, it will lock after a factory reset:

  • Xiaomi account (Mi Account): go to Settings › Xiaomi Account (usually the top line). It must be empty, and Find device must be off.
  • Google account: go to Settings › Accounts & sync; none of the seller's accounts should be left.

The safest option is to have the seller sign out of both and factory reset in front of you. If the phone says "This device is locked" when it starts, don't buy it: a Xiaomi account lock can't be removed legitimately without the owner.

2. Official, imported, or a swapped ROM

Go to Settings › About phone and look at the HyperOS version (or MIUI on older phones). The letters at the end tell you which ROM it is, for example:

  • MIXM: global version.
  • EUXM: European version.
  • CNXM: Chinese domestic version, which usually has no Google services preinstalled.

A Chinese-market phone running a global ROM, or a ROM with an odd name, has usually had its bootloader unlocked and a custom ROM flashed. Restart the phone: if the boot screen shows "Unlocked" or an open padlock, the software has been tampered with. Banking apps may refuse to run on it, and updates can break it.

Dial *#06# to show the IMEI and compare it with the SIM tray and the box.

3. The built-in CIT hardware menu

Xiaomi phones have a hardware test menu called CIT:

  • Dial *#*#6484#*#* in the Phone app, or
  • Go to Settings › About phone › Detailed info and specs and tap Kernel version five times (the wording can differ slightly between HyperOS versions).

CIT tests each part: screen, touch, speakers, microphones, sensors, fingerprint and vibration. It's useful, but the text is small and often English-only. Run the Soi Máy tests alongside it so you end up with a report you can share.

4. AMOLED screen

Most Redmi Note, POCO F and numbered Xiaomi models use AMOLED screens. Common problems:

  • Burn-in: show a grey screen and look for faint shadows of the keyboard or navigation bar.
  • Lines across or down the screen, especially green ones. They tend to get worse over time.
  • Cheap replacement screens: dimmer, tinted, and the in-display fingerprint stops working.
Dead pixel, backlight bleed and burn-in testFind dead or stuck pixels, backlight bleed, burn-in and lines on a phone or laptop screen. Eight full-screen colours, free, no app to install.

If the phone is sold with a 120 Hz screen, measure the refresh rate. Xiaomi often defaults to 60 Hz or "auto" to save battery, so switch to 120 Hz in Settings › Display before measuring.

5. Touch and fingerprint

Fill the grid to find dead areas, then enroll a new fingerprint of your own.

Touch screen test: dead zones and ghost touchesSwipe to fill a grid of cells and spot dead touch zones or ghost touches on a phone or tablet. Runs full screen, free.

Many POCO and Redmi phones put the fingerprint sensor in the side power button. If the button is worn or loose, recognition gets slow. Press it a few times and check it clicks evenly.

6. Battery and fast charging

  • Many HyperOS phones have Settings › Battery › Battery health, but not all; it depends on the model and ROM.
  • Plug in the phone's original charger and cable: the lock screen should show the fast charging animation (Turbo Charge, HyperCharge). If it doesn't, the cable, charger or port has a problem.
  • Run the battery test for a few minutes to see how fast it drains.
Battery and charging port testSee the battery level, catch a loose charging port by plugging in and out, and watch how fast it drains. Plus where to read battery health.

7. Models known for mainboard failures

A few models have a reputation for mainboard failures after a couple of years: constant restarts, stuck on the logo, or losing signal. Many owners report it on the POCO X3 Pro and POCO X3 NFC. For these:

  • Ask whether the board has been repaired, and where.
  • Run the CPU test for a few minutes to warm the phone up: shutting down or restarting midway is a bad sign.
  • Use the phone continuously for at least 10 minutes before deciding.

8. Cameras, speakers, signal

  • Open every camera in the Camera app and in the camera test. Phones with several cameras often have one broken that the seller doesn't mention.
  • Try the speakers and microphone, including the earpiece during a call.
  • Put in your SIM, make a call, and try mobile data and Wi-Fi. Imported phones can lack some bands used by local carriers, so signal may be weaker than on an official model.

When you're done

Save the results as a PDF or a link and QR code on the Results page. The things you check by eye (accounts, IMEI, ROM version) are in the manual checklist.

More guides