Buying a Xiaomi smartphone is a big decision, especially if you’re buying a used device or buying it in unofficial stores. Even new devices out of the box can have hidden defects, fake products or software jambs that will show up after a week of use. This article will help you avoid disappointment: it’s a collection of all the critical checks that you need to do before paying, from visual inspection of the case to deep testing of iron and software.
Xiaomi smartphones are very maintainable and have spare parts available, which are both plus and minus. On the one hand, even after a serious breakdown, the device can be restored for pennies. On the other hand, fraudsters actively use this, passing off repaired devices for new ones, replacing original components with cheap ones. We will tell you how to distinguish the real Xiaomi from a fake, check the history of the device and identify hidden problems that sellers often keep silent.
The guide takes into account the nuances for all popular series: Redmi Note, POCO, Mi and Black Shark. And if you already own a smartphone, at the end of the article you will find a checklist to check after purchase - it will help make sure that you are not cheated.
1. Originality Check: How to distinguish the real Xiaomi from the fake
Xiaomi fakes are less common than iPhones or Samsungs, but they are — especially among low-end models like the Redmi 9A or POCO M3. Fraudsters copy not only the look, but also the firmware, so visual inspection is not enough. Here are 4 reliable ways to check the originality:
- 🔍 IMEI on the box and under the battery (or in the slot) SIM) must coincide IMEI. You can check it out at IMEI.info, the original Xiaomi will display the model, year of release and country of manufacture. If the site shows "Unknown" or the data does not match the box, you have 100% fake.
- 📦 Box and trim. The original packaging Xiaomi has: matte coating, clear logo printing without blurring, hologram with a changing pattern when tilted. Inside must be documentation in Chinese / English, proprietary cable (with a logo on the connector) and power adapter (if it is provided by the model).
- 🤖 Firmware and MIUI. Go to Settings. → The phone, the version. MIUI The fakes must conform to the model (check on the official website.
- 🔧 The original Xiaomi has a sticker with a battery (or back cover) under the battery. QR-Scan it, it should lead to Xiaomi support page with device data.
If the seller refuses to show the box or allow the scan QR-The codes are a reason to be wary, especially the Redmi Note 10 Pro models and the ones that are often faked. POCO X3 Pro because of their popularity. You can use an app to check it out. AIDA64 (Available on Google Play: It will show the real-life characteristics of iron that should match the claims made on Xiaomi’s website.
⚠️ Note: Some vendors intentionally delete data on IMEI Or they're going to refashion the device to hide its origin, and if you check it with *#06#, it's not showing the right thing. IMEI (For example, all zeros – the smartphone is either fake or was in a service center with violations.
External inspection: what should alert you during a visual inspection
Even if the smartphone is original, it could have been repaired or dropped, and a body and screen inspection can help identify hidden defects.
- 🔦 Scratches and chips. Look at the frame and back panel from different angles. Deep scratches on the aluminum frame (in models Mi 11 or Redmi). K40) They talk about falls. Plastic cases (Redmi 9, POCO M4) Check for deformities - they could crack on impact.
- 📱 Screen. Turn on a white background (for example, opening Notes) and illuminate with a flashlight at an angle. Microcracks on the glass are visible only in this lighting - they manifest as thin spiders. Also check the oleophobic coating: if fingers slide with difficulty, it is no longer there (this is a sign of glass replacement).
- 🔊 Speakers and microphones. Blow through the speakers' holes -- if you hear a crunch or the air passes too easily, maybe the grid is damaged. Microphones check by recording voices in a quiet room: background noise or muffling indicate a defect.
- 🔋 Insert the charging cable into the port. USB-C — It has to come in tightly, without backlash, and if the connector is wobbling, it's going to have to be changed soon. SIM-map: he shouldn't hang around.
Notice the buttons: they have to be pressed with a clear click, without getting stuck. If the power or volume button is soft, it's either been repaired or it's about to break. IR-Check with a blaster (e.g. Redmi Note 11) through the Mi Remote app – if the remote does not catch the signal, the blaster is faulty.
Screen Testing: How to Identify Broken Pixels and Sensor Problems
The screen is the most expensive component of a smartphone, and its defects are not always noticeable on a cursory examination.
- Color tests. Open the Screen Test app and turn on the red, green, blue and black screens sequentially, with black backgrounds showing broken pixels (bright spots), colored ones showing spots or uneven backlighting.
- Touch test. In the same app, select Touch Test. Swipe your finger around the screen, the line should be flat, without tearing. Pay special attention to the edges: often after changing the glass, the touch works poorly.
- Autobrightness. Turn on automatic brightness control (Settings → Display → Autobrightness) and cover the light sensor (near the front camera). The screen should go out. If the brightness does not change, the sensor is defective.
For models with AMOLED-Check for burnout with screens (such as Xiaomi 12 or Black Shark 5): display a monochromatic background (gray or green) and look at it from an angle. If you can see the contours of previous images (such as navigation bars), the screen is already worn out. It should not flicker or display artifacts.
⚠️ Note: Some Xiaomi smartphones (especially after updates) MIUI 13+) There's a ghost touch bug, and the screen spontaneously responds to touch, and to check that, leave your phone on the table with the screen on for 5 minutes. If you get a random tap, it's a software bug that's treated by resetting your settings.
| Screen defect | How it manifests | Can we fix it? |
|---|---|---|
| Broken pixels | Bright dots on a dark background | No (only screen replacement) |
| Burn-in (burn-in) | The contours of icons are visible on a monotonous background | Partially (calibration in service) |
| Uneven lighting | Yellow spots on the edges | Yeah (backlight replacement) |
| Ghost touches | Self-pushing | Yes (reset or firmware) |
4.Battery check: how to find out the real wear and tear and operating time
The battery is the second most important component after the screen, and even if the smartphone is new, it could have been in storage for years, losing capacity.
- 🔋 Code. USSD. Type in ##4636###, select Battery Information. Health (or Battery Health) should be above 90%. If below, battery is worn out.
- 📊 AccuBattery. Install it from Google Play and charge your phone to 100%. The app will show real capacity in mAh and the degree of wear. For example, if the Redmi Note 10 Pro displays 4200 mAh instead of the stated 5020 mAh, the battery lost 16% of capacity.
- ⚡ Charging test. Connect the original adapter and record the charging time from 0 to 100%. In modern Xiaomi with Fast Charging, it takes 1-1.5 hours. If longer, either the adapter is faulty or the battery has degraded.
Notice the bloating of the battery: put the phone on a flat surface with the screen up. If it swings or the back cover moves away, the battery is swelling (this is dangerous!). Also check if the screen moves away from the body at the edges - this is another sign. In models with a fixed battery (POCO F3, Mi 11 Lite), bloating can manifest as a "slapping" rear panel when pressed.
What to do if the battery is blown?
If the seller claims that the battery is “virtually new,” ask for a charge history in Settings → Battery → Battery Use. It shows discharge graphs from recent days. A sharp jump or a quick discharge (for example, from 100% to 80% in 30 minutes) indicates a malfunction.
5. Camera diagnostics: how to identify software and hardware defects
Xiaomi cameras are often the victims of unscrupulous sellers: they can be repaired by handicrafts, replaced with cheap modules or simply not to twist the screws.
Take a photo on the main camera in bright light
Test the zoom (if any)
Take a video with stabilization enabled
Check the front camera in portrait mode
Take a photo in a dark room with the night mode turned on-->
Main camera:
- 📸 Take a photo at maximum resolution (in Camera Settings) → Enlarge the picture on the computer - there should be no blurs or artifacts (colored dots).
- 🔍 Check autofocus: point the camera at text from 20 cm away, it should focus quickly. If the focus floats, the camera module is damaged.
- 🌃 Turn on Night Mode and take a picture of the dark corner of the room. The real Xiaomi should draw details, not just brighten the picture.
Front camera:
- 👤 Take a selfie with Portrait Mode on, and the contours of the face should be clear, without cutting hair or ears.
- 🎥 Record the video and look at the smoothness. If the image twitches, it's a stabilization problem.
Pay special attention to the module with multiple cameras (for example, the Redmi Note 11 Pro+ has four of them), you can check the performance of each in manual mode (Pro Mode), switching the lenses. If one of the cameras does not focus or gives a green / purple shade, it is either repaired or it is factory defective.
⚠️ Attention: Some vendors deliberately disable additional cameras in the firmware to hide their malfunction.To check this, install the Camera app MX — It shows all available modules, even if they are hidden in a standard application.
6.Iron testing: processor, memory, sensors
Hidden iron problems don’t appear immediately, but they can make your smartphone unusable. Use a combination of built-in tests and third-party utilities to check:
- 🖥️ Processor and memory: Install AnTuTu Benchmark or Geekbench. Compare the results with the references for your model (you can find them on GSMArena%+ — The processor may be overheating or trottling due to wear.
- 📱 RAM: Open some heavy applications (like Genshin Impact) + Chrome with 10 tabs if the phone starts to "lay down" or closes the background processes — RAM faulty or insufficient (relevant for models with 4 GB of RAM).
- 🌡️ Overheat. CPU Throttling Test (available on Google Play) If the processor temperature exceeds 70 after 10 minutes of the test°C, and the frequency drops below 50% - the cooling system is faulty (thermopaste may have dried up).
- 🧲 Sensors. You can check them through the engineering menu: enter ##6484## (on some models ##64663##). In the sensor list, everyone should display values, not "N/A". Especially important: Accelerometer (turning the screen) Gyroscope (for games and games) AR) Compass (navigation) Approach sensor (turning off the screen during a call)
If your smartphone turns off when you're loading (like playing or shooting a video), it's a sign of power or processor problems, and a common cause is a faulty charging controller that can't handle the load, and you can check this by plugging your phone into charging and running 3DMark. If you shut down after 5 minutes of testing, you need repairs.
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If the vendor refuses to allow the installation of test applications, suggest that you check the hardware through the built-in diagnostic menu. To do this, type ##4636## and select Testing, which provides basic screen, camera and sensor checks without installing third-party software.
7. Software and device history check
Even if the hardware is fine, the smartphone could have been in the hands of fraudsters who changed IMEI, firmware or account data.
- 🔐 Link to Mi Account. Go to Settings → Xiaomi account: If the phone is tied to someone else's account, the seller must untie it to you (a password is required). If it refuses, the smartphone may be blacklisted (stolen).
- 📱 Update history. In Settings → The phone. → If the smartphone hasn't been updated for more than a year, either it hasn't been used or the firmware is pirated.
- 🛠️ Reset to factory settings. ask the seller to make a reset (Settings) → Additionally. → After rebooting, check if a password request from the previous owner appears (meaning Find My Device was not disabled).
- 🕵️ Check for "gray" imports. IMEI If the Country box indicates India or China and the seller claims that the phone is "European" is a hoax, such devices may not support local LTE-ranges.
Check the operation of all wireless modules:
- 📶 SIM-Cards: insert two cards (if supported) and check if the network each catches. On some "gray" Xiaomi, the second slot can only work in mode 2G.
- 📶 Wi-Fi and Bluetooth: Connect to a 5GHz network (if the router supports) and check speed through Speedtest. Bluetooth test file transfer between devices.
- 📍 GPS: Turn on geolocation and open Google Maps. The accuracy of the definition should be within 5-10 meters. GPS faulty.
⚠️ Note: Some vendors install custom firmware on Xiaomi smartphones (such as LineageOS) to hide the history of the device. → About the phone: if the version MIUI missing or listed an unknown build — unofficial firmware. This deprives you of warranty and can lead to problems with updates.
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If your smartphone was bought in China or India, check the support of the Russian LTE-Many of the “gray” Xiaomi does not work with the bands 700 MHz (Band 28), which are used by Russian operators.