Checking Xiaomi smartphone before buying: full checklist

Buying a new smartphone is always an exciting moment, especially if you choose a device from a popular brand like Xiaomi. However, the joy of buying a new smartphone can be overshadowed by defects that were not noticeable when you checked it at the store. In an environment where sellers often do not allow you to fully unpack the box or activate the device, it is important to know what nuances to pay attention to right in the sales hall.

In this article, we will discuss in detail the algorithm of actions that will help you avoid buying a defective instance or a restored device, you will learn what technical parameters require mandatory verification, how to quickly identify “broken” pixels and why IMEI-concording is a critical procedure for owners of the Android ecosystem.

Don't rely on a consultant's assurance that "all phones are the same." Statistics show that a certain percentage of devices have factory defects that are easier to exchange under warranty at the time of purchase than to undergo lengthy repair procedures later. Let's move on to practical steps.

Visual inspection of the body and configuration

The first thing that starts to check any gadget, including the flagship Xiaomi 14 series or the budget Redmi Note, is careful visual control. Even if the box is sealed, ask the seller to open it to inspect the device itself. Pay attention to the joints of the case: there should be no gaps, glue or back cover between the frame and the screen or the back cover. Any detachment can indicate poor build or, worse, unskilled repair.

Carefully inspect the connectors and ports. USB Type-C should be free of dust, pile or traces of oxidation. SIM-If you have a card or on the edges of the device, it is a sure sign that the phone was already in use. Also check the quality of the sticker with basic information on the back cover (if it is provided by the model): it should be glued flat, without bubbles and skews.

⚠️ Warning: If you see micro scratches or screws rubbing on the ends of the device near the charging port, refuse to buy these are clear signs of exploitation that the store may try to pass off as "transportation damage».

The kit is another important aspect. The box should have original accessories: cable, paper clip for tray extraction and documentation. Xiaomi cable usually has the brand logo on the plug and a tight braid. No charger in new models is normal practice, but the cable itself must be available.

• 📦 Check the integrity of the factory seals on the box.
• 🔍 Examine the lenses of the cameras for dust inside the glass.
• 🧱 Make sure the tray is for SIM-maps are colored to the body.

Authentication and reconciliation IMEI-code

One of the most critical procedures is to verify the unique device identifier. IMEI (International Mobile Equipment Identity) is your phone's passport. On the box, under the battery (if it's removable), and on the system menu itself, these codes must be completely identical. The mismatch of numbers may mean that you are trying to sell a device assembled from different parts or a phone listed as stolen.

For a quick check, dial the universal command *#06# in the Phone app. The screen will display a list of identifiers. In modern Xiaomi smartphones, there can be several of them if the device supports two devices. SIM-maps and has a module NFC. Compare those numbers to the ones on the box sticker, and any discrepancy, even one digit, is a reason to stop the deal immediately.

Additionally, you can check the status of the device on the official MI Verify website if the store has access to Wi-Fi. Type IMEI in the search box, and the system will show the date of activation and the rest of the warranty. If the phone is supposedly new, but the warranty began six months ago, you have a Refurbished device or used device.

Diagnostics of the display and sensor

The screen is the most expensive and fragile component of a smartphone. When buying devices with AMOLED or IPS arrays, you need to test for broken pixels and uniformity of backlights. Turn on the device and set maximum brightness. Open the white image and carefully examine the surface: there should be no black dots (broken pixels) or colored spots.

Then switch to black. This is especially important for screens with Always On Display technology. On a black background, you can clearly see the edges of the lights or the flashlight effect, when you see a glow in the center of the screen. For AMOLED matrices, black should be absolutely deep, indistinguishable from the frame of the case.

Checking the touchscreen is mandatory. In the Xiaomi engineering menu, which is called by the code # # #6484##, there is a Touchpanel test. Follow the instructions on the screen, swiping your finger through all areas of the display. The line should be continuous, without breaks and spontaneous jumps (so-called "ghost touches").

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Use the Tester app or online color checker services if the test doesn’t seem detailed enough on the engineering menu.

Testing of cameras, microphones and speakers

Multimedia capabilities are one of the reasons Xiaomi is so popular. In the engineering menu (CIT), select the Camera section. Take some pictures in good light and when there is a lack of light. Pay attention to the focus: it must be fast and accurate. If the camera is "sniffing," can't catch a focus, or makes extraneous noise (rattling) - this is a sign of a malfunction of the OIS module (optical stabilization).

Sound check is also mandatory. Turn on the recorder and record your speech, then play. The sound must be clean, without wheezing or coding. To check the main speaker and the conversational earpiece, there are appropriate items in the test menu that play tunes. Make sure the volume is adjusted smoothly, without jumping.

⚠️ Warning: Be sure to check the vibrator. The vibration should be clear and short ("tic"), not a long hum. rattling of the body when vibrating indicates poor assembly or unstuck battery.

Don't forget to test the sensors. In the same engineering menu, there's a Sensor section. Check the accelerometer, the proximity sensor (close the top of the screen with your hand - it should go out), and the fingerprint scanner. The scanner should read the fingerprint the first or second time, without delay.

Evaluation of autonomy and charging operation

Although it is difficult to do a full battery test in the store, you need to do a basic check. From the CIT menu, select Battery, which shows the status of the battery, its actual capacity and the number of charging cycles, and for a new device, the number of cycles should be minimal (usually 0-5 cycles, since the factory is calibrating).

Connect the original charger. The screen should respond to the connection instantly. If the phone supports fast charging HyperCharge or Quick Charge, the appropriate animation should appear on the screen. If charging is slow or contact is lost when the cable moves lightly, the connector is a problem.

If the phone warms appreciably in the area of the processor or battery when switched on and set up, this may indicate problems with the heat paste or a defect in the power controller.

Checking communication, Wi-Fi and navigation

A smartphone should be able to hold the network with confidence. SIM-You can check the signal level, try to make a test call, and the voice of the person should be heard clearly, without interference and "quaking". Check the operation of the second microphone (noise reduction) - for this, during a conversation, press the lower part of the phone with your hand, the background noise should not disappear completely, but should be filtered.

Wi-Fi and Bluetooth testing is best done if the store has an open network. The engineering menu has "WiFi" and "Bluetooth" items that allow you to start scanning the available networks. The device must see not only the high-power access points, but also weak signals. The modules must be disabled correctly.

Navigation (GPS/GLONASS/Galileo) is checked through the map app or in the "GPS" section of the test menu. The phone should quickly determine the location (in 5-10 seconds) if you are not in a deep basement.

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Successful 5GHz Wi-Fi connection and a stable Bluetooth signal are markers of serviceability of the antenna module, which is difficult and expensive to repair.

Frequent questions when buying Xiaomi (FAQ)