How to check the fitness bracelet Xiaomi Mi Band: from battery to sensors

Why it’s important to check your fitness bracelet before buying or after repairs

The Xiaomi Mi Band fitness bracelets are some of the most popular wearables on the market, thanks to their price-to-function ratio. However, even new models out of the box can have hidden defects, from heart rate sensor malfunction to Bluetooth synchronization problems, and if you buy a used bracelet or just got one after repair, the risk of running into a malfunction increases significantly.

In this article, we will discuss all ways to check the Mi Band (including the Mi Band models). 6/7/8, Smart Band 7 Pro and more, from basic tests to hidden malfunctions, you'll learn how to test the battery, touch screen, pulsemeter, pedometer, and even waterproof without special equipment. Special attention will be paid to checking the originality of the bracelet - fake Xiaomi often disguised as the originals, but give themselves away for trifles.

If you are planning to buy a wristband or have already encountered suspicious device behavior (e.g., fast battery setting or incorrectly counting steps), this guide will help you identify problems in 10-15 minutes.

1. External inspection: how to distinguish the original from a fake

The first stage of the inspection is visual. Fake Xiaomi Mi Band often copy the design, but miss the details.

• 📦 Packaging: Xiaomi's original box features matte coating, a clear logo print and a hologram on a sticker.Fakes often use glossy cardboard and blurry fonts.
• 🔍 Build quality: the original bracelet has no gaps between the body and the strap, the button (if any) is pressed with a slight click.
• 📱 QR-code: on the back of the original Mi Band body is marked QR-A code that leads to Xiaomi's official website, and fakes may use fake codes or not have them at all.
• 🔋 Charging cable: original bracelets have golden charging contacts and are tightly attached to the body. For fakes, the contacts are often dull or oxide-filmed.

Pay special attention to the serial number (printed on the box and under the bracelet lid), it can be checked on the official Xiaomi website in the support section, if the number does not pass verification, you have 100% fake.

⚠️ Warning: Counterfeiters often mimic serial numbers but give themselves away for trifles, such as sensors that are not working properly or that official firmware is not supported. If the bracelet is too cheap (30-50% below the market), this is a reason to doubt its originality.

2. Battery and Charging Check: How to Find Out Real Capacity

One of the most common defects of used wristbands is a worn-out battery, and even if the seller claims that the battery is "like new," its capacity may have decreased by 30 to 50 percent after a year of use.

1. Charge the bracelet to 100% and disconnect from the power. Use the original cable - fakes can show false charge levels.
2. Reset statistics in the Mi Fit or Zepp Life app (Device section» → «Data resetting»).
3. Activate constant heart rate monitoring and turn on notifications (this will load the battery as much as possible).
4. The original Mi Band 7 should last at least 5-7 days in this mode. If the bracelet goes down in 1-2 days, the battery is worn out.

For more accurate diagnosis, use apps like AccuBattery (if the bracelet supports third-party utilities) or check the charging cycles in the service menu.

1. Go to Bracelet Settings → About the device.


2. Slap 5 times on the line with the firmware version.




3. From the menu that opens, select Battery Info (if available).

⚠️ Warning: If the bracelet is heated during charging or discharged in a few hours without use, this is a sign of a faulty power controller.

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To extend the life of the battery, avoid full discharge and charging to 100%. The optimal range is 20-80%.

3. Touch screen and button testing

A faulty screen is one of the most common problems with used wristbands.

• 👆 Swipe sensitivity: swipe up/down, left/right on the screen. Delays or missed commands indicate touchpad problems.
• 🔘 Press response: tap all the icons on the menu, and if some of the elements don't respond, the sensor layer may have been damaged.
• 🌈 Colors and backlights: turn on maximum brightness. On the original bracelet, the screen is evenly lit, without dark spots or stains. Counterfeits often have dim backlights.
• 💧 Waterproof: If the bracelet supports swimming (for example, Mi Band 7 Pro), check the tightness. It is enough to hold it under a weak stream of water for 1-2 minutes.

For models with a physical button (such as Mi Band 4), check its responsiveness: pressing should be accompanied by a tactile click. If the button "fails" or requires effort, the mechanism is worn out.

Sensor diagnostics: pulsemeter, pedometer, SpO₂

Sensors are the heart of a fitness bracelet, and their malfunction negates all the functions of the device.

1. Put the bracelet on your wrist (2-3 fingers above the bone) and tighten the strap.
2. Start your pulse measurement manually (in the bracelet menu or through the app).
3. Compare the readings with data from another device (for example, a smartphone with a pulseometer or a tonometer — ±5 beats per minute.

If the bracelet shows constantly overestimated (for example, 120 beats / min at rest) or underestimated (40-50 beats / min), the sensor is defective, a common cause is contamination of the sensors or mechanical damage.

To check the pedometer:

1. Reset the step counter in the app.
2. Take exactly 100 steps (you can measure on a flat surface).
3. Compare the bracelet to the actual number. The margin of error is ±5%.

If the bracelet is not counting steps (shows 60-70 instead of 100), check the sensitivity settings in Mi Fit. If it is overestimating (150).+ Steps: Problem in a gyroscope or accelerometer.

For sensor-based models SpO₂ (oxygenation):

• Start the measurement manually (usually available in the bracelet menu).
• Normal values for a healthy person are 95-100%.
• If the bracelet shows 0% or error, the sensor is not working.

5. Checking phone sync and notifications

Without a stable connection to the phone, the fitness bracelet loses half of its functions. Here's how to check the Bluetooth connection and notifications:

1. Connect the bracelet to your phone via the official app (Mi Fit or Zepp Life), and if the device is not located, check if Bluetooth is enabled and if it is blocked by antivirus.
2. Update the firmware (section "Device Profile» → «Software updates. Outdated firmware can cause synchronization failures.
3. Test notifications: Send out SMS or call your phone from another device, check if the notification is displayed on the bracelet (vibration) + If notifications do not arrive, check the settings in the application (Profile) → Notifications).

Test the challenge.

If the bracelet is constantly disconnected from the phone, try:

• 📱 Reconnect it in the appendix.
• 🔄 Reboot your phone and bracelet.
• 🚫 Remove other wearables from the list of conjugates (they can create conflicts).

⚠️ Note: If the bracelet connects to the phone but does not sync the data (steps, sleep, pulse), the problem may be in the region of the Xiaomi account. For example, Chinese versions of the bracelets sometimes do not work with European servers.

6. Testing of additional functions: GPS, NFC, sport-regime

Xiaomi’s advanced models (such as the Smart Band 7 Pro or Mi Band 8 Pro) are equipped with the latest models. GPS, NFC And then there's the extended sports modes:

📍 GPS

Turn on Outdoor Run or Walking and go outside. In 1-2 minutes, the bracelet should "catch" satellites and display the route on the map in the application.

• 🚫 GPS No signal for more than 5 minutes, the antenna is faulty.
• 📍 The route is displayed with a strong error (for example, you walked in a straight line, and on the map zigzag) – a weak signal or software failure.

💳 NFC

To check for contactless payments (available in Mi Band 7 Pro and later):

1. Link your bank card to the Mi Pay or Zepp Life app.
2. Bring the bracelet to the payment terminal (at a distance of 1-2 cm).
3. If the payment does not pass, check if your bank supports Mi Pay and update the bracelet firmware.

🏃 Sport regimes

Run any mode (such as a Treadmill or a Bicycle) and compare it to another device (smartphone or sports watch).

• 📊 Accuracy of distance (for running/walking).
• ⏱️ Timer Correctness (should not be reset or "freeze»).
• 🔥 Calorie measurement (accuracy should not exceed 20%).

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If GPS or NFC They don't work, but the bracelet is new -- check if your model supports these features. For example, the Mi Band 6 doesn't have a built-in bracelet. GPS, NFC It's only in the Pro versions.

Verification of watertightness and leakproofness

Most Xiaomi Mi Band models have 5 standard protection ATM (But over time, the sealing gums wear out and the bracelet can lose its leakiness. Here's how to test this without risking sinking the device:

1. Visual inspection: Check if there are cracks or chips on the body, especially around the buttons and charging connector.
2. Condensate test: Blow on the bracelet screen (like glasses), if there is condensation inside the case, the leakage is broken.

Immersion in water (only for models with 5) ATM!)

• Lower the bracelet in a glass of water for 1-2 minutes.
• After extraction, shake off the water and check if the drops appear under the screen.

If the bracelet is not detected by a computer, the problem may be:

• 🔌 Damaged charging port.
• 🖥️ No driver (install Mi Flash Tool).
• 🛠️ Controller malfunctions USB bracelet.

FAQ: Frequent questions about the Xiaomi Mi Band check