Fitness bracelet Mi Smart Band 4C Xiaomi is a budget-friendly but functional device for monitoring activity, sleeping and receiving notifications. 9A They have difficulty connecting for the first time: the bracelet is not detected by the phone, the Mi Fitness app emits errors, and the sync is interrupted, often because of the smartphone's firmware, Bluetooth versions, or energy saving settings.
In this article you will find the current instructions for 2026, taking into account all the nuances of the Mi Band. 4C redmi 9A (We will not only analyze the basic pairing, but also hidden settings that will help to avoid disconnection, increase the battery life of the bracelet and customize notifications to your needs.
If you've already tried to connect the bracelet and you've got an error: You couldn't find the device or Synchronization failed, don't rush to reset the settings. In 90% of cases, the problem is solved by adjusting the phone parameters, which the manufacturer does not mention in the official documentation.
1.Redmi phone preparation 9A plug-in
Before pairing with the Mi Smart Band 4C You need to optimize the Redmi settings. 9A, To avoid common errors, pay special attention to the firmware version and Bluetooth status.
Important: Redmi 9A Based on the MediaTek Helio processor G25 It has limitations on Bluetooth 5.0 protocol support. 4C use BLE (Bluetooth Low Energy, but you need to activate additional settings for stable operation.
Follow the following steps:
- 📱 Update your phone firmware to the latest version. For the global version, check Settings → The phone. → System Update: Minimum supported version — MIUI 12.0.8.
- 🔄 Reboot your phone. This will reset the Bluetooth cache and eliminate possible conflicts with other connected devices.
- 🛠️ Turn off the power saving mode for the Mi Fitness application (instructions in the next section).
- 🚫 Delete data from other fitness apps (such as Google Fit or Huawei Health) if it has been installed before.
Critical Feature: Redmi 9A with firmware for the Chinese market (China) ROM) It can block background activity of Mi Fitness. If you have this version, install alternative software (e.g. Xiaomi.eu) before connecting or use the bypass method through Settings. → Special facilities → Notifications → Priority notifications.
2. Installation and configuration of the Mi Fitness application
Official application for managing Mi Smart Band 4C — Mi Fitness (formerly Mi Fit) must be downloaded from Google Play or Mi App Store, but there are nuances:
For Redmi. 9A Mi Fitness 5.12.0 or later is recommended. older versions may not support Mi Band 4C Or work with errors. If the app is not available in your region, download it. APK from a trusted source (such as APKMirror), but disable automatic updates via Settings → Annexes → Mi Fitness → Auto-update.
After installation, perform the initial setting:
- Start Mi Fitness and sign up through your Xiaomi account (or sign in if you already have one).
- Click Profile → Add Device → Bracelet → Mi Smart Band 4C
- Allow all permissions (geolocation, notifications, access to contacts) to be requested.
- Enable Automatic Synchronization in the application settings.
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Note: If you register for a Xiaomi account with a phone number, use the same region as in the phone firmware. ROM Select the country of purchase of the device. The region mismatch may result in blocking some of the bracelet's features.
The latest version of the application has been installed|Xiaomi account registered and confirmed|All permissions for Mi Fitness are included|Background activity of the application is allowed|Other fitness apps disabled-->
3. Step-by-step pairing of the Mi Band 4C redmi 9A
Now, to the connection itself, follow the instructions carefully, the order of action is important.
1. activation of Bluetooth on the phone:
Go to Settings. → Connections → Bluetooth and turn it on. Make sure Visibility mode is activated for 2 minutes).
Preparation of the bracelet:
- Charge the Mi Band. 4C Up to 50% (charging indicator – green LED).
Press the touch button of the bracelet and hold for 5 seconds until the vibration and the Mi logo appear.
3. Search for the device in Mi Fitness:
- In the app, click Add Device → Mi Smart Band 4C.
Wait for the phone to find the bracelet (it can take up to 30 seconds).
On the screen of the bracelet will appear 4-digit code - confirm it in the application.
Completion of the setting:
Choose the main arm (left/right) to wear the bracelet.
Enter personal data (gender, age, weight) to correctly calculate calories.
Allow access to notifications (see the next section).
If the bracelet is not present, try:
- 🔌 Reboot your phone and bracelet.
- 📶 Turn on Flight Mode on the phone for 10 seconds, then turn off.
- 🔄 In Mi Fitness, click Update Device List.
What if the bracelet is connected, but immediately disconnected?
4. Set up notifications and synchronization
Default Mi Band 4C It shows notifications of calls and SMS, But to display messages from messengers (WhatsApp, Telegram, Viber) requires manual configuration.
How to enable notifications from applications:
- In Mi Fitness go to Profile → Mi Smart Band 4C → Notifications of annexes.
- Activate the Display Notifications switch.
- Select the apps you want to see on your bracelet (maximum 10).
- In the Android settings for each messenger, allow to Show notifications and display on a locked screen.
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Attention: On Redmi 9A s MIUI 12 and below notifications may be duplicated or late.To fix this, turn off Floating notifications in Settings → Notifications → Additionally.
Optimization of data synchronization:
| Parameter | Recommended value | Reason. |
|---|---|---|
| Synchronization frequency | Every 30 minutes. | Balance between data relevance and battery consumption |
| Autosynchronization over Wi-Fi | On. | Reduces the load on Bluetooth |
| Background activity of Mi Fitness | No restrictions. | Prevents communication breakage |
| Low charge notifications | 10% | The optimal threshold for timely charging |
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If notifications are not in Russian, check the system language in Mi Fitness. → Settings → The language of the app and select Russian. This will also change the language of the bracelet interface.
5. Solving common problems
Even after the successful connection, Redmi users 9A They can get into mistakes. Here are the most common ones and how to fix them:
Problem 1: The bracelet is connected, but the data is not synchronized
- 📵 Check if the mobile Internet is on or the wifi on your phone.
- 🔄 In Mi Fitness go to Profile → Mi Smart Band 4C → Synchronize data and manually press.
- 🗑️ Clear the app's cache: Settings → Annexes → Mi Fitness → Memory. → Clear the cache.
Problem 2: The bracelet discharges quickly
- 🔋 Turn off the Raising of the Hand to activate the screen in the bracelet settings.
- 📶 Reduce the synchronization frequency to 1 time per hour.
- 🚫 Disable notifications from unnecessary applications.
Problem 3: Notifications are not fully received or cut off
- 📝 In Android settings for each messenger, turn off Notification Compression.
- 🔤 In Mi Fitness, enable the option to Show full notifications.
Problem 4: The bracelet doesn't vibrate when notified
- 🔕 Check if Do Not Disturb on the bracelet is enabled (hold the touch button for 3 seconds to check).
- 🎵 In the phone settings, make sure that the sound profile is not set to No Sound.
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If after all the manipulations the bracelet continues to turn off, try to reset it to the factory settings. → Mi Smart Band 4C → Untie the device, then repeat the connection process again.
6. Additional functions and hidden capabilities
Mi Smart Band 4C It supports features that many users don’t know about, and here are the most useful ones for Redmi owners. 9A:
1.Music control from the bracelet
You can switch tracks and adjust volume directly from the Mi Band. 4C, If you pre-enable this option:
- 🎵 In Mi Fitness, go to Music Management → Turn on.
- 📱 On the phone in Bluetooth settings for Mi Band 4C Permission to the Media Authority.
2. Phone search
If you lost Redmi 9A, You can make him ring from the bracelet:
- On the bracelet, swipe up the screen.
- Select the phone search icon (phone icon with waves).
- The phone will give a loud signal, even if it is silent.
Setting alarm clocks
Mi Band 4C It supports up to 10 alarm clocks that will vibrate even if the phone is turned off:
- ⏰ In Mi Fitness, go to the Alarms → Add an alarm clock.
- 🔄 Set Repetitive Days and Vibration Strength (3 Levels).
- 🛌 For a “smart” awakening, turn on the Light Sleep Phase – the bracelet will wake you up at the optimal time 30 minutes before the alarm clock.
4. Sleep monitoring with detailed analytics
The bracelet automatically tracks sleep phases, but for accurate data:
- 😴 Wear the bracelet on the non-dominant hand (for right-handed - left, for left-handed - right-handed).
- 📊 In Mi Fitness, enable Sleep Analysis → Detailed report.
- ☕ Calibrate the bracelet: lie still for 5 minutes before going to bed so that the sensors adapt.
How to turn on the weather display on the bracelet?
7. Optimization of the autonomy of the bracelet
Standard operating hours of the Mi Band 4C — Up to 14 days, but in practice with Redmi 9A This is often reduced to 7-10 days. Here's how to prolong autonomy:
Bracelet settings:
- 🌙 Setting a sleep mode for the period from 23:00 to 7:00 – this will turn off unnecessary functions at night.
- 🔦 Turn off the light when lifting your arm or reduce its duration to 3 seconds.
- 📶 Reduce the automatic synchronization frequency to 1 time in 2 hours.
Phone settings:
- 🔋 B Settings → Battery → Battery mode select Balanced (not Performance).
- 📴 Turn off Permanent search for Bluetooth devices in Settings → Connections → Bluetooth → Additionally.
- 🔄 In Mi Fitness, disable Auto-Update of the bracelet firmware – this will prevent unexpected discharges during updates.
Battery consumption table depending on functions:
| Function | Daily expenditure | Recommendation |
|---|---|---|
| Constant pulse. | 15–20% | Only turn on during training |
| Notifications (10)+ day-to-day) | 8–12% | Limit to 5 important applications |
| Lighting up when lifting your hand | 5–10% | Turn off or reduce the brightness |
| Sleep tracking | 3–5% | Leave it on. |
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If the bracelet is dead, plug it into charging and wait 5-10 minutes before turning on. Pressing the button too early can reset the firmware and you will need to reconnect.