How to connect Xiaomi temperature and humidity sensor to Alice: 3 working ways (2026)

Why Alice Can't See Xiaomi Sensor and How to Fix It

You bought a temperature and humidity sensor Xiaomi (models) LYWSD03MMC, LYWSD02 or MHO-C401), But Alice refuses to see it? It's not the device that's the problem -- 90 percent of the cases are due to misintegration between the Mi Home and Yandex Smart Home ecosystems. In this article, we'll look at three proven ways to connect, including workarounds for devices without official support.

The main problem is that Xiaomi and Yandex use different data exchange protocols, and even if the sensor is successfully added to the Mi Home, Alice will not see it without additional manipulations. We tested all the current methods on firmware from 2023-2026 and identified those that work stably (including solutions for sensors with custom firmware).

Method 1: Official connection via Mi Home + Yandex Smart Home

This is the easiest method, but it only works for Yandex-enabled sensors (see the list of compatible models below). If your device is on this list, you're lucky: integration will take no more than 5 minutes.

Algorithm of action:

• 📱 Install the Mi Home app (version no lower than 6.5.400) and log in.
• 🔗 Add a sensor to Mi Home via Devices → Add the device → Sensors. → Temperature/humidity.
• 🏠 Go to Profile. → Settings → Smart home. → Yandex and Link Accounts.
• 🗣️ Open the Yandex app, go to the Smart Home → Devices → Add → Xiaomi.

Make sure the sensor is charged (battery) CR2032)

Update Mi Home to the latest version

Connect your phone to a 2.4 GHz network (sensors don’t work with 5 GHz)

Turn it off. VPN/proxy in the phone settings-->

⚠️ Note: If the sensor does not appear in Yandex Smart Home after the account bundle, check the region in Mi Home. It must be Russia (not China or Europe). You can change the region in the profile settings, but this will result in the reset of all devices!

Method 2: Connecting through third-party services (Home Assistant, IoBroker)

If your sensor isn't officially supported, you'll have to use an intermediate server, and the most reliable options are Home Assistant or IoBroker, which act as a bridge between Mi Home and Yandex Alice, transferring data from one protocol to another.

For Home Assistant, the instructions are as follows:

1. Install Home Assistant on the Raspberry Pi, NAS, or Virtual Machine.
2. Add Xiaomi Mi integration through Settings → Devices and services → Add integration.
3. Enter the username/password from Mi Home (required to enable) API China in account settings).
4. Install the Yandex Smart Home expansion through HACS.
5. Link accounts in the add-on settings.

⚠️ Warning: When setting up Home Assistant, disable two-factor authentication in Mi Home – it blocks access to the Home. API. Also make sure that yours is yours. IP Xiaomi is not blocked (Chinese servers are often banned from Russian) IP).

The algorithm is similar for IoBroker, but you will need to:

• 🖥️ Install adapter-mi-home and adapter-yandex-smart-home.
• 🔑 Get Token from Mi Home via mihome.dev.
• 🔄 Set up entity synchronization between adapters.

Home Assistant|IoBroker|Yandex Smart Home|Other|I don't use it.-->

Method 3: Flashing the sensor to alternative firmware (ATC, PVVX)

If the first two methods did not work, the last measure remains - reflash the sensor on custom firmware with support MQTT or HTTP API. This will allow you to transfer data directly to Yandex Smart Home via Yandex IoT.

The most popular firmware for LYWSD03MMC and LYWSD02:

• 📦 ATC MiThermometer supports MQTT, Home Assistant, InfluxDB.
• 📦 PVVX Custom Firmware adds HTTP API and compatibility with Tasmota.
• 📦 OpenMQTTGateway – universal firmware for devices on ESP8266.

Flashing process:

1. Download the firmware from GitHub (for LYWSD03MMC Choose a version BLE).
2. Unpack the sensor (neatly lid with a knife or mediator).
3. Connect the contacts. GND, TX, RX ce USB-TTL adapter (voltage) 3.3V!).
4. Run the firmware through esptool: esptool.py --port COM3 write_flash 0x0 firmware.bin
5. Set up. MQTT in the sensor web interface (opens on 192.168.4.1 after firmware).

⚠️ Note: Flashing will void warranty and can cause the sensor to fail if you fail. If you've never worked with esptool, you better consult a specialist. Also note that once you've firmware, the sensor will stop working in Mi Home - only through the help of a new device. MQTT.

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Before the firmware, take a picture of the location of the contacts on the sensor board. This will help avoid short circuits when connecting. USB-TTL adapter.

Addressing common mistakes

Even if you connect it properly, it might not be showing up in Alice or giving out incorrect data.-5 problems and solutions:

1. Alice says "The device is unresponsive"

Reasons:

• 🔋 The battery sat down (even if the sensor flashes, the voltage could subside).
• 📶 Weak signal. Bluetooth/Wi-Fi (sensor should not be further away 10 m from the lock).
• ⚙️ Synchronization failure between Mi Home and Yandex.

Solution: Reboot the Xiaomi gateway (if used), check the battery with a multimeter (should be) ≥2.8V), Reconnect the sensor to Mi Home.

Data are updated once an hour (instead of 5 minutes)

This is Xiaomi's limit to save battery life. To change the interval:

• In Mi Home, go to the sensor settings → Update mode → Choose Often.
• For the stitched sensors, change the parameter update_interval configurably MQTT.

3 Alice shows temperature with error +5°C

Typical sensor problem LYWSD03MMC Firmware 2020-2022 Solutions:

• Update the firmware through Mi Home (if the sensor is original).
• Add the correction to Home Assistant: template: - sensor: name: "Temperature Corrected" unit_of_measurement: "°C" state: "{{ states('sensor.lywsd03mmc_temperature')|float - 5 }}"

4.The sensor disappeared from the Yandex Smart Home after the update

This is because the access token is reset, to restore:

1. Untie your Xiaomi account in the Yandex Smart Home settings.
2. Remove the sensor from the Mi Home and add it again.
3. Repeat the account linking procedure.

5. "Device not supported" error

If your sensor model is not on the compatible list (see table above), use:

• 🔄 The bypass through Home Assistant (Method 2).
• 🔧 Flip-on ATC/PVVX (Method 3).
• 🛠️ Emulation of supported device through MQTT (requires programming skills).

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If the sensor is not officially supported, the only working options are Home. Assistant/IoBroker Official support from Yandex is unlikely for older models.

How to set up voice commands for the sensor

Once the connection is successful, you have to configure voice control, and Alice understands the following types of queries:

To create automation (e.g., turn on the heater when the temperature drops):

1. Open Yandex Smart Home → Scenarios → Create a script.
2. Select the condition: Temperature [sensor name] < 20°C.
3. Add the action: Turn on [heater].
4. Save the script and activate it with the voice: "Alice, start the heat."

⚠️ Attention: The scenarios only work if the sensor is online. If the connection to the sensor is interrupted (for example, the battery is dead), the automation will stop working.

Comparison of Connection Methods: What to Choose?

What's the best way to do this? Let's compare them by key parameters.

Selection recommendations:

• 🏆 For beginners: Official method (if the model is supported).
• 🛠️ For advanced users: Home Assistant + MQTT.
• 🔧 For enthusiasts: Refashioning on ATC/PVVX (If you need maximum flexibility).

FAQ: Frequent questions about connecting Xiaomi sensor to Alice