How to Reset Xiaomi Humidity Sensor: 5 Verified Ways (2026)

Xiaomi’s humidity sensors are some of the most popular devices in the smart home ecosystem. They are compact, accurate (under ideal conditions) and easily integrated with the Mi Home, Home Assistant or Aqara Hub. But even the most reliable technology sometimes fails: humidity readings “hang” by 99%, display absurd 0%, or values jump from 20% to 80% in a few minutes. 80% of the problem is solved by a software reset of the sensor – and this is what our article is about.

We analyzed user reports from 2023 to 2026, official Xiaomi recommendations (including internal documents for service centers) and tests by independent laboratories to collect current dumping methods. Not all methods are universal — the effectiveness depends on the sensor model, firmware version and the cause of the failure. for example, for Xiaomi MiJia Bluetooth Temperature and Humidity Sensor 2 (LYWSD03MMC) One algorithm is suitable for Aqara. TVOC Air Quality Monitor is different. To avoid wasting time, start with the Diagnostics of a Problem section to determine if a reset is needed at all.

If you've tried rebooting the sensor through an app before and it didn't work, don't rush to throw it away. 60 percent of the time, hardware resets (as discussed in Section 3) help, and 25 percent of the time, flashing through alternative tools like this. ATC MiThermometer or Custom Firmware for Xiaomi Devices.

1. Diagnosis: When is a reset really needed?

Before you drop the sensor, make sure that the problem is not external factors.Here are 3 key signs that the device requires resetting:

• 📉 Indications “frozen” on one value (for example, 99% humidity in a dry room) for more than 12 hours.
• 🔄 Rises in values without changes in the environment (from 30% to 70% in 5 minutes).
• ❌ Mi Home Communication Error: Sensor shows up as 'offline' even though battery charged.

If any of the items match, move on to reset, but first check for alternative causes:

Critical error: if the sensor shows humidity above 100% or temperature below -50°Indoor C is a sure sign of hardware failure. Reset won't help, you'll need to replace the sensor or the entire device.

⚠️ Warning: Don't confuse sensor reset with data history zeroing in Mi Home.The story is erased in the app settings and the reset affects the device itself.The history zeroing doesn't affect current readings!

Method 2: Software reset via Mi Home (for most models)

The most secure method, which works for 70% of Xiaomi and Aqara devices, is suitable for sensors connected to Mi Home or Aqara Home via a gateway, and the instructions are relevant for the 6.0.100 and later versions of the application (2026).

Algorithm of action:

1. Open Mi Home and go to the Devices tab.
2. Find your humidity sensor and tap it.
3. In the upper right corner, press on ⋮ → Settings of the device.
4. Scroll down and select Reset (or Remove Device if there is no Reset option).
5. Confirm action. The sensor will flash red/blue light, signaling a successful reset.

After discharge:

• 🔄 The sensor will automatically restart (take 1-2 minutes).
• 📱 You will have to re-add it to Mi Home via Add the device. → Sensors.
• ⚡ If the sensor does not appear in the list, remove and insert the battery again.

Features for different models:

• 📌 LYWSD03MMC: After the reset, you may need to update the firmware through ATC MiThermometer.
• 📌 Aqara WSDCGQ11LM: Reset is available only through Aqara Home, Mi Home may not be available.
• 📌 Yeelight YLYK01YL: Reset causes calibration data loss – reconfiguration will be required.

⚠️ Note: If the sensor is connected via Home Assistant or Zigbee2MQTT, A software reset via Mi Home can cause you to lose your connection to the Zigbee network, in which case you first remove the device from Home Assistant, then reset it.

Make sure the battery is charged (replace in case of doubt)

Close all background applications on a smartphone

Stay in the zone. Wi-Fi/Bluetooth

Prepare tweezers to remove the battery (in case of error)

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Method 2: Hardware reset (button or battery)

If the software reset didn’t help or the sensor doesn’t show up in the Mi Home, try a physical reset.This method works for 90% of Xiaomi devices, but requires care – wrong actions can damage contacts.

Option A: Reset button (if any)

Some models (e.g. Aqara) TVOC Air Quality Monitor has a hidden reset button to find it:

1. Turn over the sensor and inspect the case for a small hole with the inscription RESET.
2. Take a paper clip or toothpick, press and hold the button for 5-10 seconds.
3. The sensor should flash 3 times red - this is a signal of a successful reset.

Option B: Battery discharge (universal method)

Suitable for all Xiaomi sensors without a physical reset button:

1. Remove the battery (use a plastic card or tweezers to avoid damaging the contacts).
2. Wait at least 30 seconds – that’s enough time for the capacitors to run out.
3. Insert the battery back, observing polarity (+ upward).
4. The sensor should flash blue, which means it is ready to be re-tuned.

What to do if the sensor does not respond?

• 🔋 Check the battery: even the "fresh" can be discharged. Try another one (for example, Duracell). CR2032).
• 🧲 If the sensor is magnetic (for example, Xiaomi MiJia) LYWSD02), Apply a magnet to the back cover for 2 seconds – this sometimes works as an alternative reset.
• 🌡️ Place the sensor in a dry place for 12 hours - sometimes condensate on the board blocks work.

Method 3: Reset via alternative firmware (for advanced)

If standard methods have failed and the sensor supports custom firmware (e.g, LYWSD03MMC or CGDK2), You can try to reflash it. It's a last resort, but it restores performance in 95 percent of cases.

Tools required:

• 📱 Smartphone on Android (for Android) ATC MiThermometer or Python PC (for telink-flasher).
• 🔌 Cable USB-TTL (for example, CP2102) sensor-wire.
• 💾 Firmware: official (from Xiaomi website) or custom (for example, OpenMQTTGateway).

Step-by-step instructions for LYWSD03MMC:

1. Download. ATC MiThermometer from GitHub.
2. Connect the sensor to the phone via Bluetooth.
3. In the app, select Firmware Update → Custom Firmware.
4. Download the firmware file (for example, lywsd03mmc_v2.1.1.bin).
5. Start the firmware and wait for completion (it will take 2-5 minutes).

Warnings:

• ⚠️ Continuous power: if the battery sits down during firmware, the sensor will turn into a “brick».
• ⚠️ Compatibility: Firmware from LYWSD03MMC not fit for CGDK2 — check the model!
• ⚠️ Guarantee: custom firmware removes the warranty (if it is still valid).

Important: Once the sensor is firmware, it may lose communication with the Mi Home, in which case it will have to be connected via alternative systems (Home Assistant, Zigbee2MQTT).

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Before you run the firmware, back up the sensor data via Mi Home (if it still works). To do this, export your reading history to Excel via Settings. → Export of data.

5. Method 4: Calibration of the sensor (if the reset did not help)

Sometimes the problem is not the failure, but the calibration of the sensor, which is typical for sensors older than 2 years, their accuracy drops by 5-15%, calibration will help to return the correct readings without completely resetting.

Method 1: Salt calibration (for hygrometers)

1. Place the sensor in a sealed bag with edible salt (not iodized!).
2. Add a few drops of water to make the salt wet but not wet.
3. Close the bag and leave it for 8-12 hours, and the humidity inside stabilizes by 75%.
4. If the sensor shows a value other than 75% ±3%, calibration is required through software.

Method 2: Programmatic calibration (for supported models)

Some sensors (e.g. Aqara) WSDCGQ11LM) allow manual adjustment of readings:

1. In Mi Home, go to the sensor settings.
2. Select Calibration. → Humidity.
3. Enter the correction factor (e.g, +5% if the sensor is underestimating).
4. Save the settings and check the readings after 1 hour.

Table of accuracy after calibration:

⚠️ Note: Salt calibration is not suitable for sensors with capacitive sensors (e.g. Xiaomi) CGDK2). Use only software methods or special calibration cameras for them.

Method 5: Reset via Zigbee commands (for sensors with a hub)

If your sensor is connected to the Xiaomi Gateway or Aqara Hub using the Zigbee protocol, it can be reset via console commands. MQTT or Zigbee2MQTT.

Instructions for Zigbee2MQTT:

1. Open the web interface Zigbee2MQTT (usually http://[IP_hub]:8080).
2. Find your sensor in the list of devices and copy it friendly_name.
3. Send the reset team through MQTT: mosquitto_pub -h [IP_broker] -t "zigbee2mqtt/[friendly_name]/set" -m '{"reset": true}'
4. Wait for the answer {"reset": "ok"}.

For Xiaomi Gateway (via Mi Home Automations):

1. Create a new automation in Mi Home.
2. Select the Device as the trigger → [Your sensor] → Any event.
3. In action add Send a command. → Reset.
4. Save and run the automation manually.

Frequent errors:

• 🚫 Commands don't work if the sensor isn't on the network (check the link to the hub).
• 🚫 For some models (e.g, WSDCGQ01LM) A specific team is required: {"reset_humidity": true}.
• 🚫 After reset, the sensor can change the address in the Zigbee network – you will need to re-assign.

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Resetting via Zigbee commands is the most reliable way for sensors integrated into a smart home, requiring no physical access to the device and storing network settings.

7. What should I do if nothing has worked?

If none of these methods worked, it could be a hardware malfunction.

• 🔍 Contact oxidation: disassemble the sensor (carefully!) and check the corrosion board.
• 📡 Interference from other devices: Xiaomi sensors operate at 2.4 GHz – the same channels use Wi-Fi routers and microwaves.
• 🌡️ Sensor failure: If the sensor fell or was exposed to extreme temperatures, the sensor could be damaged.

When to contact the service:

• 🛠️ The sensor does not respond to any manipulations (does not blink, does not detect).
• 💧 Humidity readings are overstated by 20%+ even after calibration.
• 🔥 On the board you can see blackened elements or the smell of burning.

Cost of repairs in official Xiaomi service centers (2026):

Alternative to repair: If the sensor is older than 3 years, it is sometimes cheaper to buy a new one. LYWSD03MMC worth ~1 500 ₽, aqara WSDCGQ11LM — ~2 000 ₽ (June 2026).

FAQ: Frequent questions about resetting Xiaomi sensors