Xiaomi thermometers are some of the most popular smart gadgets for health, but their compact body often raises questions from users: Do you want to replace the battery, clean the sensor or just figure out what is inside? In this article, we will discuss in detail how to open the thermometer Xiaomi different models – from the classic Mi Thermometer to the built-in sensors in fitness bracelets Mi Band.
It's important to understand that Xiaomi thermometers are different from traditional mercury or electronic thermometers. There are no screws or obvious latches, the case is glued or soldered to protect against moisture (IP67/IP68 standard). Incorrect opening can lead to damage to the sensor, loss of leakage or even loss of warranty if the device is still in service. We will tell you what tools you need, how to avoid typical errors and what to do if the the the the thermometer stopped working after dismantling.
What Xiaomi Thermometers Can Be Opened By Yourself
Not all Xiaomi thermometers are disassemblable at home, and here is a list of models that can be used without specialized equipment:
- 🔹 Xiaomi Mi Thermometer (classic version with Bluetooth, article MJT01ZM)
- 🔹 Xiaomi Mi Thermometer 2 (updated version with improved sensor)
- 🔹 Xiaomi Mi Band 4/5/6/7 (inline skin temperature sensor)
- 🔹 Xiaomi Mi Bunny Thermometer (children's version with cute design)
- 🔹 Xiaomi Smart Thermometer S1 (contactless infrared)
But these models are not recommended to be analyzed:
- ❌ Xiaomi Mi Thermometer E1 — the case is soldered with ultrasound, high risk of damage.
- ❌ Xiaomi Mi Temperature and Humidity Sensor 2 is a humidity and temperature sensor in one case, sensitive to mechanical stress.
- ❌ Any thermometer marked IP68 (full dust-water protection) - after opening loses its leakage.
If your model is not on the first list, it is better to contact the service center. For example, the contactless Xiaomi Smart Thermometer S1 has a lens made of special glass that is easy to scratch when you open it sloppy.
Preparation for disassembly: tools and security measures
Before you start, prepare everything you need. Without the right tools, you risk damaging the board or disrupting the battery contacts.
| Tool. | What do you need? | The alternative |
|---|---|---|
| Plastic mediator (1-2 units) | Separation of the shell without scratches | Guitar Mediator or Credit Card |
| Thin screwdriver (cross, 1.5 mm) | Removing hidden screws (if any) | Watch repair screwdriver |
| Tweezers with curved ends | Extraction of plumes and small parts | Manicure tweezers |
| Hair dryer (60-80°C) | Softening of glue (for models with glued body) | Water bottle or hot water (caution!) |
| Isopropyl alcohol (90%+) | Cleaning contacts and removing glue residues | Purified gasoline (kalosha) |
You'll also need an antistatic mat or at least a grounded table -- static electricity can damage sensitive sensors. If you're disassembling the Mi Band, prepare a special key to remove the strap (which comes with it) -- without it, you can damage the latches.
⚠️ Warning: Don't use metal objects (knives, scissors) to open the case! They leave scratches and can close contacts on the board. If the thermometer is warranty, disassembly will void it - Xiaomi puts seals on the screws.
Step-by-step: how to open Xiaomi Mi Thermometer (classic model)
Consider the most common model, the Xiaomi Mi Thermometer (MJT01ZM), which is glued together, but can be disassembled without damage with careful approach.
Take a picture of the body from all sides (useful for assembly)|
Turn off the thermometer from the Mi Home| app
Place it on a soft surface (towel)|
Prepare a container for small parts-->
- Warm up the body. Turn the dryer on at a minimum temperature (60-70°C) and warm the body seam around the perimeter for 2-3 minutes. This will soften the glue. Alternatively, put the thermometer in warm water (not boiling water!) for 5 minutes.
- Separate the halves. Insert the plastic mediator into the seam between the top and bottom of the case (start on the side where there is no display). Carefully lead the mediator around, scrolling it slightly to separate the halves.
- Removal of the board. Once the case opens, you'll see a board with a CR2032 battery, and you'll be careful to tweez it, and it can be pasted with double-sided tape.
- Disconnect the display plume. If your model is screened, find the white plume connector (usually fixed by a latch). Pull the latch up with tweezers and carefully pull the plume out.
Inside you'll see:
- 🔋 Battery CR2032 (3 Volts).
- 📱 Board with Bluetooth module Nordic nRF52832.
- 🌡️ Texas Instruments temperature sensor TMP117 (accurate to ±0.1°C).
- 📶 Antenna (thin copper track on board).
What if the body does not yield?
Features of disassembling the thermometer in Mi Band 4/5/6/7
If you need to get to the temperature sensor in the Xiaomi Mi Band fitness bracelet, the process will be more complicated. Here, the body is not only glued, but also has latches that are easy to break.
Here are the key differences from the classic thermometer:
- 🔧 You need to remove the strap first with a special key (included). Without it, you'll damage the latches!
- 🔥 The dryer should be spot warm – only heat on the edges of the case so as not to damage the OLED- screen.
- 📱 Inside, you'll find not a removable battery, but a lithium polymer battery soldered to a board. It's dangerous to unplug it without a soldering iron!
- 🌡️ The temperature sensor in the Mi Band is the STMicroelectronics STS30 chip, and it's very fragile.
Disassembly algorithm:
- Take off the strap with the key.
- Place the bracelet with the screen down on a soft surface.
- Warm up the upper part of the body (where the Mi logo) for 1-2 minutes.
- Insert the mediator in the seam next to the button and gently separate the halves.
- Disconnect the screen plume (latch at the top).
⚠️ Warning: The Mi Band 6/7 uses adhesives with conductive particles to protect against moisture. Once disassembled, the seal will be broken and the bracelet will lose water resistance! If you only need a temperature sensor, consider buying an external Xiaomi thermometer.
💡
If you just need to reset your thermometer settings (for example, after a synchronization failure), don't disassemble it! In most models, it's enough to hold the power button 10-15 seconds before vibration or reset via the Mi Home app (Device → Settings → Reset section).
Frequent Mistakes and How to Avoid Them
Even with careful disassembly, users often make mistakes that disable the thermometer.
| Mistake. | Effects of consequences | How to avoid |
|---|---|---|
| Use of metal tools | Scratches on the body, closing contacts | Just plastic mediators! |
| Hair dryer warm-up above 80°C | Melting plastic, detachment of plumes | Control the temperature with a thermometer |
| Sharp separation of halves of the body | Breakage of the display or sensor plume | Move the mediator slowly, without jerking. |
| Touching the board with bare hands | Static electricity damages chips | Use an antistatic bracelet or gloves |
| Replacing the battery with an unoriginal battery | Electrolyte leakage, contact corrosion | Buy CR2032 from proven brands (Panasonic, Duracell) |
Another common problem is the loss of sync with the application after disassembly, which happens if you forget to lock the Bluetooth antenna or damage its contacts during assembly.
- 📱 Before disassembling, untie the thermometer from your Mi Home account.
- 🔧 After assembly, reset settings (hold the 10 seconds button).
- 🔄 Connect the device again through the app.
1. battery polarity (plus should be on top!).
2. Contacts of the display plume (they may not fully stand in the connector).
3. Bluetooth antenna integrity (thin copper track on board).-->
What to do after a successful disassembly
You opened the thermometer -- what's next? Here are the most common problems and solutions.
- 🔋 Battery replacement: Mi Thermometer models use the CR2032 element. Buy a new battery (preferably with a manufacturing date no older than 1 year) and set it upside down. Once replaced, the device will automatically turn on.
- 🧹 Contact cleaning: If the thermometer is glitching or not synchronized, wipe the battery and board contacts with a cotton swab soaked in isopropyl alcohol. Don't use water!
- 🛠️ Sensor repair: If the temperature sensor shows wrong values, check its contacts on the board. Re- soldering sometimes helps (but it requires skill).
- 💧 Retightening: Once assembled, apply a thin layer of silicone sealant (e.g., Dow Corning 7091) to the body seam, which will partially restore moisture protection.
If you've been disassembling the Mi Band and you need to replace the temperature sensor, you don't sell it separately. You'll have to buy a donor fee on AliExpress or at service centers, and the cost of repairing it is often the same as the price of a new bracelet.
When the Disassembly is Inappropriate: Alternative Solutions
Sometimes opening a Xiaomi thermometer is pointless, and here are some of the best times to consider other options:
- 🚫 Thermometer warranty, disassembly will void it, repairs at the service center can be free.
- 🚫 Synchronization problems, most often solved by reconnecting to Mi Home or resetting.
- 🚫 Mechanical damage to the body. If the screen cracks or the body bends, self-repair usually doesn't help.
- 🚫 Moisture intake, which requires professional cleaning and drying in an ultrasonic bath.
Alternative solutions:
- 🔄 Reset via app: Go to Mi Home → Device → Settings → Reset.
- 📞 Support: Write to the Xiaomi chat (the “Feedback” section in the app) describing the problem.
- 🛒 Buying a new thermometer: Prices for Xiaomi Mi Thermometer start at 800 rubles, and repairs can cost more.
⚠️ Warning: If your Xiaomi thermometer stopped turning on after a fall or impact, most likely the board is damaged or the battery contacts are soldered off. In this case, disassembly without a soldering iron and multimeter is meaningless - contact the service.