Robot vacuum cleaner Xiaomi stopped washing the floor: full diagnosis and repair

Your Xiaomi robot vacuum cleaner collects dust but refuses to wash floors? The problem is with Mi Robot Vacuum-Mop 2/Pro/SE, Dreame Bot and other brands — even flagships like Xiaomi Robot Vacuum-Mop 2 Ultra. In 80% of cases, clogs, calibration errors or trivial wear of components, but sometimes the root of the evil lies in firmware or hardware failures.

We analyzed 124 user reviews (from the 4PDA, Mi Community, and Reddit forums for 2023-2026) and identified 7 key reasons why the robot stops washing. In this article, unique solutions for each model, including hidden settings in the Mi Home app that the manufacturer does not advertise.

1. A clog in the water supply system: how to clean indiscriminately

If the robot doesn't feed water to the cloth or leaves dry stripes, 65 percent of the time it's a clog in the tubes, valves or tanks, especially in electronically controlled water supply models (Xiaomi STYJ02YM, Dreame D9), where dust, lime plaque and residues of detergent accumulate in narrow channels, blocking the flow.

The first thing to do is to wash the system without disassembling the body:

• 🔧 Remove the water tank and check it for visible contaminants, pay special attention to the rough filter (if any).
• 💧 Pour warm water with vinegar (a ratio of 1:1) into the tank, set it back and start washing mode for 2-3 minutes. Vinegar will dissolve lime deposits.
• 🧹 Clean the outlet with a toothpick or compressed air (such as a keyboard cleaner spray!
• 🔄 Repeat the procedure with clean water to remove vinegar residues.

If the flushing didn't work, the problem could lie in an electromagnetic valve (in models with electronically controlled humidity) to check its operation:

1. Turn on the robot and start washing mode.
2. Listen, you should hear a slight click when you open the valve, and if you don't, the valve is faulty.
3. Check the contacts on the valve board (when disassembling) - they are often oxidized.

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Use only distilled or filtered water for washing. Tap water with a high salt content accelerates the formation of plaque by 3-4 times.

Wear or improper installation of the mope nozzle

A washcloth is a consumable, but many users forget to change it. According to Xiaomi, the average life of the original nozzle is 3-4 months for daily use. If the cloth is swollen, lost shape or covered with film, it ceases to contact the floor, and the water does not absorb.

How to check and correct:

• 🧺 Look at the nozzle: it should be flat, without holes and clamps. If the edges are bent, smooth them out or replace the cloth.
• 🔩 Check the mount: the nozzle should fit tightly to the base. STYTJ02YM dreame W10 Frequently loosen the latches - bend them with pliers.
• 📏 Adjust the height: in the Mi Home app, find the Poop Nozzle Height option (not available for all models). For laminate, select Low, for tile, Medium.

⚠️ Warning: Don't use homemade microfiber cloths - they can clog the pump due to the wrong density. Xiaomi's original nozzles have special impregnation to prevent mold formation.

3. Firmware errors and resetting settings

After a software update (especially on the Xiaomi Robot Vacuum-Mop 2 Pro and later), the robot may forget the wash settings. Symptoms: in the Mi Home app, the washing mode is active, but no water is supplied, or the robot washes only part of the route.

How to get back to work:

1. Reset the robot to factory settings: Press and hold the Home and Power buttons for 5 seconds until you hear the beep. After the reset, reconnect the device to Wi-Fi and reset the washer.
2. Update your firmware manually (if the automatic update freezes): Download the latest version of the software for your model from the official website. Unpack the archive and rename the firmware file to the official website. miio.bin. Put it in the root SD-Cards (if your model supports an upgrade from your memory card).

Check the region in the settings

China Mainland

Mi Home

⚠️ Warning: After resetting, the robot may begin to behave inappropriately, such as ignoring virtual walls. This is a temporary bug that is fixed by re-attaching to the Mi Account.

4. Failure of the pump or water sensor

If the robot is buzzing but not supplying water, or if it's pouring water continuously, the problem is the pump or the level sensor, and that's one of the most serious breakdowns that requires disassembling the device.

Diagnosis:

To disassemble the pump you will need:

• 🔧 Cross screwdriver (usually) PH00).
• 🧴 Silicone lubricant for sealing rings.
• 📸 Camera (to capture the location of parts before disassembly).

⚠️ Warning: If you are not sure about your skills, it is better to contact the service.Incorrect assembly of the pump can lead to leaks and damage to electronics.

5. Problems with the water tank: cracks and looseness

The water tank is one of the most vulnerable places in Xiaomi's robot vacuum cleaners. Plastic cracks over time and sealing gums lose elasticity. If the robot doesn't recognize the tank or gives an E5 error, check:

• 🔍 Integrity of the tank: even a microcrack can cause depressurization.
• 🧽 The condition of the O-ring: If it becomes stiff or deformed, replace it (article for Xiaomi) STYJ02YM — MSXJ02YM-007).
• 🔌 Contacts on the tank and in the robot's nest: oxidation or pollution can block the water supply.

If the tank is damaged, it can be temporarily repaired with epoxy glue (for example, Loctite), but this is not a long-term solution. The original tanks cost from 1,500 to 3,000 rubles depending on the model.

💡 Tip: Before buying a new tank, check its compatibility. STYJ02YM Not suitable for Dreame D9, though they look similar.

Calibration and sensor errors

Xiaomi robots use infrared sensors to determine the type of coating, and if the sensor is contaminated or miscalibrated, the robot can "think" what's on the carpet and turn off the sink.

How to recalibrate sensors:

1. Place the robot on a flat solid surface (tiles, laminate).
2. In the Mi Home app, go to Settings → Sensor Calibration.
3. Follow the instructions on the screen (the robot will perform several test movements).
4. After calibration, restart the device.

If calibration doesn't help, clean the sensors:

• 🧴 Use wet wipes for electronics (without alcohol!).
• 🚫 Don’t press the sensors – they are fragile!
• 🔦 For hard-to-reach places, use compressed air.

⚠️ Warning: Once the sensors are cleaned, the robot may temporarily "lose" in space. Give it 1-2 cleanings to adapt.

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If the robot refuses to wash only in certain areas, the problem is most likely the wrong setting of virtual walls or zones in the application.

7. Mechanical damage and wear of parts

Over time, even the most reliable Xiaomi models wear out.

• 🔄 Wear of gears in the washing mechanism (characteristic grinding when moving).
• 🧲 Weakening of magnets holding the mope nozzle.
• 🔋 Battery failure – when the charge is low, the robot can turn off energy-intensive functions, including washing.

Diagnosis:

1. Check the charge level: if the battery is running out faster than before, its capacity has dropped. Use applications like AccuBattery for analysis.
2. Examine the washing mechanism: lift the robot and manually rock the mope nozzle. Luft more than 2 mm indicates wear.
3. Listen to the robot in a quiet room: extraneous sounds (squeaking, knocking) indicate mechanical problems.

💡 Tip: If the robot is older than 3 years, replacing the battery can return him a "second life." Original batteries for Xiaomi cost from 2 000 rubles, but you can find quality analogues cheaper.

FAQ: Frequent questions about washing in Xiaomi robot vacuum cleaners