Disassembly of the Xiaomi brush: how to remove the nozzle, replace the battery and repair the engine

Xiaomi’s electric toothbrushes are some of the most popular oral care gadgets, thanks to a combination of price, quality and smart features. However, even the most reliable appliances require maintenance over time: the battery can run out, the engine jams or the attachment breaks. Service centers charge up to 30% of the cost of a new brush for simply replacing the battery, so many users prefer to fix the device themselves.

In this article you will find step-by-step instructions for disassembling any Xiaomi brush models - from the budget Mi Electric Toothbrush T100/T300 To the flagship Oclean X Pro Elite (compatible with the Mi Home ecosystem), we will tell you how to carefully open the case without damaging the seals, replace the battery or motor, and give tips for diagnosing malfunctions. All operations are illustrated with photos and are accompanied by warnings about typical mistakes of beginners.

What Xiaomi brushes can be disassembled independently

Not all Xiaomi electric brushes are equally repairable, such as ultrasonic models (like the Oclean). W10) They have a sealed case with adhesive seams that are difficult to open without damage, but most rotary and pulsating brushes are relatively easy to disassemble:

• 🔹 Mi Electric Toothbrush T100/T300/T500 — Budget models with removable battery (type) 18650)
• 🔹 Oclean X/X Pro/SE — mid-segment battery 800 mAh, magnetic levitation motor
• 🔹 Oclean Air 2 - ultra-light model with a battery of 550 mAh (requires caution when opening)
• 🔹 Mi Oral Irrigator + Toothbrush - combo device with irrigator (disassembly only of the brush part)
• 🔹 Soocare X3/X5 — Xiaomi-branded Oclean clones are fully compatible in parts

Before disassembling, make sure to check if your model is not affected by the warranty. Opening the case automatically voids Xiaomi warranty obligations, even if you do not break anything. If the brush is warranty, it is better to contact the service center - especially if the problem is electronics (for example, does not turn on or does not hold the charge).

⚠️ Attention: Oclean models W10/W10 Pro with ultrasonic engine have a sealed class body IPX7. Disassembling them requires a special tool (a dryer to soften the glue) and soldering skills. Without experience, you risk damaging the control board.

Preparation for disassembly: tools and security measures

For a careful disassembly of the Xiaomi brush, you will need:

• 🔧 Plastic mediators (or guitar mediators) – to open the latches of the body
• 🔧 Cross screwdriver (usually) PH00 or PH0) screw
• 🔧 Tweezers – for extraction of small parts (springs, contacts)
• 🔧 Voltage Tester or Multimeter – to check the battery and motor
• 🔧 Silicone sucker (optional) - helps remove the lid from models with vacuum fastening
• 🔧 Isopropyl alcohol - for cleaning contacts and removing glue residues

Also prepare the workplace:

1. Cover the table with a soft cloth so as not to scratch the body.
2. Use an antistatic mat or at least touch a grounded item before work - statics can damage the fee.
3. Take a picture of each stage of the disassembly – this will help to properly collect the brush back.
4. If you replace the battery, buy the original one (for example, for the battery). T300 battery BL-5B 1400 mAh. Cheap analogues are losing capacity quickly.

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If you don't have plastic mediators, you can replace them with old bank cards or plastic spoons, and the main thing is that the tool is not metal, or you will scratch the case.

⚠️ Warning: Never use a knife or metal screwdriver to open the case! Even a small scratch on the O-ring will lead to water entering the brush, which will cause corrosion of the board. IPX7 This is likely to short-circuit the next time you use it.

Step-by-step: how to disassemble a Xiaomi brush (on the example of Mi Electric Toothbrush) T300)

Consider the disassembly on the most popular model - Mi Electric Toothbrush T300. Design of other brushes (Oclean X, Soocare) X3) It's the same with minor differences:

Step 1: Remove the nozzle and lower cover

1. Turn the base of the nozzle counterclockwise and remove it. Inside you will see a metal rod that transmits rotation from the motor.

2. Turn over the brush and find a small recess on the bottom cover (near the charging contacts). Put the lid on the plastic mediator as you move around. 3-4 latch.

3. Under the lid you will see a battery (usually soldered to the board) and a motor with gears. Don't pull the wires - they are very fragile!

Step 2: Unconnecting the control board

1. Carefully unseal the contacts of the battery from the board. If you do not know how to solder, you can simply disconnect the connector (in some models it is removable).

2. Unscrew it with a screwdriver. 2-3 The screws can be hidden under stickers -- remove them with your nail or tweezers.

3. Remove the board. Notice the O-ring around the motor -- don't lose it!

Step 3: Removing the motor and gears

1. Remove the gear from the metal rod. It may sit tight - help yourself with tweezers, but do not put too much effort.

2. Unscrew the screws that attach the motor to the body with a screwdriver. In some models, the motor is glued - carefully tuck it into the mediator.

3. Check the gears for wear. If the teeth are worn or cracked, they need to be replaced (you can order a remake on AliExpress for "Xiaomi toothbrush gear set").

Check the integrity of the sealing rings|Clean the battery contacts with alcohol|Make sure the gears rotate freely.|Tighten all screws with moderate effort-->

Video instructions for disassembly (click to view):

Battery replacement: battery choice and soldering

The most common reason Xiaomi brush breaks down is a dead battery. Average battery life — 2-3 year ~500 If the brush has become discharged over the 1-2 It's time to change the battery, or it doesn't hold a charge at all:

Battery replacement process:

1. Solder off the old battery from the board. If the battery is on the connector, just disconnect it.
2. Sell a new battery while observing polarity (+ and − charge-board).
3. Insulate the contacts with shrink tube or tape to avoid short circuit.
4. Before assembly, check the voltage with a multimeter - it should be within 3.7-4.2 V.

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If the brush doesn't turn on after the battery is replaced, check the fuse on the board (a small black chip next to the charging contacts).

Diagnostics and repair of the engine

If the Xiaomi brush is buzzing but not rotating, or the nozzle is spinning in jerks, the problem is most likely in the engine or gears.

• 🔍 The engine won't start: check the multimeter voltage on the motor contacts when you press the power button. If there is a voltage, but the engine is not working, it burned.
• 🔍 The brush vibrates but doesn't rotate: the problem is the gears. Take them off and check for wear or cracks.
• 🔍 Extraneous sounds (squeaking, crackling): usually caused by water entering the mechanism. Disassemble the brush, dry the parts with a hairdryer (without overheating!) and lubricate the gears with silicone lubrication.
• 🔍 Uneven rotational speed: Magnets in magnetic levitation motors (e.g., Oclean X Pro) may be worn out.

You can change the engine in Xiaomi's brush, but it's harder than changing the battery. ~30-50% of the price of the brush, so the feasibility of repair depends on the model. T300 (cost ~2000 rub.) engine replacement (~1000 rubles.) justified, and for Oclean Air 2 (cost) ~4000 rubles.) It is cheaper to buy a new brush.

Where to buy spare parts:

• 🛒 AliExpress – search for “Xiaomi toothbrush motor”, “Oclean gear set".
• 🛒 eBay – often has original parts from the manufacturer.
• 🛒 Local services – some workshops sell used parts from donor brushes.

⚠️ Note: Oclean magnetic levitation brushes use a special lubricant that is not compatible with conventional silicone lubricants. If you disassemble such a motor, use only the original lubricant (you can order from the manufacturer).

Brush assembly and performance check

To collect the Xiaomi brush after repair you need in reverse order, but there are a few critical points:

1. O-rings: lubricate them with silicone lubrication before installation (e.g, WD-40 This will prevent water from getting inside.
2. Cogs: Make sure they're connected to the motor correctly. If the gear is crooked, the brush will vibrate.
3. Closing the case: Latch the lid evenly, starting at the side of the power button. If the lid does not sit down, check if the battery wire is disturbing.
4. Test start: before full assembly, connect the brush to charge and check if the motor is rotating. If not, take it apart again and check the contacts.

After assembly:

• 🔋 Charge the brush completely (the first charging cycle after repair can take up to 12 hours).
• 💧 Check the leaks by watering the joint of the body and the nozzle. If water leaks, repeat the assembly.
• 🔊 Turn on your brush and listen to the sound of the engine. Normal work is a uniform hum without creaking.

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If the power button works "once again" after assembly, check the spring contact under the button. Often it bends when assembled and does not completely close the chain.

Frequent mistakes in disassembly and how to avoid them

Even experienced craftsmen sometimes make mistakes that lead to a permanent break in the brush, and here are the most common ones and ways to prevent them:

If you make a mistake, don't panic. For example, a burned-out fee can be restored by replacing burnt-out elements (fuse, transistors) or by soldering contacts. In extreme cases, working parts (motor, battery) can be used as donor parts for another brush.

FAQ: Answers to Frequent Questions