How to disassemble an electric toothbrush Xiaomi: instructions with photos and nuances for all models

Xiaomi's electric toothbrushes are some of the most popular oral hygiene gadgets, but even they require maintenance. Over time, dust accumulates under the body, contacts oxidize, the battery goes down or the vibratory mechanism breaks down. You can disassemble the brush yourself, but the process requires care: wrong actions will lead to a break in the board or loss of water resistance.

In this article - Step-by-step analysis taking into account the features of the Mi Electric Toothbrush models T100/T300/T500/T700, And we'll also talk about the Oclean X Pro, which is a Xiaomi brand, and we'll tell you what tools you need, how to avoid common mistakes, and what to do if the brush stops turning on after disassembly. 90% In cases, the problem lies in oxidized contacts or a depleted battery.

If you've never done any electronics, start with a simple one: cleaning the body without disassembling it completely, and you just need to remove the nozzle and wash the base under a stream of warm water (but not boiling water!), and if the brush doesn't charge, vibrates poorly, or turns on itself, you'll have to go deeper.

⚠️ Important: Disassembling the brush Xiaomi automatically removes it from the warranty (if it is still valid), and after opening the case may lose its leakage - this will affect waterproofness (standard). IPX7).

What tools will be needed to disassemble

For careful disassembly without damage, prepare:

• 🔧 Plastic mediators or openers (to unscratch the body) leave metal screwdrivers for an emergency, leaving traces.
• 🔋 Hair dryer or thermo-air station (for softening the glue on models) T700/Oclean X Pro, where the body is glued together).
• 🧲 Magnetic screwdriver (cross-shaped, size) PH00 or PH0 — The Miniature Shoots in Xiaomi’s Miniature).
• 🧴 Isopropyl alcohol (90%+) — Cleaning contacts and removing glue residues.
• 📦 Container for small parts (cogs, springs, rubber gaskets are easily lost).

If you are planning to replace the battery, take:

• 🔋 New battery (for the purpose of T100/T300 — 14500 Li-ion 3.7V, for T500/T700 — 18650 2600mAh).
• 🔥 A soldering iron with a thin sting (power up to 30 W) and solder.
• 🛡️ Thermal tube (to isolate contacts after soldering).

⚠️ Warning: Do not use knives, scissors or pliers to open the case - it is almost guaranteed to damage latches or plastic. Also avoid acetone or solvents to remove glue: they can melt plastic or damage rubber seals.

Preparation of the brush for disassembly: steps before opening

Before disassembling the brush, perform the mandatory preparatory steps:

1. Discharge the battery completely. Connect the brush to charge and wait until the light goes out, which minimizes the risk of short circuits when working with the board.
2. Remove the nozzle and rinse the base under running water to remove toothpaste and plaque. dry the brush with a hair dryer (cold air!) or leave it for 12 hours in a dry place.
3. Take a picture of the body from all sides – this will help to properly assemble the brush back, especially if you are disassembling it for the first time.
4. Check for screws under rubber plugs. T300 and T500 They can be hidden under decorative stickers.

If the brush does not turn on at all, try before disassembling:

• 🔌 Clean the charging contacts with a cotton swab soaked in alcohol.
• 🔄 Hold the switch for 10-15 seconds (sometimes helps when the board is getting stuck).
• 🔋 Try another charger (use the original Xiaomi adapter on the phone) 5V/1A).

⚠️ Warning: If the brush fell into water or lay in a damp room for a long time, do not turn it on until completely drying (minimum 48 hours in rice or silica gel.

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If the brush is vibrating weakly, the problem may not be the battery, but the worn motor. Before disassembling, check it at maximum power - if the vibration is uneven, most likely, you need to change the engine.

Step-by-step disassembly of the body: from screws to boards

The disassembly process varies depending on the model, and below is a general-purpose instruction that is suitable for most Xiaomi brushes, with specifications for specific versions.

Step 1 Remove the back cover

• On models T100/T300 The lid is mounted on two screws (under rubber plugs). Carefully place the plugs with a plastic card.
• Nana T500/T700 And Oclean X Pro case glued. 60–80°C), then insert the mediator into the slot and carefully lead in a circle.

Step 2: Removing the battery and board

1. When you take the lid off, you'll see the battery soldered to the board, and on some models, it's secured with double-sided tape -- gently unplug it.
2. Unplug the battery contacts (if you're planning a replacement) or simply unplug the connector (if you're cleaning the board). T700 battery soldered directly to the board - do not pull the wires, so as not to tear off the tracks!
3. Turn the screws that attach the board to the case, usually 2-3 pieces.

Step 3: Disassemble the vibrational mechanism

• Inside the body, you'll find an eccentric motor that can be secured with screws or latches.
• On models Oclean X Pro motor is integrated with the board – it is not recommended to disassemble it separately.

📌 Key point: If you're disassembling a brush just for cleaning, you just need to take off the board and the battery and not touch the motor. 80 percent of the time, the brush problems are related to contact oxidation or battery discharge.

Make sure all screws are in place|Check the integrity of the rubber seals|Clean the contacts of the battery with alcohol|Check the operation of the switching button|Close the enclosure without distortion-->

Cleaning and repair of internal components

After disassembly, check all the details for damage.

🔍 Diagnosis of malfunctions:

• 🔋 The brush is not charging. → Check the contacts of charging and battery, test the voltage on the battery (should be 3.7–4.2V).
• 🔄 Self-inclusion → Clean the moisture button or replace it (on the board it is a micro-switch).
• 🔊 Weak vibration → Check the eccentricity of the engine for backlash or wear.

⚠️ Warning: If you see dark spots or swollen capacitors on the board, it's likely to have burned after moisture or short circuit, in which case it's cheaper to buy a new brush, and it'll cost 70-80% of the cost of repairing it.

Battery replacement: battery choice and soldering

The battery is the most vulnerable element in Xiaomi toothbrushes, which on average holds a charge of 1.5-2 years, after which the battery life is reduced to 5-10 minutes, replacing the battery will cost 3-5 times less than buying a new brush.

How to choose a battery:

• For Mi Electric Toothbrush T100/T300: 14500 Li-ion 3.7V 600–800mAh (finger-battery size AA, thinner).
• For T500/T700: 18650 3.7V 2600mAh (flashlight battery).
• For the Oclean X Pro: 18350 3.7V 1100mAh (less common form factor).

Instructions for replacement:

1. Remove the old battery, having previously cut off the shrinkage (if any).
2. Salt a new battery, observing polarity (red wire — "+", black — "-"").
3. Put a heat shrink tube on the contacts and warm up with a hair dryer.
4. Secure the battery on double-sided tape or plastic screeds.

💡 Tip: If you can't solder, buy a battery with already soldered wires (on AliExpress, these are sold under the request "battery for Xiaomi toothbrush"). They cost 20-30% more, but will save you from the risk of overheating the fee.

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After replacing the battery, be sure to perform 2-3 full charging/discharge cycles – this calibrates the battery controller and prolongs its service life.

Brush assembly and leakproofness check

It's harder to get the brush back together than it is to disassemble it, because accuracy is important.

1. Put the charge in place and secure the screws.
2. Connect the battery (if disconnected).
3. Make sure all the rubber seals are in place – they are responsible for IPX7 (waterproof).
4. Close the case, starting with the latches near the power button.
5. Twirl the screws (if any) on the models with the glued body (T700) use glue B-7000 sealant.

🔍 Pressurization check:

• So, if you have bubbles, you can put the brush in water for 10 seconds, and if you have any bubbles, there's a gap that needs to be sealed.
• Wash the case and leave to dry for 12 hours before first use.

⚠️ Warning: If the brush doesn't turn on or warms up after assembly, immediately disassemble it back, it's likely that it's closed somewhere!

Frequent Mistakes and How to Avoid Them

Even experienced toothbrushes make mistakes sometimes, and these are the most common ones.

• 🔧 Spinning: Use a magnetic-tipped screwdriver and don't put too much effort into it. WD-40 And wait 5 minutes.
• 🔥 Overheating board when soldering - soldering the battery perform in quick movements (no longer than 3 seconds per contact).
• 💧 Moisture on board – if the brush is wet, dry it for at least 48 hours in rice or silica gel.
• 🔋 Incorrect battery polarity – always check the labeling "+" and-- on board and battery.
• 🔄 Loss of small parts -- springs, rubber pads, or cogs -- is easily lost. Use a magnet container.

📌 How to avoid problems:

• Take pictures of each stage of the disassembly.
• Do not disassemble the brush on the carpet or soft surface - details are easily lost.
• If you are not sure of your abilities, practice on an old or broken brush.

⚠️ Warning: If the brush is unstable after repair (it turns on itself, vibrates with jerks), the problem may be in the damaged firmware of the controller, in which case only a replacement board will help (it can be found on AliExpress for 10-15 hours).$).

FAQ: Answers to Frequent Questions