Disassembly of Xiaomi toothbrush: tools, step-by-step process and nuances for Mi Electric Toothbrush models

Xiaomi’s electric toothbrushes are popular gadgets that combine affordable prices and advanced features: cleaning timers, multiple modes of operation, pressure sensors. But even the most reliable technology requires maintenance over time: replacing the battery, cleaning from the plaque or repairing the switch button. You can disassemble the Mi Electric Toothbrush (or compatible models like Oral-B under the Xiaomi brand) on your own, if you know the nuances of design and avoid typical errors.

In this article, we'll take a step-by-step look at the photos, a list of tools you need, and a list of pitfalls that can damage your device if you don't do it properly. T100/T300/T500), So, you can use the more advanced magnetically charged versions, and if you're looking for a battery replacement, cleaning internal contacts, or diagnosing malfunctions, you'll find everything you need here.

⚠️ Important: Disassembling Xiaomi brush will void warranty (if it is still valid) and most battery or electronics related breakdowns are repaired at service centers for free during the warranty period. Self-repair is only valid for devices older than 1-2 years or in the absence of official support in your area.

What Xiaomi models can be disassembled independently?

Not all Xiaomi toothbrushes are disassemblable at home, and here is a list of the models for which the process is described in this article:

• 🔹 Mi Electric Toothbrush T100 — base model with a lithium-ion battery of 800 mAh.
• 🔹 Mi Electric Toothbrush T300 — Improved version with pressure sensor and 3 cleaning modes.
• 🔹 Mi Electric Toothbrush T500 — flagship model with magnetic charging and a 1000 mAh battery.
• 🔹 Xiaomi Oral-B Smart Toothbrush is compatible with Oral-B nozzles, but with Xiaomi’s proprietary firmware.
• 🔹 Mi Portable Electric Toothbrush – compact road version.

Xiaomi Soocare models (e.g. Soocare) X3 soocare S500) They have a different body design and they're different, they'll need special devices (like plastic blades instead of screwdrivers). If your brush isn't on this list, check its markings on the bottom of the case before you start work.

💡 Tip: If you are not sure about the model, look at the Mi Home app (Devices section) - there is an exact version of the gadget.

Necessary tools for disassembly

For careful disassembly of the brush Xiaomi without damage to the body will need:

⚠️ Warning: Do not use metal screwdrivers to separate plastic latches, this will lead to chips and cracks. If you do not have a plastic blade at hand, wrap the metal tool with insulation.

For models with magnetic charge (e.g, T500) additionally require a magnetic holder (can be removed from old computer equipment) so as not to lose small details during disassembly.

Step-by-step: how to disassemble a Xiaomi toothbrush

The disassembly process varies from model to model, but the overall pattern is the same for most devices. Consider the universal algorithm in the Mi Electric Toothbrush example. T300:

Step 1: Removal of the upper cover (nozzle)

1. Make sure that the brush is off and not connected to charging for at least a day (to avoid short circuit).

2. Pull the nozzle up with force - it is attached to a magnetic holder (in some models it is additionally fixed with a plastic stopper).

3. Under the lid, you'll see a metal rod (engine shaft) and a rubber sealing ring. Carefully remove the ring and put it away - it should fit into place without skewing when assembled.

Step 2: Separation of the hull

The body of the Xiaomi brush consists of two halves, fastened:

• 🔧 Latches (most models).
• 🔧 Screws (rarely, for example, Soocare) X3).
• 🔧 Glue (budget versions or after warranty repairs).

For latched models:

1. Insert a plastic blade into the gap between the halves of the body (usually it is noticeable at the on button).
2. Carefully drive the shoulder blade around the perimeter, alternately snapping the locks, and the process with a characteristic crackle begins - that's normal.
3. Don’t apply force in one place – distribute the force evenly so as not to break the plastic.

For glue models:

1. Heat the body with a hair dryer (temperature 60–80)°C) for 2-3 minutes.
2. Try to separate the halves with a spatula. If the glue doesn't lend itself, repeat the heating.

⚠️ Attention: If the body is not amenable, do not use a hammer or pliers! 90% of the time the problem is the wrong angle of impact with the shoulder blade. USB-plug).

Step 3: Removing the board and battery

After the separation of the body, you will see:

• 🔋 Battery (lithium-ion, soldered or on the connector).
• 🖥️ Printed circuit board with control chip and button.
• 🔄 Engine (with eccentric for vibration).

Algorithm of action:

1. Disconnect the engine plume from the board (usually it is attached to the connector, less often - solder).
2. If the battery is on the connector, just pull it up. If soldered, you'll need a soldering iron (with no more than 30 watts to keep the board warm).
3. Remove the board by previously disconnecting the button (it can be glued or fixed with a latch).

Critical! On the Xiaomi board T500 There's a pressure sensor microphone (a small hole next to the button) and don't touch it with metal tools or blow in, which can knock the sensor out.

Step 4: Diagnostics and Replacement of Parts

Now that the brush is disassembled, you can:

• 🔋 Replace the battery (typical malfunction after 2-3 years of use).
• 🧹 Clean the contacts from oxidation (alcohol solution).
• 🔧 Check the engine (if the brush is not vibrating).
• 🔄 Update the heat paste on the chip (when overheating).

For battery replacement:

1. Buy similar in terms of parameters (for example, for T300 fitting 3.7V 800mAh sized 40×20×5 mm).
2. Sell a new battery while observing polarity (red — "+", black — "–").
3. Secure it with bilateral tape or heat glue.

⚠️ Warning: If the brush doesn't turn on after the battery is replaced, check the fuse on the board (a small black cylinder next to the battery) that could burn if soldered improperly.

💡

Wrap it with tape before soldering, leaving only the contacts open, and this will prevent short circuits from accidentally touching the case.

Typical Disassembly Problems and How to Avoid Them

Even with care, you can run into difficulties, and here are the most common mistakes and ways to prevent them:

💡 Tip: If the brush is running after assembly, but vibrates weaker than before, check the centering of the engine shaft.

Another common problem is the oxidation of contacts due to moisture. If the brush is long charged or discharged quickly, clean the contacts of the charging connector and board with an alcohol solution (at least 70%). WD-40.

💡

If the brush stopped turning on after falling, 80 percent of the time the problem is the engine plume break, and check the integrity of the engine visually and with a multimeter.

Cleaning and maintenance of internal components

Having dismantled the brush, it is worthwhile to carry out a preventive cleaning, which will prolong its service life:

• 🧼 Body: Wash both halves with warm water and soap, then dry with a hair dryer (cold air).
• 🔋 Battery: Clean the contacts with a blower or alcohol. If the battery is swelling, immediately replace it!
• 🖥️ Fee: Remove dust with a brush, use Contact when oxidizing-60 analogue.
• 🔄 Engine: Lubricate the shaft with silicone lubricant (1 drop) if creaking is heard.

To clean the engine shaft (if it is contaminated with toothpaste):

1. Remove the rubber sealing ring.
2. Wash the shaft with a cotton swab soaked in alcohol.
3. Apply a drop of silicone lubricant (not oil!) and spin the shaft with your hands for even distribution.

⚠️ Note: Do not use for lubrication of the engine WD-40 or hydrocarbon-based oils (like machine oils) that break down plastics and rubber seals!

If the brush makes extraneous sounds (squeaking, knocking), the reason may be:

• 🔹 Wear of the bearing of the engine (motor replacement is required).
• 🔹 Infection of a foreign body inside the body (dental thread, hair).
• 🔹 Eccentric Dissections (Details That Create Vibration).

Assembly of brushes after disassembly or repair

To collect the brush you need in reverse order, but taking into account several nuances:

1. Check the sealing rings – they should sit tightly, without distortion.
2. Connect all the plumes before clicking (especially the engine plume).
3. Make sure the correct polarity of the battery (plus to plus, minus to minus).
4. Close the body, starting from the side USB-Sockets to get the latches in place.

After assembly:

1. Put the brush on charging for 12-24 hours (the first cycle after repair is longer than usual).
2. Check all the operating modes (if any).
3. Make sure the charge indicator is lit correctly (e.g. red when discharged, green when fully charged).

⚠️ Attention: If the brush turns on or jerks on itself after assembly, the pressure sensor (the microphone on the board) is likely to be damaged, in which case you will need to change the board or turn off the sensor programmatically (via firmware, if available).

💡 Tip: To check the leakage after assembly, apply a soap solution to the joints of the body and turn on the brush. If bubbles appear, there is a gap somewhere, and moisture can penetrate into the body.

When the disassembly will not help: cases for the service center

Not all Xiaomi toothbrushes can be repaired by yourself.

• 🔧 The control chip burned (brush does not respond to charging and button, the battery is serviceable).
• 🔧 Damaged. USB-connector (does not hold contact, sparkles when connected).
• 🔧 Wireless charging does not work (for models) T500 newer).
• 🔧 Broken plastic axis of the shaft (requires turning work).
• 🔧 The brush does not sync with the Mi Home app (firmware problem).

The cost of repair in official Xiaomi services:

💡 Tip: Before visiting the service, reset the brush to the factory settings (if it turns on). To do this, hold the switch on 10-15 seconds until the indicator flashes. This will eliminate software failures.

FAQ: Frequent questions about the dismantling of Xiaomi toothbrushes