How to safely remove the watch from the case Xiaomi Mi Band 4: a detailed guide with photos and warnings

The Xiaomi Mi Band 4 fitness bracelet is one of the most popular wearables, but even it has problems over time: it peels off the screen, drains the battery or requires a replacement strap. To fix the gadget, you often need to get an electronic module out of the case - a task that seems simple only at first glance. Wrong actions can lead to damage to the plumes, break contacts or completely break the device.

In this article, you will find a step-by-step manual with visual cues, a list of tools you need, and critical warnings to help avoid typical errors. We will also look at when you can do the disassembly yourself, and when you should contact the service center. If your Mi Band 4 has stopped responding to charging, shows artifacts on the screen or just needs cleaning, this guide is for you.

Why you may need to remove the module from the body

There are several reasons why users decide to disassemble the Xiaomi Mi Band 4:

• 🔋 Replacing the battery is the most common reason. After 2-3 a year of operation, the battery loses capacity, the bracelet discharges in a few hours, or refuses to turn on.
• 📱 Screen problems: Sensor detachment, broken pixels, uneven backlighting, or no image at all.
• 💧 Moisture intrusion. Despite the stated 5ATM, the device may become jammed after bathing or showering, requiring drying and cleaning of contacts.
• 🔧 Replace the strap. If the original strap breaks or you want to install the metal strap, you have to remove the module.
• 🔄 Manual firmware updates. In rare cases, Fastboot firmware requires a connection to the module contacts.

It is important to understand that Xiaomi Mi Band 4 is not designed for custom repairs: the body is sealed, and the internal components are connected by thin plumes. Any careless movement can turn into expensive repairs.

⚠️ Warning: If your bracelet is still warranty, disassembly will automatically cancel it. Check the warranty status in the Mi Fit app before you start work.

Preparation: Tools and Conditions for Safe Disassembly

Before you start, make sure you have everything you need, and the absence of at least one tool can damage the body or internal components.

Also prepare the workplace:

• 📍 Good lighting is preferably a table lamp with a magnifying glass.
• 🧹 Clean surface without pile and dust (use a microfiber napkin).
• 📦 Spin containers – small cogs are easily lost.
• 📸 Smartphone for photos – fix every step so as not to confuse the order of assembly.

⚠️ Warning: Don't use metal blades or knives to open the body! They leave scratches and can damage the internal components. A plastic mediator is the only safe option.

Remove the bracelet from your hand and turn it off (clamb the 10 sec button).

Remove the strap (click on the button from the back of the module)

Prepare all tools and the workplace

Take a picture of the initial state of the bracelet

Wear an antistatic bracelet (optional, but recommended)-->

Step-by-step instructions: how to remove the module from the body

Now, to the most critical stage, follow the instructions in strict order, and skipping the steps can cause a breakdown.

Step 1: Heating the case to soften the glue

The body of the Mi Band 4 is glued around the perimeter, and you can't open it, so you need to heat the bracelet evenly to make the glue elastic.

1. Set the hair dryer at a minimum temperature (up to 60°C).
2. Direct the airflow to the back of the module (where the button is located).
3. Heat for 2-3 minutes, periodically checking whether the body has begun to "go away".

Temperatures above 70°C can damage the battery or screen.

Step 2: Separation of the body by the mediator

After heating, insert a plastic mediator into the gap between the front and back of the case. Start at the corner next to the button:

• 🔹 Carefully swipe the mediator around the perimeter, wiggling it slightly.
• 🔹 If the case fails, heat for another 1 minute.
• 🔹 Don't force -- it's better to repeat the heat than break the latches.

Once the case opens, don't be in a hurry to completely disconnect it. There's a plume inside the screen that can break when you move abruptly.

Step 3: Disconnect the screen plume

When the case is open, you'll see an internal board with a battery pack and a plume going to the screen, and the plume is attached with a fragile connector, and you have to unplug it with tweezers.

1. Then, gently put the black latch of the connector (it opens up).
2. After clicking, the plume can be removed.
3. Don’t pull the plume – take only the hard part!

If the plume breaks, the screen will stop working, and the display will need to be replaced (cost ~1500₽).

Step 4: Removal of the module from the housing

Now you can get an electronic module. It's attached to:

• 🔩 Two small screws (unscrewed with a cross screwdriver).
• 🧲 Double-sided Scotch (take care of the mediator).

Once the mounts are removed, the module is removed from the body. Don't pull the battery! It's glued to the board, and you can tear the contacts off.

💡

If the screws do not unscrew, put isopropyl alcohol on them and wait 5 minutes. This will dissolve the possible corrosion and facilitate the process.

Common Mistakes and How to Avoid Them

Even with careful disassembly, many users make critical mistakes.

The most dangerous mistake is trying to remove the module without disconnecting the screen plume, which in 90% of cases leads to permanent damage to the display, and the bracelet will have to be discarded or buy a new screen.

⚠️ Warning: If the bracelet stops turning on after disassembly, check: Screen plume integrity (whether there are breaks); Battery contacts (whether they have bent); Short circuit (blackened elements); If you are not sure of your abilities, bring the device to service.

What to do after removing the module

Once the module is successfully removed, you can start repairing it, depending on the reason for disassembly, the next steps will be different:

• 🔋 Battery replacement: Solder off the old battery (use a soldering iron with a thin sting). Salt a new one (it's important to observe polarity!). Check the voltage with a multimeter (3.7V-4.2V).
• 💧 Clean after water: Wash the board with isopropyl alcohol. Dry with a hair dryer (cold air!) for 10-15 minutes. Check the integrity of the contacts.
• 📱 Screen replacement: Disconnect the old plume. Connect the new screen (buy original or compatible). Check the sensor response.

After the repair, assemble the bracelet in reverse order before the final assembly:

1. Check the operation of all buttons and sensors.
2. Make sure the battery is charging.
3. Test synchronization with the Mi Fit app.

1. Correct connection of the screen plume (should be clicked when fixing).

2. Battery contacts (possibly not related to the charge).

3.No short circuit (check the blackener charge).-->

When is the best time to contact the service center

Not all breakdowns can be repaired by yourself.

• 🔥 The board shows traces of burns or melted elements.
• 💥 The battery is swelling (it's dangerous - it could ignite!).
• 📉 The bracelet does not respond to charging and does not show signs of life.
• 🔧 Requires replacement of chips (e.g., charging controller).

Cost of repair in the service:

If you live in a small town that doesn't have Xiaomi service centers, look for smartwatch repair shops.

• Reset the bracelet to factory settings (Settings → Reset).
• Unplug him from his Mi Account.
• Take a picture of the external damage (if any).

FAQ: Frequent questions about disassembling Xiaomi Mi Band 4