Disassembly Xiaomi 3: detailed instructions for repairs with your own hands

Xiaomi 3 is an iconic smartphone released in 2013 that is still used by many users. However, over the years, even the most reliable technology requires repairs, from replacing the battery to cleaning connectors or recovering from a fall. Disassembling Xiaomi 3 yourself is a difficult task, but it is doable with the right approach.

This article will help avoid common mistakes: damage to plumes, scratches on the body or accidental break of contacts, we will discuss in detail what tools you will need, how to safely remove the back cover, disconnect the battery and get to the motherboard, and also tell you what to do if the phone does not turn on after dismantling - and how to prevent this from happening.

Important: Xiaomi 3 has several modifications (for example, WCDMA and TD-SCDMA), but structurally they are identical. Instructions will suit all versions, including Mi 3 with 16/64 GB of memory.

Preparation for disassembly: tools and security measures

Before you start, make sure you have everything you need, and not even one tool can damage the body or the internal components.

• 🔧 Plastic mediators (2-3 (a) - for the tidying of the lid and the detachment of the latches.
• 🔨 Cross screwdriver (PH00 or PH0) - for screws of the housing and motherboard.
• 🧲 Magnetic mat or container - so as not to lose small screws (there are about 15 pieces!).
• 🔥 Dryer or thermo-air station – if you plan to unfurl plumes or chips (not recommended for beginners).
• 📸 Smartphone to capture the process – capture each step so you don’t confuse the assembly order.

Also prepare the workplace: the desk should be clean, without crumbs and dust. Use an antistatic bracelet or periodically touch a grounded metal object (for example, a heating battery) to remove static electricity - it can damage the chips.

⚠️ Warning: If you're disassembling a Xiaomi 3 with a broken screen, be sure to stick tape over it so that shards of glass don't get inside the case or hurt your hands. Don't try to turn the phone on until you're completely disassembled - this can lead to a short circuit!

If you've never taken a smartphone apart, practice on an old device or watch YouTube videos (like JerryRigEverything or Repair Universe) to help you understand how hard you can push the latches and how to hold the mediator properly.

Step 1: Removing the back cover

The back cover of Xiaomi 3 is mounted on latches and has no screws, but it is not so easy to remove it - plastic can deform over the years. Start by heating the case: use a hair dryer at minimum power (temperature ~50 ° C) and warm the edges of the cover for 1-2 minutes, this will make the plastic more elastic.

Then proceed as follows:

1. Insert a plastic mediator into the gap between the lid and the case at the charging connector.
2. Carefully drive the mediator along the edge, alternately snapping the clamps. Do not try to remove the lid immediately - this will lead to breakage!
3. When all the latches open, lift the lid on the camera side. Be careful, the antenna plume is glued to it.

If the lid doesn't lend itself, don't use excessive force. You may have missed the latch or the plastic is too hard. In this case, repeat the heat and try again. Don't use metal tools - they will leave scratches!

⚠️ Warning: Some Xiaomi 3 versions may have an extra seal film under the lid. Don't tear it, it protects against dust and moisture. Gently peel it off and save it for reverse assembly.

Step 2: Battery disconnection

When you take the lid off, you'll see the battery that's attached to the double-sided tape. First rule: before you unplug it, be sure to unplug the plume from the motherboard!

1. Find a small black jack labeled BATTERY (usually located at the top of the board).
2. Carefully put a plastic pickup on it or tweezers on it.
3. Make sure the contacts are not closed – touch them with a plastic pen screwdriver to discharge the residual current.

Now you can take the battery off. You can pull it on either side and slowly pull it up. If the tape is too sticky, use a thread or a guitar string: run it under the battery and saw it back and forth, as in the video below (an example for the iPhone, but the method is universal):

If the battery is swelling, do not try to puncture or bend it - this can lead to fire! In this case, it is better to contact the service center. To replace the battery with a capacity of 3050 mAh (original specification) or analogues with protection against overheating.

Step 3: Dismantling the motherboard

The Xiaomi 3 motherboard is mounted on 10-12 screws (depending on the modification). They are all different in length, so be sure to remember or take a picture of which screw was twisted from where.

First, unscrew the screws around the perimeter of the board (usually shorter), then the ones closer to the center. Then gently raise the charger side. It can stick to the heat conductive paste on the processor — don't pull, but sway slowly from side to side.

Pay attention to the plumes that need to be disconnected before the full charge is withdrawn:

• 📞 Display plume (widest, with metal latch).
• 🔊 Speaker and microphone plume (thin, white).
• 📶 The antenna plume (can be glued to the cover).
• 🔋 Power button plume (sometimes integrated into the main unit).

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If the plume doesn't detach, don't pull it by force! Chances are you didn't open the latch. Look at the jack on the side -- there's got to be a little lever that you have to lift with a screwdriver.

After removing the board, put it on an antistatic surface. Don't touch the chip contacts with your bare hands - sweat and fat from the skin can cause corrosion. If you want to clean the board of dust, use a soft brush and isopropyl alcohol (90% concentration and higher).

Step 4: Disassemble the front panel and screen

The Xiaomi 3 screen is paired with a touchpad and attached to a frame on double-sided tape and latches. To remove it, you will need a hairdryer again - warm up the edges of the display for 2-3 minutes. Start at the bottom (where the Home button is), as there are fewer plumes.

Put a plastic mediator in the slot and slowly lead it along the edge. If the screen doesn't lend itself, don't increase the force, you better repeat the heating. The main danger at this stage is damage to the plume of the display that passes under the battery. It's very fragile and it costs almost like a new screen!

After removing the display, you will have access to:

• 🎤 Microphone (located at the top next to the speaker).
• 🔍 Front camera (attached to two screws).
• 📱 The plume of the Home button (often broken when untidy).
• 🔦 Light sensor (a small black dot next to the camera).

⚠️ Warning: If you're disassembling a Xiaomi 3 with a cracked screen, be extremely careful - shards can damage the plumes when removed. It's better to pre-paint the display with wide tape to keep the windows in place.

To replace the screen, choose original spare parts or quality replicas with OCA-glue (it provides better transparency and sensitivity of the sensor). The average price of a new display for the Mi 3 is 1500-2500 rubles (2026).

Common Mistakes and How to Avoid Them

Even experienced craftsmen sometimes make mistakes when disassembling Xiaomi 3. Here are the most common of them and ways to prevent them:

Another common problem is that flexible plumes are damaged, and they look tough, but they actually break easily when handled carelessly, and always take the plumes by the edges, not the middle, and don't bend them at right angles.

If the phone does not turn on after assembly, check:

1. Is the battery connected (sometimes the plume leaves when installing the board).
2. Are the contacts closed on the board (look at the subject of foreign objects).
3. Are all the plumes (especially the display and power buttons) installed correctly?

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If after disassembly, Xiaomi 3 does not respond to the power button, but when connected to charging vibrates - the problem is in the plume of the button. If it does not vibrate, check the battery or power controller on the board.

Cleaning and diagnostics of components

If you take down the Xiaomi 3, you should do a preventive cleaning, and the dust and oxidation of the contacts are common causes of unstable performance.

• 🧹 Jack cleaning: Use wood toothpick and alcohol to clean the charging connector, speaker and microphone. Don't use metal objects!
• 🔧 Contact check: Examine the plumes for oxidation (greenish coating). If you have, gently clean with a blower or a special liquid Contact Cleaner.
• 🔋 Battery Diagnosis: Measure the voltage with a multimeter - it should be in the range of 3.7-4.2 V. If below 3.5 V, the battery should be replaced.
• 🌡️ Thermopaste check: The processor and memory chip must have a thermal paste. If it is dry, remove the residues with alcohol and apply a new one (e.g. Arctic MX-4).

If the phone is overheated, check the motherboard for bloated capacitors (they look like small barrels with a convex top).

To check the performance of components after cleaning, you can use Xiaomi test modes.

1. Turn off the phone.


2.Cut Volume + and Nutrition at the same time.




3. From the menu, select Item Test to check the display, camera, speakers, etc.

Assembly of the phone: procedure and testing

To assemble Xiaomi 3 you need to reverse order, but with some nuances:

1. Install the motherboard and twist the screws starting with the central ones (this will prevent skewing).
2. Connect all the plumes, starting with the battery, make sure the latches on the connectors are closed.
3. Stick the new double-sided tape to the battery (if replaced) and set it back in place.
4. Fix the back cover, starting from the top (there are fewer latches).

After assembly, don't turn the phone on immediately. First, plug it into a charger and check:

• Is the charger on?
• Whether the cable is recognized (if not, the problem is in the connector or the plume).
• Do you have any other sounds (squeaking, coding) when pressing the body?

If everything is fine, turn on the device and test:

• 📱 Sensor (swipe your finger across the screen).
• 🔊 Speakers and microphone (take a test call).
• 📷 Cameras (take pictures of something front and main).
• 🔋 Charge (make sure the battery is charging and holding the charge).

⚠️ Warning: If after assembly the phone turns on but the screen flashes or artifacts (bands, stains) appear, this is a sign of poor contact of the display plume. Take the device apart and check if it is connected correctly. Don't press the screen - this can exacerbate the problem!

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After successful assembly, reset (Settings → Restore and Reset) to avoid software glitches that sometimes occur after disassembly.

FAQ: Frequent questions about the Xiaomi 3 disassembly