Disassembly Xiaomi Mi 9 SE: a complete guide with photos, schemes and secrets of the masters

Xiaomi Mi 9 SE — The compact flagship of 2019, which is still in demand due to its balanced performance: AMOLED-A 5.97-inch screen, a Snapdragon 712 processor and a triple main camera, but over time, even such a reliable device can require repairs, from replacing the battery to cleaning the connectors or recovering from a fall. Disassemble the smartphone yourself – a task not easy, but doable with the right approach.

In this article, you will find a step-by-step photo instruction, a list of necessary tools, and unique nuances of disassembling this particular model (for example, the features of attaching the plume of the fingerprint scanner under the screen). We will also tell you how to avoid errors that lead to damage to flexible cables or detachment of the display. If you have never taken out smartphones before, do not worry: our guide is designed for beginners, but also contains profile tips for experienced craftsmen.

Preparation for disassembly: tools and precautions

Before you start, make sure you have everything you need. Xiaomi Mi 9 SE is a device with adhesive mounting of the rear cover and display, so you can not do without specialized tools.

• 🔧 Plastic mediators (2-3 pc.) - for careful liding and disconnection of adhesive joints.
• 🔥 Dryer or thermo-air station - for softening the glue (temperature 60-80)°C).
• ⚙️ Screwdriver. T3 and T5 — for the middle-shell attachment screws.
• 🧲 Magnetic mat or tray - so as not to lose small details (screws, washers).
• 📱 Suction cup for display – will help separate the screen after heating.
• 🔌 Tweezers with curved ends - for working with plumes.

Important: The Mi 9 SE has fragile flexible plumes, especially the fingerprint scanner and the camera. One careless jerk will have to change the entire module. Also, when disassembling, the manufacturer's warranty is canceled if it is still valid.

⚠️ Warning: Do not use metal tools to lid the lid! Even a small scratch on the aluminum case can become a hotbed of corrosion.

Step 1: Removal of the back cover – heating and slashing technique

The back cover of the Mi 9 SE is glued around the perimeter, so it must be carefully separated without damaging the antenna contacts.

1. Turn off your smartphone and remove the tray for SIM-map.
2. Heat the edges of the body with a hair dryer for 2-3 minutes, keeping it at a distance of 5-7 cm.
3. Apply the suction cup closer to the bottom edge (where the USB-C connector is) and pull up slightly.
4. Insert a plastic mediator into the resulting gap and slowly lead it along the body, separating the lid.

If the lid doesn't work, reheat the problem area. Don't put too much effort into it, because there are antenna cables under the lid that are easy to break. Be especially careful in the upper left corner, where the main Wi-Fi antenna is located.

After removing the cover, you will see:

• 🔋 Battery with connector and adhesive strips.
• 📶 Antenna modules glued to the cover.
• 🔧 12 screws of the mounting of the middle body (some hidden under the stickers!).

Step 2: Disconnect the battery and remove the middle case

Before touching any components, be sure to turn off the battery.

1. Put the black battery connector with a plastic mediator (it is located to the right of the battery).
2. Carefully disconnect the plume by pulling the tongue upwards, not sideways!

Now you can take the middle body.

1. Unscrew all 12 screws (use T3 and T5 screwdrivers). Note: screws of different lengths - remember where you were!
2. Remove the metal plate covering the motherboard.
3. Disconnect the plumes: 📱 Display (bottom, under the battery). 🔍 Fingerprint scanner (thin plume on the right). 📷 Main cameras (top).

⚠️ Note: Mi 9 fingerprint scanner plume SE If it breaks, it'll cost 30 to 50 percent of the cost of a smartphone!

Step 3: Dismantling the motherboard and child modules

The Mi 9 SE motherboard is mounted on 4 screws and connected to several plumes to remove it:

1. Unplug all connectors: 🔊 Dynamics and microphone (bottom of the fee). 📶 Antenna cables (sides). 🔋 Charging connectors (right).

Unscrew the 4 screws of the board mount (they can be hidden under stickers!).

Carefully tuck the board with a mediator and raise it at an angle of 30-45 °. Don't pull vertically - you can damage the connectors!

After the charge is retrieved, you will have access to:

• 🔊 Downstream dynamics and vibrator.
• 📡 Module NFC (if it is installed).
• 🔋 Battery glue strips (they must be removed before replacing the battery).

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If you are removing the motherboard for repairs (such as replacing the charging connector), take a picture of it on both sides beforehand, which will help to connect all the plumes correctly when they are reassembled.

Step 4: Replacing the battery – how not to damage the smartphone

The battery of the Mi 9 SE (typical capacity is 3070 mAh) is attached to two adhesive strips.

1. Heat the battery with a hair dryer to 60–70°C to soften the glue.
2. Carefully pull the black tongues of the adhesive strips (they are located under the battery). If there are no tongues, use a plastic spatula, putting the battery on the edge.
3. Don't put too much effort into it! If the battery doesn't respond, reheat it.
4. After extraction, clean the seat from the glue residues with alcohol.

When installing a new battery:

• 🔋 Use an original or certified battery (e.g. from Xiaomi or other ATL).
• 📏 Make sure that the adhesive strips are symmetrically arranged.
• ⚡ Connect the battery connector last, after connecting all other plumes.

⚠️ Warning: If the battery is swelling, do not puncture it! This can cause fire. Use special bags to dispose of Li-ion batteries.

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When replacing the battery, be sure to calibrate it after installation: completely discharge the smartphone, then charge to 100% without interruption. Repeat the cycle 2-3 times.

Step 5: Disassemble the display module – when necessary

Display Mi 9 SE — it AMOLED-It's a panel with an integrated fingerprint scanner, and it needs to be disassembled in three cases:

1. Replace broken glass (requires special LOCA glue and UV lamp).
2. Touchscreen repair (if the sensor does not respond to touch).
3. Replace the fingerprint scanner (if it no longer recognizes the fingers)

To dismantle the display:

1. Heat the screen with a hair dryer (temperature 70-80 ° C) for 3-5 minutes.
2. Use a suction cup and plastic mediators to separate the panel from the housing. Start at the bottom edge.
3. Once the display has separated, gently place it down on a soft surface (such as a napkin).
4. Disconnect the plumes: 📱 Main display (wide white connector). 🔍 Fingerprint scanner (thin black plume).

If you are replacing glass, consider:

• 🔧 You will need a separate wire to separate the glass from the AMOLED-matrix.
• 💡 Use it for bonding. LOCA-glue and UV lamp (wave 365 nm).
• ⏱️ The time of polymerization of glue is 10-15 minutes under the lamp.

Reverse Assembly: How to Avoid Mistakes

The Mi 9 SE assembly should be in reverse order, but with a few critical points in mind:

1. Check all plumes for damage before connecting.
2. Make sure that the antenna cables are not twisted and lie in their grooves.
3. Twisting the screws cross-cross to avoid skewing the board.
4. Check it after assembly: 🔋 Charging (plug the cable and make sure the current is going on). 📶 Communication (Wi-Fi, mobile network). 🔍 Fingerprint scanner and touchscreen.

If after assembly the smartphone does not turn on:

• 🔌 Check the battery and display connection.
• 🔧 Make sure all screws are swirled (an unpatched screw can close the board!).
• 📱 Try to clamp down the Power + Volume Up for 10-15 seconds to reset.

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After assembly, be sure to check the tightness of the case. If there are gaps, moisture can get on the board. To check, use bright light: illuminate the case at an angle - there should be no cracks.

FAQ: Frequent questions about the dismantling of Xiaomi Mi 9 SE