Modern smartphones like the Xiaomi Mi 9 have great design and advanced hardware, but their interior layout often leaves much to be desired in terms of maintainability. Many owners face the need to replace a broken display or a swollen battery, but the absence of screws in visible areas of the case baffles even experienced users. The dismantling process requires not only special tools, but also a clear understanding of the sequence of actions so as not to damage the plumes or back cover.
In this guide, we will discuss in detail how to properly and safely disassemble the Xiaomi Mi 9, paying special attention to the nuances of working with adhesive joints and fragile components. You will learn what tools are necessary to start, how to heat the case without overheating the matrix and what to do if the plume is glued to the dead. Proper preparation of the workplace will save you time and nerves, and also minimize the risk of turning a simple repair into a purchase of a new device.
Before you start to physically affect the gadget, it is critically important to assess your strength and the availability of the right equipment. 80-90 degrees Celsius, as higher values can irreversibly damage OLED-We'll go on to the list of tools and prepare the device for the procedure.
Tools and workplace preparation required
A high-quality dismantling of the Xiaomi Mi 9 is impossible without a specialized set of tools that will allow you to work with micro-screws and thin plumes. The standard screwdriver and knife set will not work here, since you risk tearing the thread or damaging the internal partitions of the case. Professionals use precision sets that include screwdrivers of different shapes and sizes, as well as suckers and mediators.
Special attention should be paid to the source of heating. Hair dryers often do not give enough temperature or unevenly warm the glass, so it is better to use a professional heat plate or a quality temperature-adjusted building hair dryer. You will also need isopropyl alcohol to dissolve the glue and tweezers with antistatic coating for working with small parts.
- 🛠️ Precision screwdrivers (cross-hatched) PH000, PH00 and star-shaped Torx T2, T3).
- 🔥 Thermophene or heating plate (recommended temperature) 80-90°C).
- 💳 Plastic mediators, suction cup and thin metal scalpel (for neat opening).
- 🧪 Isopropyl alcohol, tweezers and glue B-7000 reverse-assembly.
Prepare the workspace: the table should be well lit and the surface should be clean and non-conductive. Cover the workspace with an antistatic mat or just a sheet of white paper, on which small screws will be clearly visible. Before work, be sure to turn off your smartphone and, if possible, discharge the battery to 25% to reduce the risk of fire in case of accidental damage.
Removal of the back cover and primary access
The first step in how to disassemble the Xiaomi Mi 9 is to separate the back glass panel from the metal frame. The design of the smartphone involves using a powerful adhesive layer around the perimeter, which must be softened. Warm up the back of the device evenly for 2-3 minutes, constantly moving the hair dryer to avoid local overheating.
After heating, insert a thin metal scalpel or a special spatula into the bottom end where the speaker is located, and make a neat incision of the glue. Don't try to pick the lid off immediately, act gradually as you move along the edges. It's important not to insert the tool too deep so as not to damage the fingerprint scanner plume or antenna modules close to the edges.
⚠️ Warning: Do not use force when bending the lid. Xiaomi Mi 9 glass is very fragile and can burst from the slightest distortion if the glue has not yet warmed to the desired consistency.
Once the perimeter is passed, install a suction cup at the bottom of the back and gently pull up while working as an angled mediator. If the lid is difficult, stop pulling and warm up the problem area again. After successfully removing the panel, access to the main board and battery will open, but it is too early to rush to remove them.
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Stick a strip of transparent tape onto the cracked back cover before heating - this will prevent the glass shards from falling and hold them together.
Dismantling the protective plate and disconnecting the plumes
Under the back cover is a large plastic or metal plate covering the main board and the top of the battery. In the Xiaomi Mi 9 model, it is attached to many screws of different calibers, so it is extremely important to follow the order of their unwrapping and remember the location. Use a magnetic mat or a sheet of paper with a drawn circuit so as not to confuse the fastener.
Once you remove all screws, carefully remove the plate. NFC-An antenna that is often glued to the plate itself or the inside of the lid. Be very careful: the antenna plume is very thin and easily breaks when you move sloppy.
To turn off the plumes, use a plastic blade, putting the connector up from the bottom. Metal tools are better not to use, so as not to close contacts on the board, which can lead to a short circuit. First of all, the battery plume is turned off to turn off the device and ensure the safety of further work.
- 🔋 The first to always disconnect the connector of the battery to de-energize the system.
- 📱 Then disconnect the plumes of the display, touch screen and subscreen fingerprint scanner.
- 📡 Carefully remove the main camera module if it interferes with access to other components.
- 🔌 Disable the lower board plume (sub-board) going through the main body.
☑️ Safe disabling of components
Replacement of the battery and work with glue
The battery in Xiaomi Mi 9 takes up a significant part of the internal volume and is attached to double-sided tape or glue. To extract it, you need to apply heating again, but from the inside of the case, warming the area under the battery. Do not try to pull the battery behind the protective film or wires, this is guaranteed to damage it and possible fire.
Use a suction hood or a plastic card soaked in isopropyl alcohol. Inject the liquid under the battery to dissolve the adhesive layer, and gradually rock the battery. If you plan to reuse the old battery, the heating should be minimal, since lithium-ion cells are sensitive to high temperatures.
| Parameter | Meaning/Description | Importance |
|---|---|---|
| Type of battery | Li-Po, non-removable | Tall. |
| Capacity | 3300mAh (typical) | Medium |
| Firming | Glue base + scotch | Critical |
| Heating temperature | Not more than 60°C (locally) | Critical |
After removing the old battery, thoroughly clean the seat of glue residues. Apply a new B-7000 glue layer or a special adhesive layer to the new battery and body. When installing the new battery, make sure the connector sits tight and until you click, and the battery itself does not swell from heat during installation.
⚠️ Warning: Never puncture the battery body or bend it. Damage to the internal structure of the Li-Po cell can cause instantaneous ignition or explosion.
Replacement of the display module and touch screen
If you wanted to repair a broken screen, then once the frame is removed and the plumes are turned off, you need to dismantle the display module itself. The Xiaomi Mi 9 uses AMOLED technology, which is attached to a metal frame on the glue. Replacing glass separately from the matrix at home is almost impossible without a laminator, so the entire module assembled with the frame changes.
To remove the module, you need to warm up the perimeter of the screen and carefully cut the adhesive layer with a thin string or blade. OLED-The panel is very thin and sensitive to mechanical pressure. After removing the old module, degrease the frame of the new screen and check the touchscreen before the final sticker.
Installing the new module requires precise positioning. Make sure the holes under the speaker, camera and sensors match perfectly. Apply a thin layer of glue around the perimeter of the frame and tightly press the module, fixing it with rubber bands or loads for drying time (usually 1-2 hours).
Why can’t a fingerprint work after changing the screen?
Assembly of the device and verification of functionality
The final stage is reverse assembly, which requires even more care than disassembly. Set all the screws in their places, keeping the length of each one in place. A short screw in the long hole will not give the desired fixation, and a long screw in the short hole can break through the board or damage the carving of the case.
Before sticking the back cover, be sure to check the health of all systems: make a test call, check the vibration, the work of cameras, microphones and speakers. SIM-It's only after a successful test that you can put glue on the body and fix the back panel.
- 🧹 Carefully remove dust from the interior surfaces before closing the case.
- 🔩 Wrapping the cross-cross screws for a uniform fit of board.
- 🧪 Apply glue in a thin layer, remove the excess immediately with alcohol.
- ⏳ Let the glue dry under the press at least 30-60 minutes before switching on.
After assembly, take your time to install a protective glass or case. Let the device lie down for a few hours for complete polymerization of the adhesive. If you do everything right, your Xiaomi Mi 9 will again be happy with the performance and appearance, and you will save a significant amount of money on the services of the service center.
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Quality assembly depends not only on the correctness of actions, but also on the cleanliness inside the case and the accuracy of applying adhesive compositions.