How to disassemble Xiaomi Mi 9T: step-by-step instructions for pros

The Xiaomi Mi 9T, known globally as the Redmi K20, has been a hit with its bezel-less design and outgoing front camera. However, this design feature imprints on the complexity of the internal device, making the disassembly process more time-consuming than standard smartphones that have cutouts or holes in the display. Owners planning to replace a broken screen or a bloated battery need to clearly understand the sequence of actions so as not to damage fragile mechanisms.

The main challenge is that the back cover is not a separate element, but a single frame with a display, which requires special care when heating and opening. Any careless movement can damage the camera motor plume or the main display plume, which is a significant part of the price of the device, which is why it is critical to prepare the workplace and the necessary tools before starting work.

In this article, we will take a detailed look at each stage of dismantling, paying attention to hidden screws and thin plumes that are easy to break. You will learn how to safely turn off the battery and not damage the image stabilization system in the main camera. A deep understanding of the internal architecture of the Redmi K20 / Mi 9T will allow you to perform repairs with quality and avoid common beginner errors.

Preparation of the workplace and necessary tools

Before you start physically affecting the body of your smartphone, you need to organize space. The ideal option would be an antistatic mat that protects electronics from static electricity, especially in dry rooms. Lack of static is the first step to successful repair, because chips in modern devices are extremely sensitive to discharges.

You will need a specialized set of tools without which safe disassembly is impossible. The use of improvised tools such as knives or thick needles is strongly discouraged, as they can damage internal partitions or punctur the battery.

• 🔧 Hair dryer or thermoplatform for uniform heating of the glue around the perimeter of the housing.
• 💳 Plastic cards or special mediators (spudger) for opening the case without scratches.
• 🌀 A set of Torx screwdrivers (stars) sizes T2, T3 and T5 screw-on.
• 🧲 Magnetic mat or organizer for sorting screws of different sizes.

Special attention should be paid to the suction cup, which will help create the initial gap between the frame and the display. If there is no suction cup, you can use a thin metal blade, but you need to act with extreme caution not to break the glass. Also prepare isopropyl alcohol in advance, which will help dissolve the old glue when reassembled.

Initial opening of the body and dismantling of the rear panel

The process begins with the removal of the tray for SIM-This is the standard procedure for most Xiaomi smartphones, and then you have to flip the screen down and evenly warm the perimeter of the back cover. 80-90 degrees Celsius, so as not to damage the oleophobic coating of the display on the front side or not to deform the plastic frame.

⚠️ Warning: Do not heat the central part of the back too intensely, as there is a battery under it, heating which can lead to fire or bloating.

After warming up for 2-3 minutes, gently insert the suction cup at the bottom of the back cover and pull up while simultaneously injecting the plastic card into the resulting gap. Move the map around the perimeter, cutting through the adhesive layer, but avoid deep penetration into the top where the camera mechanism is located.The adhesive layer in this model is quite powerful, and it takes patience to separate the panel without chipping.

Once the panel is free of the glue, don't try to remove it completely right away. Inside, there may be thin plumes connecting buttons or antenna modules, although in the Mi 9T, the main communication goes through the connectors on the board. Carefully lift the cover and make sure there are no connections before the final removal.

Removal of the protective plate and disconnection of the battery

When you take the back cover off, you'll see a black protective plate covering the motherboard and the battery, and it's locked in a lot of different size screws that need to be twisted in sequence, and most commonly, the Torx T4 and T5 screws are easily confused, so sort them out as you unscrew them.

The first thing you do when you open the circuit board is to turn off the battery connector. It's the golden rule of mobile repair: shutting down the device before you manipulate the plumes of the display or the cameras prevents you from shorting. Use a plastic blade to tamper with the connector chips, avoiding metal objects.

Once the battery is turned off, you can safely remove the metal plate, underneath which are the main connectors of the display, touch screen and cameras. Beware: some screws may be hidden under stickers or seals, their violation may indicate a previous opening of the device.

Working with the camera and its mechanism

The Xiaomi Mi 9T’s unique feature is a motorized front camera, which requires careful handling to remove or replace the mechanism, and is mounted on a separate module and connected with a thin plume that can be easily damaged if handled carelessly.

First, disconnect the engine plume from the motherboard. Then unscrew the screws that hold the camera block itself. When you remove the module, watch the guides that the camera is driving on, and if dust or small debris gets into them, the mechanism can jam, and the camera will stop moving or will do it with errors.

• 📸 Carefully disconnect the plume without pulling it sharply to the side.
• 🔩 Unscrew the screws of the mechanism fastening, remembering their location.
• 🧹 Blow the compartment with compressed air before installing the new module.

If you are changing the camera, make sure that the new sensor is compatible with your device’s firmware version, and in some cases, after the replacement, you need to calibrate through an engineering menu or special software, otherwise the photos may be blurred or with artifacts.

💡

When installing the camera mechanism, apply a minimum amount of lubrication to the guides if they look dry, but avoid getting fat on the lenses or sensors.

Replacement of the display and neat work with plumes

The most important step is to replace the display. Unlike many other models, here the screen is glued into a frame, and replacing the glass or touchscreen separately at home is almost impossible without professional equipment.

To remove the old module, you need to turn off all the remaining plumes: the main display plume, the touchscreen plume and the side button plume (if it is not integrated), then the body is reheated to soften the glue that holds the matrix in the frame. Use the suction cup and mediators to separate the screen.

⚠️ Attention: AMOLED-matrices in Mi 9T Any pressure that you put your finger or tool into the center of the screen can cause black spots or cause the matrix to fail completely.

Install the new module by connecting the plumes. Make sure they snap to the characteristic click. Then apply a new glue (B-7000 or special glue for screens) around the perimeter of the frame and tightly press the display. Lock the device with rubber bands for 15-20 minutes before the initial grasp of the glue.

Assembly of the device and verification of functionality

The final stage of the repair is assembly, which is done in reverse order, but requires all systems to be checked before the final sealing of the case. Don't rush to twist all the screws at once, plug the battery in first and turn on the phone.

Check the touchscreen, the display response, the speakers, the microphone and, of course, the camera that's out, and if all the functions are working correctly, you can start to finalize the screws and stick a new moisture pad.

• 🔋 Connect the battery and turn on the device for the test.
• 📱 Check the multi-touch and sensor operation throughout the area.
• 🔊 Test the sound in the speaker and through headphones.

Make sure all screws are twisted but not pulled to avoid tearing the thread in the plastic bushings.A quality build ensures that the smartphone will last for a long time without backlashes and creaks.

💡

The main key to success is not to rush when disconnecting the plumes and carefully warm up the adhesive joints before each step of disassembly.

Frequently Asked Questions (FAQ)