How to change the screen Xiaomi Mi 9T: full guide

Smartphone Xiaomi Mi 9T (It is also known as Redmi in the global market. K20) He's famous for his flawless design with a retractable camera and no cutouts on the display, but it's the lack of bezels that makes his glass extremely vulnerable to falls. A broken screen is not only an aesthetic problem, it's also a risk of damage. AMOLED-matrix, which can lead to complete failure of the device or the appearance of black spots.

Replacing a display module at home requires precision, tools and an understanding of the design of the device. Unlike budget models, it uses On-Cell technology, where the sensor and matrix are soldered into a single unit, which complicates the repair process, but simplifies the replacement process itself - you will have to change the entire module assembly.

Before you start disassembling, it is important to assess the extent of the damage, if the touch-kang works but the glass is broken or the image is completely lost, in both cases you will need to buy a new display module. Self-repair will save a significant amount compared to the services of the service center, but you will need patience and accuracy of movements.

Diagnosis and selection of components

The first step is to make a proper diagnosis, and users often confuse damage to the outer glass with a failure of the matrix, and if the screen shows ink stains, stripes, or it's completely black, but the phone is showing signs of life (vibration, sound), then the display itself is damaged.

When choosing a part for Xiaomi Mi 9T is critical to focus on quality.The market offers a variety of options, from cheap copies to originals. Cheap counterparts often have poor color reproduction, low brightness and can work incorrectly with the fingerprint scanner built into the screen.

• 💎 Original (Service Pack): comes in factory packaging, has perfect color reproduction and frame thickness.
• 📦 High-quality copy (OLED): visually almost does not differ, but may yield in brightness and viewing angles.
• 📉 Budget copy (LCD/IPS): much thicker than the original, requires a replacement frame, has low resolution and poor touch response.

Note the markings when you buy. For the Mi 9T, modules labeled EAA8015CN or similar codes depending on the matrix manufacturer (Samsung, Tianma) are suitable. Installing an inappropriate module can lead to a broken fingerprint scanner.

Tools and training required

The success of the operation depends on 80% on the preparation of the workplace and the availability of the right tools: you will need a smartphone repair kit that can be purchased from any electronics store or online. Do not try to use kitchen knives or sewing needles - this is guaranteed to damage the internal components.

The main tool for opening the case will be a hair dryer or thermal film (separator). the back cover of the Xiaomi Mi 9T is glued to a powerful double-sided tape, and without preheating, it is almost impossible to open the phone without damage.

Also, be sure to prepare the screw tank so as not to lose their different caliber instances. During the disassembly, it is better to photograph each stage so that during the assembly there are no questions about where this or that metal plate was attached.

The process of disassembling the smartphone

Start by removing the tray for SIM-This is a must, because trying to remove the back cover with the tray installed will cause it to break, and after removing the tray, you need to warm up the perimeter of the back cover.

⚠️ Warning: Don't heat the central part of the smartphone where the battery is located! 60-70 The degree can cause the battery to bloat or even fire. 2-3 minute.

After heating, gently insert the suction cup into the bottom of the back cover and make a small gap. Enter a plastic card or spatula into the resulting gap and guide it along the faces, cutting the adhesive layer. Move slowly, without making sharp jerks, so as not to damage the fingerprint scanner plume that can be attached to the cover.

When you remove the back cover, you get access to the insides. First of all, you turn off the battery, find the battery connector, and then you gently disconnect it with a plastic blade, and then you can unscrew the screws that hold the protective bar in the center of the case.

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Use a magnetic mat or a piece of paper with sectors drawn to arrange the screws in order of twisting them. Rotors of different lengths, and if you confuse their places when you build them, you can damage the motherboard.

Dismantling the old display

When the central protective plate is removed, we have access to the display and touchscreen plumes. In the Xiaomi Mi 9T, they are connected to the motherboard next to us.

Then comes the most difficult step, which is to remove the broken screen, which is also glued around the perimeter to the frame, and again we use a hair dryer to heat the front part (do not overheat the matrix, if it is still intact, warm moderately).

Pay special attention to the top end, where the plume of the retractable chamber is located, which is very easy to damage or tear if you don't cleanly dismantle it. If the screen doesn't lend itself, add a little more heat, but don't use excessive force.

After removing the module, you need to carefully clean the frame of the residue of old glue, for this, an alcohol or a special liquid is ideal. The surface must be perfectly smooth, otherwise the new screen will lie unevenly, and there may be lights or gaps.

Installation of a new module and assembly

Before you stick a new screen, you need to do a test connection, connect the new display plumes to the motherboard without fixing it in the frame, turn on the phone and check the matrix for broken pixels, the touchscreen throughout the area and, critically for the Mi 9T, the work of the fingerprint scanner.

If the test is successful, apply a new glue (B-7000 or special adhesive tapes) to the fat-free frame, evenly distribute the adhesive in a thin layer, install the display, slightly press it around the edges, and hold it with gums or a load for 15-20 minutes before the initial grasp.

Then the assembly process goes in reverse: set the metal bar, twist the screws, plug the battery in, check the phone again before the final sticking of the back cover.

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Quality cleaning of the frame from old glue is a guarantee that the new screen will lie flat and the smartphone will retain moisture protection (at least basic from dust).

Frequent errors and troubleshooting

When self-repairing, beginners often make a number of common mistakes, one of the most common being the damage to the plume of the underscreen scanner when you unplug an old battery or screen, which is very thin and fragile.

Another problem is the dust under the new glass, and if you're doing a replacement in a dusty room, small villi can get between the matrix and the touchscreen, which you'll notice when you have a white background on, and you can work in a clean room, you can even slightly moisten the air.

• 🔨 Twisted screws: can burst plastic mounting elements or damage the motherboard.
• 💥 Battery bloating: occurs when sloppy heating or mechanical damage to the battery by a blade.
• 🔌 Unpressed connectors: lead to unstable screen operation or its complete shutdown.

⚠️ Warning: If the phone doesn't turn on after assembly, don't panic. Check if the battery is connected. Sometimes the battery connector doesn't get up the first time. Also make sure the central plate screws are swirled – some phone models won’t turn on unless the proximity sensors or other contacts on the board are pinned with a bar.

Cost and feasibility of repair

The financial side of the matter is also important: At the time of writing, the cost of a quality display module for the Xiaomi Mi 9T varies depending on the exchange rate and region. Original parts are expensive, often accounting for a significant portion of the market price of a used phone.

If you plan to sell the device after repair, it makes sense to only put the original or high-quality copy (OLED). Cheap IPS-matrixes will immediately give out the fact of repair and significantly reduce the liquidity of the gadget. For personal use for several years, you can consider options for the middle price segment.

In conclusion, replacing the screen with Xiaomi Mi 9T is a medium-sized task that is available to a person with straight hands and a minimal set of tools, the main thing is to take your time, carefully monitor the plumes and use quality components.

FAQ: Frequently Asked Questions