Replacement of the keyboard with Xiaomi Mi 9T: disassembly, installation and adjustment

Keyboard on the smartphone Xiaomi Mi 9T (also known as the Redmi K20) — It's not just a way to type, but it's also a key part of how you interact with a device, and if it's no longer responsive to touch, stuck, displays incorrect characters, or is physically damaged, the only solution is often to replace it. However, many users are afraid to take up repairs on their own, fearing damage to fragile components or lose warranty.

In fact, the keyboard replacement (more precisely, the touchscreen display module, since Mi is the keyboard). 9T It's a complex procedure that requires precision and the right tools, and in this article, we'll look at how to diagnose a problem, pick up parts, and make a replacement without risking the device. And if we are talking about a physical keyboard (for example, in the case of using external accessories), then we will consider this option.

It is worth noting that Xiaomi Mi 9T It doesn't have a removable keyboard in the traditional sense -- all buttons are virtual. So "keyboard replacement" is more often meant to mean touchscreen repair or software reinstallation. We'll cover both scenarios, and we'll also talk about how to connect an external keyboard via Bluetooth or OTG, If the virtual system has stopped working.

1. Diagnosis of the problem: keyboard or touchscreen?

Before you start repairing, it's important to understand what exactly went wrong. - Xiaomi Mi 9T the keyboard is displayed on the screen, so input problems may be related to:

• 🔧 Software failure – for example, after an update MIUI or installing third-party software.
• 📱 Touchscreen malfunction – if the screen does not respond to touch or reacts incorrectly.
• 🔋 Hardware damage - falling, getting moisture, wear of the display plume.

To check if the keyboard or the screen itself is to blame, follow the following steps:

1. Go to Settings. → System system → Language and input → Virtual keyboard and select another keyboard (like Gboard.
2. Connect an external keyboard via Bluetooth or OTG-If it's working normally, the touchscreen is defective.
3. Check the screen response in Test Mode: dial ##6484## and follow the instructions on the screen.

If the screen does not respond to touch at all or displays “ghost” presses, you will most likely need to replace the display module (along with the touchscreen).

Preparation for replacement: tools and spare parts

If the diagnosis showed that the problem is in the touchscreen or display module, prepare the following:

• 🛠️ Set of screwdrivers (cross, flat, torks) T3 and T5 Xiaomi).
• 🔥 Hair dryer or thermal air station for softening glue (temperature 60-80)°C).
• 📏 Plastic mediators or shoulder blades for screen separation.
• 🧲 Suction cups to remove the display (optional, but simplifies the process).
• 🔌 New display module (with touchscreen) for Xiaomi Mi 9T (articular: DM-MI9T-XX, where XX — version).
• 🔋 Battery: If you plan to replace it at the same time).

⚠️ Warning: Buy a display module only from trusted sellers! Cheap Chinese counterparts often have issues with color rendering, touchscreen sensitivity or compatibility with the display. MIUI. Original parts are labeled as Original OEM.

Also prepare the workplace:

• 🪑 Clean table with good lighting.
• 🧹 Antistatic mat or substrate (so as not to damage the motherboard with static electricity).
• 📦 Containers for screws (so as not to confuse them during assembly).

3.The step-by-step dismantling of Xiaomi Mi 9T

Disassembly of Mi 9T It requires caution, because the body is glued together and the plumes are fragile:

Step 1: Removing the back cover

1. Turn off the phone and remove the tray for SIM-map.
2. Heat the edge of the back cover with a hair dryer (do not direct airflow to the camera or battery!).
3. Insert a plastic mediator into the gap between the lid and the case and gently dent it.
4. Walk the mediator around the perimeter, separating the glue. The lid should come away with a characteristic click.

Step 2: Shutting off the battery

1. Unscrew 10 screws that fix the metal plate over the battery (use a screwdriver). T3).
2. Carefully slap the plate and put it aside.
3. Unplug the battery plume with a plastic blade (do not use metal tools!).

Step 3: Removal of the display module

1. Unscrew the screws that hold the metal frame of the display.
2. Heat the edge of the screen with a hair dryer (no higher than 70).°C!) and gently suction or mediator it.
3. Disconnect the display and touchscreen plumes from the motherboard (theymarked as LCD Touch).

⚠️ Attention: Trail of the touchscreen on the Mi 9T Don't pull or bend it, it can cause the contacts to break, and if the plume is damaged, it will have to be replaced: Flex-Cable-MI9T-Touch).

At this point, you can replace the display module with a new one. Make sure all the plumes are tightly connected, but without effort.

1. Correctness of connection of the plumes (they must "click" when fixing).

2. Integrity of contacts on the motherboard (possibly oxidation).

3. compatibility of the new display with the firmware version (sometimes you need to update) MIUI).-->

Installation of a new display module

The process of installing a new screen is reversed disassembly, but there are several nuances:

• 🔄 Check compatibility - some displays for Mi 9T You may not support Always-On Display or have other limitations.
• 🧹 Clean contacts on motherboard and plumes with alcohol and cotton swab.
• 🔥 Use a new glue to fix the screen (for example, B-7000 double-sided 3M).

Procedure:

1. Connect the new display plumes to the motherboard (first Touch, then Touch). LCD).
2. Make sure the screen is exactly in the grooves of the body.
3. Apply the glue around the perimeter and gently press the display, avoiding bubbles.
4. Turn the metal frame screws (do not pull!).
5. Connect the battery and check the screen before final assembly.

If the screen is working after the replacement, but the keyboard is still not displayed, it may be a problem in the firmware, in which case resetting the settings or flashing through Fastboot will help.

5. Alternative solutions: external keyboard and software fixes

If replacing the display seems too difficult or expensive, consider alternatives:

1. Connecting an external keyboard

• 🔌 Bluetooth: Connect the keyboard to Settings → Bluetooth and select it as your input device.
• 🔌 Po Po Po OTG: Use the adapter. USB-C → USB-A And plug in the wired keyboard.

2. Software recovery methods

• 🔄 Resetting the keyboard: Go to Settings → Annexes → Application management → Keyboard and clear the cache.
• 🔄 Installing an alternative keyboard: Download Gboard or SwiftKey from Google Play.
• 🔄 Update MIUI: Check for updates in Settings → The phone. → Updating the system.

3. Use of voice input

If the screen is partially responsive, activate voice input:

1. Open any text field and click on the microphone icon on the keyboard.
2. Or turn on Google Assistant and use voice commands.

💡

If the problem is the touchscreen, not the keyboard, replacing the display module is the only reliable way to repair it, and external keyboards and software fixes will only help temporarily.

6. Frequent mistakes and how to avoid them

When replacing the keyboard (or display) with Xiaomi Mi 9T Users often make mistakes:

• 🔥 Overheating the screen with a hair dryer can damage the matrix or battery. Optimal temperature: 60-70°C.
• 🔧 Using inappropriate tools – metal blades scratch the body, and too thick mediators break the latches.
• 🔌 Incorrect connection of plumes - if you confuse LCD And Touch, the screen won't work.
• 🧹 The entry of dust under the screen - this leads to the appearance of spots or uneven illumination.

⚠️ Attention: On Xiaomi Mi 9T The touchscreen and display plume are only combined in some versions (for example, for the European market). In the Chinese version, they can be separated!

How to avoid problems:

• Use an antistatic bracelet or touch a grounded object regularly.
• Before turning off the plumes, take a picture of their location.
• Do not turn on the phone without a connected battery – it can burn the motherboard.

7 Post-replacement testing

After assembly of the device, it is necessary to check:

• 📱 Touch Screen Reaction – Test all screen areas (for example, using the Touch Screen Test app).
• 🎨 Color rendering – compare with another device to make sure there are no yellow or broken pixels.
• 🔋 The work of sensors - check autoturn, brightness, approach.
• 🔊 Sound and vibration – sometimes after disassembly, speakers or vibrator depart.

If the keyboard is still not working:

1. Check the language and input settings (Settings) → Additionally. → Language and input).
2. Update MIUI to the latest version.
3. Perform a reset settings (Settings → About Phone → Reset settings).

If the screen does not respond to touch:

• Check the density of the plumes.
• Make sure the new display is compatible with your Mi version. 9T (For example, global or Chinese).
• Contact the service center - the motherboard may be damaged.

FAQ: Frequent questions about replacing the keyboard with Xiaomi Mi 9T