Replacement of the bottom buttons on Xiaomi smartphones: from diagnosis to installation

The bottom buttons on Xiaomi smartphones are one of the most vulnerable parts of the device, and over time they start to fail, stick or completely stop responding to clicks. If you are faced with a home, back or recent button, do not rush to carry the phone to the service center. In most cases, you can replace them yourself, saving time and money.

In this article, we will discuss all the stages of the process: from fault diagnosis to installing new buttons. You will learn what tools you will need, how to disassemble the Xiaomi body without damage, and what nuances are important to consider when working with different models (from Redmi Note 4X to Mi 11).

Before you start replacing, make sure that the hardware is the problem. Sometimes the buttons are a software failure. Check it out simply by plugging your phone into your computer and trying to control it via ADB or enabling USB debugging in the developer settings. If the buttons don't respond in this mode, start repairing.

1. Types of lower buttons on Xiaomi: touch vs mechanical

Xiaomi smartphones use two types of bottom buttons, and the difficulty of replacing them depends on this:

• 🔘 Mechanical buttons are physical keys that are pressed with a characteristic click. 3S, Redmi 4A, Mi 5) Their replacement requires care, as they are attached to the board via microswitches.
• 📱 Touch buttons – integrated into the display or as a separate touchpad under the screen, used in 18:9 and 19:9 aspect ratio models (Redmi Note 7, Mi 9, POCO X3). Here more often fails not the button itself, but the plume or controller.

Mechanical buttons break down because of dust, moisture or wear of contacts. Touch buttons are more likely to suffer falls (the plume peels off) or factory defects. AMOLED-screens (e.g., Mi) 10T) Touch buttons can be part of the display module, and their replacement will require a complete disassembly of the screen.

How to determine the type of buttons on your Xiaomi?

• 🔍 Look at the bottom of the screen: if the buttons are drawn on glass, they are touch-sensitive.
• 🔊 Click on them: if you feel a physical stroke - mechanical.
• 📋 Check the characteristics of the model on the official Xiaomi website.

⚠️ Note: In some models (e.g. Redmi Note 8 Pro), the touch panel of the buttons is soldered to the motherboard, and trying to replace it without soldering equipment will lead to the phone inoperability.

2. Diagnostics of malfunction: software or hardware problem?

Before you disassemble the phone, make sure the buttons actually break physically.

1. Reboot. Sometimes buttons stop working after the MIUI update. Just restart the device.
2. Safe Mode. Press the power button, hold the power off until the request to go to Safe Mode appears, and if the buttons are running, the third-party app is to blame.
3. Sensor test. Type ##4636## in the dialer, select Equipment Test → Touch screen, and check your response to pressing.
4. If the input keyevent 3 (Home button) or input keyevent 4 (Back) are triggered through ADB, the hardware problem is.

If none of the methods worked, it is likely that the following are faulty:

• 🔌 Contacts or button plume (for mechanical applications).
• 🛠️ Microswitches on the motherboard.
• 📱 Touchbar or its controller (for virtual buttons).

3. Necessary tools and spare parts

To replace the buttons on Xiaomi, you will need:

When buying spare parts, pay attention to:

• 📌 The exact name of the model (for example, Redmi Note 7 has modifications) M1901F7G and M1901F7H — buttons may differ!).
• 🔍 Type of buttons (mechanical or touch-sensitive).
• ⭐ Seller Rating – Choose Verified Suppliers with Reviews.

⚠️ Attention: Cheap AliExpress buttons often go without a protective film.Put the tape on the back before installation to avoid short circuits.

4. Step-by-step instructions for replacing mechanical buttons

Consider the Redmi 4X process (similar to Redmi 3S/3X, Mi 5):

1. Remove the back cover. Carefully apply the lid with a plastic blade, starting at the corners. In Redmi 4X, it is held on the latches - do not apply excessive force so as not to break the mounts.
2. Unscrew the screws. Unscrew all the screws (usually 8-10 pieces) with a T4 screwdriver. Stack them in a separate box so you don't lose them.
3. Disconnect the battery plume. Use a plastic spatula to gently lift the battery connector. Don't pull the wires!
4. Dismant the motherboard. Unscrew the circuit board screws and unplug all the plumes (cameras, display, buttons) and the board is pulled at an angle, so don't rot it.
5. Replace buttons. Mechanical buttons are attached to small springs. Remove the old ones, install new ones, and check them before they're assembled.

The assembly is done in reverse order. After turning on the phone, check:

• 🔋 Battery operation (must be charged).
• 📶 Network signal and Wi-Fi.
• 🔊 Performance of speakers and microphone.

5. Replacement of touch buttons (on the example of Redmi Note 5)

Touch buttons are more difficult to replace because they are often integrated into the display module. In the Redmi Note 5, they are a separate flexible board under the screen.

1. Heat the screen. Dryer warm up the edges of the display (temperature ~60°C) for 2-3 minutes to soften the glue.
2. Separate the screen. With a suction cup, lift the display up and gently tuck it in with a plastic spatula. Don't lift the screen completely, it's connected by a plume!
3. Unplug the plumes. Unplug the metallic protection of the plumes and unplug them from the board. The plume of the touch buttons is usually next to the display connector.
4. Replace the touchpad. Carefully remove the old panel and install a new one. Make sure the contacts are not contaminated or oxidized.

When assembled:

• 🔧 Use a new two-way Scotch to lock the screen.
• 🧲 Check the sensor before final assembly.

⚠️ Attention: In models with AMOLED-The touch buttons can be part of the display module, replacing them will require the purchase of a new screen!

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If the touch buttons don’t work properly after replacing them (for example, they will work on their own), try calibrating them through the engineering menu. To do this, type ##3644633## and select Sensor Test.

6. Frequent mistakes and how to avoid them

Even experienced craftsmen sometimes make mistakes when replacing buttons.

• 🔧 Train damage. Never pull the wires, just the connectors! Use plastic-tipped tweezers.
• 🔥 Overheating board.When soldering, do not keep the soldering iron longer than 3 seconds on one contact.
• 💧 Getting moisture. Work in a dry room. If the buttons stick after you change, dry your phone in rice for 24 hours.
• 🔄 Wrong assembly. All screws must be twisted into their places - tangled mounts can damage the board.

If the buttons are not working after the change:

1. Check the integrity of the tracks on the board with a magnifying glass.
2. Test the new buttons with a multimeter (resistance should be ~0 Ohms when pressed).
3. Update the firmware – sometimes you need to flash the button drivers.

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If you're not sure about your soldering skills, you'd better contact the service. Damage to the motherboard when self-repaired can make the phone completely inoperable.

7. Alternative solutions: software button emulation

If you can not replace the buttons, you can use software alternatives:

• 📱 Virtual navigation bar. Included in Settings → System system → Gestures → Virtual buttons. Works on all models with MIUI 10 and newer.
• 🖱️ Gesture control. In the same settings, you can enable full-screen gestures (swipe from the bottom edge of the screen).
• 🤖 Emulator apps, such as Button Mapper or EasyTouch, allow you to reassign button functions to other gestures or virtual keys.

Cons of software solutions:

• ⚠️ Take up screen space.
• ⚠️ They may conflict with certain games.
• ⚠️ Increase battery consumption on 5-10%.

If you’ve chosen this option, remember to turn off virtual buttons when watching a full-screen video – they can get in the way.

FAQ: Frequent questions about replacing buttons with Xiaomi