Touchscreen on the phone Xiaomi Redmi: the principle of operation, diagnostics of malfunctions and repair methods

Have you ever wondered how your Xiaomi Redmi recognizes touchscreen? That's the touchscreen, the thin transparent layer that converts finger touches into commands for the system. Without it, your smartphone becomes a useless brick: you have a picture on the display, but you can't interact with it. In this article, we'll look at what a touchscreen is, how it works in Redmi models, why it stops working, and what to do if the sensor refuses to respond to touch.

Touchscreen issues are one of the most common malfunctions in Xiaomi smartphones. Service centers estimate that up to 30 percent of the calls are due to a touchscreen malfunction, and the causes range from mechanical damage to software failures, and we'll tell you how to diagnose a breakdown yourself, when you can do without repair, and when you have to carry your phone to the workshop, and you'll also learn which Redmi models are most likely to suffer from touchscreen glitches and how to prolong the life of the screen.

What is a touchscreen and how it works in Xiaomi Redmi smartphones

Touchscreen is a transparent panel placed on top of a display that registers touch. Today's Xiaomi Redmi smartphones use two types of technology:

• 🔹 Capacitive touchscreens are the most common, and they work by changing the electrostatic field when you touch your finger. They're used in every Redmi since the Redmi Note 3.
• 🔹 Resistive touchscreens are an outdated type that responds to pressure, only found in very old or budget models (e.g. Redmi). 1S).

In smartphones Xiaomi touchscreen is usually a multi-layer structure:

1. Protective glass (often with an oleophobic coating).
2. The sensor layer (conducting electrodes).
3. The glue layer (OCA-film) connecting the touchscreen to the display.
4. Screen Matrix (AMOLED or IPS)

When you touch the screen, the touchscreen controller captures the change in signal at the touchpoint and transmits the coordinates to the processor. Multitouch-enabled Redmi models use an electrode matrix that scans the screen at up to 240 Hz, which ensures smooth response.

Signs of a faulty touchscreen on Xiaomi Redmi

There are a few common symptoms that tell you something's wrong with the touchscreen, and it's important to distinguish hardware breakdowns from software failures, which will save you money on unnecessary repairs.

• 📵 The screen doesn't respond to touch, which is the most obvious manifestation, and the display can work (the image is there), but the touches are not recorded.
• 🎯 «Floating taps — the sensor activates on its own or registers touches elsewhere, often after a phone falls.
• ⚡ Hanging and braking: delayed response to touch (more than 0.5 seconds) may be due to overheating or wear of the plume.
• 🔄 Part of the screen is not working, such as the top or bottom area, not responding, typical for models with flexible plumes (Redmi Note 8 Pro, Redmi). 9T).
• 🌡️ Works only when heated/cooled - a sign of poor plume contact or contact oxidation.

If the sensor stops working after the update MIUI, Hardware malfunctions usually occur after mechanical stresses: falls, bumps, moisture. AMOLED-screens (e.g. Redmi) K40, Redmi Note 10 Pro touchscreen often fails due to deformation of the metal frame under strong compression.

💡

Before carrying the phone for repair, try connecting it to your computer and checking the sensor through ADB. If input tap and input swipe commands are executed, the problem is most likely in the firmware, not in the hardware.

Why the touchscreen on Xiaomi Redmi breaks down: top-5 cause

Analysis of service center data shows that 70% of the touchscreen failures on Xiaomi Redmi are due to mechanical damage, but there are other reasons that users often do not know.

Especially vulnerable are plastic models (such as Redmi 9A or Redmi 8A) when the impact is transmitted directly to the screen, while in smartphones with a metal frame (Redmi Note 10 Pro) the energy is partially extinguished, and in the risk zone of a device with a protruding camera – when falling on the back, the screen often cracks due to uneven load distribution.

⚠️ WARNING: If the touchscreen works after the fall, but there are "web spiders" or white spots on the screen, do not postpone repairs! Microcracks in the touch layer over time lead to complete failure of the touchscreen due to corrosion of conductors.

How to check the touchscreen on your own Xiaomi Redmi

Before you bring your phone to the service, you can do a diagnostic at home, which will help you understand if the problem is in the touchscreen, display or firmware.

The easiest way is to test the sensor through the engineering menu:

1. Open the Phone app.
2. Enter the combination: ##6484## (for some models ##284##).
3. Select Touch Test or Sensor Test.
4. Swipe your finger across the screen, there should be colored footprints, and if there are gaps or "extra" points, the touchscreen is faulty.

If the engineering menu is not available, use third-party apps, such as the Touch Screen Test from Google Play. Also check the sensor in safe mode (press the power button → Power off → Hold off until the suggestion to go to safe mode appears). If this mode touch screen works normally, the problem is in the installed applications.

What to do if the touchscreen on Xiaomi Redmi does not work

The algorithm of the actions depends on the cause of the failure. Let's look at the options from the simplest to the most complex.

1. Programmatic failures

• 🔄 Reboot – Sometimes a normal reboot helps, especially if the sensor is “hang” after the update.
• 📱 Resetting settings - go to Settings → The phone. → Reset settings.Be sure to back up your Mi Cloud or computer before resetting - after the procedure, all data will be deleted.
• 🖥️ Fastboot firmware – if the phone doesn’t respond to touch, but turns on, you can flash it through your PC using the Mi Flash Tool.

Hardware malfunctions

If the software methods didn't work, you'll have to disassemble the phone. In most Redmi models, the touchscreen is glued to the display, so replacing it requires special equipment (glue lamps, suction cups, mediators).

⚠️ Note: In the Redmi Note models 8/9/10 The touchscreen plume runs under the battery, and if you replace it yourself, you can damage the battery or tear off the contacts, and if you don't have experience, you should contact the service.

The cost of replacing the touchscreen in the service center:

• 💰 Redmi 9A/9C — from 1 500 before 2 500 ruble.
• 💰 Redmi Note 10/11 — from 3 000 before 5 000 RUB (depending on the type of screen).
• 💰 Redmi K40/K50 — from 6 000 ^ "Due to the difficulty of disassembling).

💡

In 80% of cases, replacing the touchscreen with Xiaomi Redmi requires simultaneous replacement of the display, since they are glued together.Separate replacement of the touch layer is possible only in specialized workshops with lamination equipment.

How to extend the life of the touchscreen on Xiaomi Redmi: 7 tips

Compliance with simple rules will help to avoid breakdowns and save on repairs.

• 🛡️ Use a high-quality protective glass, which reduces the load on the touch layer when impacted. Redmi Note is suitable glass with a thickness of 0.33 mm and hardness. 9H.
• 🧴 Apply an oleophobic coating, which reduces the friction of the finger against the screen, reducing the wear of conductors. In Redmi models, the factory coating is erased in 6-12 months.
• 🔥 Avoid overheating – do not leave your phone in direct sunlight or play heavy games (such as Genshin Impact) without cooling.
• 💧 Protect from moisture – even if the model has protection IP53 (as Redmi Note 11), prolonged exposure to moisture leads to corrosion of the touchscreen contacts.
• 🔋 Do not discharge the battery to 0% - at a deep discharge, the touchscreen controller can reset the calibration.
• 📦 Store in a depreciation case - models with a protruding camera (Redmi) K50) Particularly vulnerable to falling on the back.
• 🧼 Clean the screen correctly - use a microfiber wipe and alcohol wipes (no more than 70% isopropyl alcohol.

In Redmi models with high sensor polling frequency (180-240 Hz, as in Redmi K60), the touchscreen wears out faster due to increased load. If you do not play mobile shooters, you can reduce the polling frequency through the engineering menu (combination # #3644633# → Touch Panel Test → Touch Rate).

FAQ: Frequent questions about touchscreen on Xiaomi Redmi