How to check the touch screen on Xiaomi Redmi smartphones: from diagnosis to repair

Touch screen is one of the most vulnerable parts of the smartphone Xiaomi Redmi. Even after a slight drop or moisture touchscreen can start to fail: do not respond to touch, “swim” when entering, or refuse to work in separate areas. But before you carry the phone to the service center, you should check the performance of the sensor — perhaps the problem is solved programmatically or is a consequence of screen contamination.

In this article, we’ll look at 5 reliable diagnostic methods, including hidden Xiaomi service menus, third-party apps and hardware tests, how to identify dead zones, check touch sensitivity, and even determine whether the display itself or system software is to blame for the malfunction, and if the sensor is already dead, we’ll give you a checklist of actions to avoid exacerbating the problem before repair.

1. Quick sensor check without software

Before you get into the technical details, do a basic test to help weed out the obvious problems:

• 🧹 Clean the screen. Fat marks, dust or bubble protective film can block touch. Wipe the display with a microfiber wipe soaked in alcohol solution (at least 70%).
• 🔄 Restart your smartphone. The system freezes sometimes leads to "glitch" touch screen. Hold the power button 10-15 seconds until vibration.
• 👆 Check your response to touch. Swipe your finger all over the screen -- if the cursor jumps or disappears in certain places, it's a sign of hardware malfunction.
• 🔋 At a charge below 10%, some Redmi models artificially reduce sensor sensitivity.

If you've had a problem with this manipulation, you can go to a deep diagnostics, and you can focus on the areas around the edges of the screen, which is where sensors fail most often after falls.

⚠️ Note: Do not use paper wipes or rough fabrics to clean the screen - they scratch the oleophobic coating, which further worsens the slip of the finger and can simulate the "lag" of the sensor.

2. Xiaomi's built-in service menu (CIT)

All Xiaomi and Redmi smartphones have a hidden hardware component testing menu called the Component Identification Test (CIT), which allows you to check the sensor, display, speakers and other modules without installing third-party applications.

1. Open the Phone app.
2. Enter the combination: ##4636###.
3. In the menu that appears, select Testing (or Service tests on Russian firmware).
4. Slip on the Touch Screen Test item.

You'll see a grid of numbers on the screen, and your task is to alternately touch each sector, and if the number changes color after touching it (usually green), the sensor in that area is activated, and if you touch it, the red color or no response signals a malfunction.

Check the cleanness of the hands (fat / moisture interfere with touch)

Make sure there are no cracks or chips on the screen

Repeat the test after rebooting

Remove the case (it can press on the body and deform the sensor plume)-->

On some models (e.g. Redmi Note 10 Pro or POCO X3), the path to the test may be different.

Settings → About Phone → MIUI Version (stamp 5-7 times before the message “You became a developer”) → Return to “Additional” → For developers → Diagnostics → Sensor Test

⚠️ Attention: On firmware MIUI Over 12.5, the ##4636## combination may not work, in which case use the alternative method through the developer menu or install third-party utilities (for these, see the next section).

3. Third-party applications for sensor testing

If Xiaomi’s built-in tools aren’t available or don’t give you the full picture, use specialized utilities. They offer advanced tests, including multi-touch testing (simultaneously touching with multiple fingers) and sensitivity to taps.

Top.-3 diagnostics:

• 📱 Touch Screen Test (from KVADGroup) - shows touch coordinates, tests multi-touch up to 10 fingers, saves error log.
• 🔍 Sensor Test – checks not only the sensor, but also the gyroscope, accelerometer, compass (useful if the screen “floats” when cornering).
• 🛠️ Phone Doctor Plus – a comprehensive test of all components of the smartphone, including touchscreen, display and battery.

How to use (for example, Touch Screen Test):

1. Download the app from Google Play.
2. Run the Single Touch test, swipe across the screen to track the line, and breaks or jumps in the cursor will indicate problem areas.
3. Activate Multi Touch and touch the screen with 2-5 fingers. If some of the touches are not fixed, this may be a sign of damage to the plume.

💡

If the app shows reaction delays (lags) in all areas of the screen, try turning off the Sensitivity Increase feature in the MIUI settings: Settings → Special features → Physical features → Screen sensitivity. Sometimes this option conflicts with the sensor drivers.

Third-party utilities are also useful for comparing results before and after a repair, for example, if you have replaced the sensor but the screen has become less responsive, the tests will help document the problem for a warranty case.

4. Check the plume and sensor connection

If software tests show that the sensor is not responding at all or is partially working, the problem may lie in damage to the plume, the flexible cable connecting the touchscreen to the motherboard, a typical malfunction after falls or heavy presses on the screen.

How to check the plume without disassembling the phone:

• 🔊 Listen to the sounds. When you press the screen in the plume area (usually the bottom part), you can hear a slight crackling, which is a signal of mechanical damage.

The visual inspection of the plume requires the removal of the smartphone. On the Redmi Note 8/9/10 and POCO F3 models, the sensor plume is located under the metal frame of the screen, which can be seen after removing the back cover and battery. If you are not sure of your skills, you better contact the service.

5. Hardware diagnostics: when replacement is needed

If all the tests show that the sensor is faulty and the software methods didn't work, there are two options: repair or replacement, and here are the criteria by which you can determine that the touchscreen requires physical intervention:

• 💥 Cracks on the screen, even if the sensor is still working, and microcracks will eventually cause complete failure.
• 🔴 Constant "ghost" touches (the screen presses the buttons itself) This is a sign of damage to the sensory matrix.
• 🔌 If the reset to the factory settings didn't help, the hardware problem was not.
• 📉 Deterioration over time: If the area of the non-working sensor expands, the plume or controller degrades.

The cost of repair depends on the model:

• Redmi 9A/10A: sensor-replacement — 2 500–4 000 ₽ (screen assembly is cheaper than a separate touchscreen).
• Redmi Note 11/12 Pro: 5 000–8 000 ₽ due to the complexity of disassembly (glued screen).
• POCO F4/F5: 6 000–10 000 ₽ (AMOLED-displays are more expensive in repair).

Before you carry your phone to the service, check the warranty status:

1. Go to mi.com/global/verify.
2. Enter your Redmi’s IMEI (you can find it in Settings → About Phone → General Information).
3. If the warranty is valid, repairs can be free (provided the damage is not mechanical).

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Don't settle for a touch-only replacement if the wizard suggests putting the screen assembled. On Redmi models older than 2020, the touchscreen and display are glued together, and separate repairs often result in air bubbles or uneven backlighting.

6. Frequent errors in diagnosis and how to avoid them

Many users are making sensor problems worse because of wrong actions.-5 Mistakes and how to prevent them:

• 🔨 Disassembly without tools, using a knife or screwdriver instead of a plastic shoulder blade causes scratches on the body or damage to the plumes.
• 💦 Liquids leaking from cleaning, alcohol or moisture leaking under the screen can cause contacts to corrosion.
• ⚡ Ignoring battery discharge: At a charge level below 20%, some tests (e.g, CIT) They can give false positives.
• 📱 Installation of informal firmware. MIUI-Ports often contain bugs in sensor drivers.
• 🛒 Buying cheap parts, sensors from unknown manufacturers may have low sensitivity or incorrect calibration.

If you decide to repair your phone yourself, follow the rules:

1. Work on an antistatic mat – static electricity kills the chips.
2. Use a hair dryer or thermoplatform to unplug the screen – do not try to force it.
3. Before assembly, blow the body with compressed air - the dust under the Later screen can cause the "moir effect".

Self-cleaning/resetting

I use the Xiaomi service menu.

Installation of applications for tests

Take me to the service center.

Changing my phone.-->

FAQ: Answers to Frequent Questions