Xiaomi Redmi: Why it appears and how to remove forever

You turned on the Xiaomi Redmi smartphone and found a mysterious semicircle on the screen that does not disappear when you reboot? POCO And Redmi K. The semicircle can be subtle or pronounced, interfere with the sensor, or just spoil the appearance of the display. 90 percent of the time, the cause is software, but sometimes the fault is iron.

In this article, we will analyze all possible sources of the problem - from a malfunction in the work. AMOLED-matrices before firmware errors MIUI. You will learn how to diagnose a malfunction, which settings to check first, and when to really carry the phone to the service. We also collected unique ways to eliminate a semicircle that you will not find in standard instructions, for example, resetting a cache via fastboot or calibrating the sensor in the engineering menu.

Important: If a semicircle appears after a fall or moisture, immediately go to the section on hardware damage. In all other cases, start with software methods - they are free and take no more than 10 minutes.

1.Diagnostics: Why a semicircle appeared on the Redmi screen

Before you try to remove a defect, you need to understand its nature.

• 🔄 Software artifact - a failure in the work of the graphic driver or MIUI (more frequently).
• 📱 Hardware defect of the matrix - damage to the backlight or screen layers (typically after impacts).
• 👆 The problem of the sensory layer is when a semicircle responds to touch or appears when pressed.
• ⚡ Next to oxidation – if the phone has come into contact with moisture (even without visible signs of water ingress).

How to distinguish a software problem from a hardware problem?

If you have one item on the left column that fits your situation, start with the software methods. If all the signs indicate a hardware malfunction, go to the repair section.

2. Software methods to remove a semicircle (without disassembly)

Start with the simplest methods – they help in 70% of cases.

Restarting in safe mode

Safe mode disables all third-party applications, which helps to identify the conflict of programs:

1. Press the power button before the off menu appears.
2. Press and hold the item "Switch off (or turn off power)."
3. Confirm the transition to safe mode.

If the semicircle is gone, one of the installed applications is to blame: delete the last installed programs or perform a cache reset (section 2.3).

Resetting screen settings

Sometimes the display settings fail, and you can bring them back to the factory settings like this:

1. Go to Settings → Display.
2. Slip on three points in the upper right corner → Reset settings.
3. Confirm the action.

After reset, check if the semicircle has disappeared. If not, proceed to the next method.

Clearing the system cache and Dalvik

Clogged cache can cause graphic artifacts. Clean it through the Recovery:

Turn off the phone.

Hold the Loud up. + Power before vibration

Select the language (volume buttons)

Choose Wipe & Reset → Wipe Cache

Confirm the cleanup.

Reset the device-->

If after cleaning the cache, a semicircle remains, try resetting the Dalvik cache (requires). TWRP):

1. Go to TWRP (clamping Volume Up + Nutrition).


2. Go to Advanced → Wipe Dalvik Cache.




3. Swipe for confirmation.




4.Reboot.

💡

If you don't. TWRP, but there is root access, clear Dalvik through the app SD Maid or Su Command -c "rm -r /data/dalvik-cache/*" terminally.

Update or rollback MIUI

A semicircle often appears after a firmware update.

• 🔄 Reverse to the previous version MIUI via fastboot (instructions in section 4).
• 🆙 Upgrade to the latest stable version (if the semicircle appears on beta firmware).
• 🛠️ Install custom firmware (e.g. Pixel Experience) if the problem is stock bugs MIUI.

Before firmware, make a data backup via Settings → The phone. → Backup.

Sensor calibration and matrix check

If a semicircle responds to touch or appears when you press the screen, the problem may be in the touch layer.

Calibration through the engineering menu

Enter the code in the phone application:

##6484##

On the menu that opens:

1. Select the Touch Screen Test.
2. Take the touch test – if the screen is not responding correctly, tap Calibration.
3. Follow the instructions on the screen (usually click on the crosses in the corners).

3.2. Checking the matrix for broken pixels

Run the display test:

1. Install Screen Test from Google Play.
2. Select the color gradients and black screen tests.
3. If a semicircle is visible on a black background, it is a matrix defect (repair is needed).

Resetting sensor settings

If the calibration does not help, reset the sensor settings through ADB:

adb shell settings delete global touchscreen_calibration_file


adb reboot

After restarting, the sensor is recalibrated automatically.

Hardware causes and repairs

If the software methods didn't work, the problem is the hardware.

Damage to the display plume

Symptoms:

• 🔌 A semicircle appears when you press a certain area of the screen.
• 📉 The brightness in the semicircle zone changes when the phone is bent.
• 🔄 The defect disappears if you slightly press on the body from the back side.

Solution: Replacement of the plume (cost) is required 1-3 thousand. + The temporary solution is to fix the case with scotch tape to reduce backlash.

Oxidation of contacts after moisture

Even if the phone didn't sink, moisture could get through the microphone or the speaker.

• 💧 The semicircle appeared after the rain / bath / pool.
• 🔋 The phone is quickly discharged or overheated.
• 🎧 The sound in the speakers is distorted.

Decision:

1. Turn off the phone immediately and remove it. SIM-map.
2. Place the device in a silica gel package on 24-48 hours.
3. If the semicircle remains - you need to clean the fee in the service (2-5 thousand.).

💡

Never dry your phone with a hair dryer or on a battery! this will speed up the oxidation of the contacts and can disable the power controller.

Defect: 4.3 AMOLED-matrix

If a semicircle:

• 🌈 Has rainbow divorces.
• ☀️ It's only visible from a certain angle.
• 📱 Appeared for no apparent reason and does not disappear.

Repair is possible only by replacing the screen (from 4 thousand rubles for the Redmi Note to 15 thousand rubles for the Redmi K series).

⚠️ Warning: Don't buy cheap Chinese matrices on AliExpress! 80% of the time they have the worst color reproduction and burn out faster. Original parts can be found from official Xiaomi suppliers or in trusted services.

5. Firmware through Fastboot (advanced method)

If the semicircle appeared after the update MIUI And it doesn't disappear, and it's going to help with clean firmware through fastboot, and this method deletes all the data, so you can do a backup beforehand!

Preparation

You'll need:

• 🖥️ Computer with Windows/Linux.
• 🔌 Cable USB Type-C (original!).
• 📁 Firmware for your model (download from the official Xiaomi website).
• 🛠️ Mi Flash Tool (version 2023 or later).

Step-by-step instructions

1. Unpack the firmware in a folder without Cyrillic characters (for example, C:\ROM\redmi_note11).
2. Turn off the phone and press Volume Down + Power to log in to fastboot.
3. Connect your phone to your PC and start the Mi Flash Tool.
4. Click Select and point the way to the firmware folder.
5. Select Clean All (Full Cleaning) mode.
6. Press Flash and wait until it is completed (10-15 minutes).

Once the firmware is in place, the phone will restart, and if the semicircle is gone, the problem was the corrupted system files.

⚠️ Warning: Don't interrupt the firmware process! This can cause the phone to be bricked. If the firmware has been frozen 99% longer than 10 minutes, turn off the phone, press the Loudness up. + Eat for 20 seconds and repeat the process.

6. Alternative solutions (if nothing has worked)

If all methods have been tried, but the semicircle remains, try:

Disconnection of hardware acceleration

Sometimes graphic artifacts are caused by rendering failures.

1. Activate Developer Mode (7 times tap the MIUI version in Settings → About Phone).
2. Go to Settings. → Additionally. → For developers.
3. Find options: Disable hardware acceleration (if any). GPU-rendering → Enforcement of use GPU → turn off.

Reboot the phone.

6.2 Use of Live Wallpaper for disguise

If the semicircle does not interfere with the work, but spoils the view, mask it:

• 🎨 Install animated wallpaper (for example, 3D Parallax Background).
• 🖼️ Choose wallpaper with a gradient or abstract pattern that visually “merges” with the defect.
• 🔍 In the wallpaper settings, reduce the brightness in the semicircle zone.

6.3 Feedback in Xiaomi

If the defect appears on a new phone (up to 14 days after purchase) or after an official update, please contact us for support:

• 📧 Write to service.ru@xiaomi.com screenshot and check.
• 📞 Call 8 800 700 05 65 (free in Russia).
• 🏬 Find the nearest authorized service.

Under the Consumer Protection Act, you are entitled to free repairs or replacements if the defect is not caused by mechanical damage.

FAQ: Frequent questions about the semicircle on the Redmi screen