Xiaomi’s Redmi Note 9 series is well-deservedly popular for its excellent price-to-quality ratio, but users often face intrusive proximity sensor work. A situation where the screen goes out and does not respond to touch during a conversation can lead to missed calls or an accidental call completion. This is a common problem associated with software calibration or design features of the device, when the sensor takes a protective film or finger for an obstacle.
It is important for owners of Redmi Note 9 to understand that complete hardware shutdown of the sensor is impossible without physical modification of the board, which will deprive of warranty. However, there are a number of software methods that allow you to ignore its readings or adjust the sensitivity of the system. In this article, we will discuss in detail how to configure the proximity sensor, use hidden engineering menus and third-party applications for comfortable operation of the phone.
Ignoring sensor readings is a temporary but effective solution for those who often use speakerphones or headsets.We will look at safe ways to adjust through the standard menu, as well as more advanced methods for power users, including working with the user interface. ADB-The right setup will allow you to forget about the black screen during important conversations.
Principle of operation and causes of sensor failures
The proximity sensor, or proximity sensor, is an infrared emitter and receiver located at the top of the smartphone body. Its main task is to determine the distance to the object, in this case, your ear, and turn off the display to save energy and prevent accidental cheekstrokes. In the Redmi Note 9 model, this component is often integrated into the speaker design, making it sensitive to contamination and miscalibration.
Failures can be caused by things ranging from banal dust to software conflicts. Often users notice that the screen goes out even when the phone is lying on the table or in the hand at a distance, indicating that the calibration is downed or the protective glass is overriding the sensor. It is important to distinguish between software errors and physical component failure.
⚠️ Note: If the screen goes out only when pressed tightly to the ear, but does not respond to light touch, perhaps the problem is not in the sensor, and in the work of the touch screen or protective film.
There are several main reasons why the sensor is not working properly on Xiaomi devices, and understanding the source of the problem will help you choose the right method to fix it, and you should not immediately resort to radical measures, such as flashing, without checking the basic settings.
- 📱 Protective film or glass: Incorrectly pasted protection often overlaps the infrared beam, causing a false positive.
- 🧹 Pollution: Dirt, fat, or dust in the upper speaker area blocks the sensor signal.
- 📲 Software bug: Errors in the shell MIUI This may lead to incorrect signal processing from the equipment.
- 🔋 Unstable voltage: In rare cases, voltage surges affect the operation of peripheral sensors.
Checking the serviceability through the engineering menu
Before you try to disable or configure the sensor, you need to make sure that it is physically healthy. The MIUI shell installed on the Redmi Note 9 has a hidden engineering menu for testing the equipment, accessed through a standard dialing interface, which does not require superuser rights.
To start the diagnosis, open the Phone app and enter a special code. This action activates the hidden CIT section, where you can check the operation of all modules. Find the "Proximity Sensor" item in the list and follow the instructions on the screen. You usually need to close the top of the phone with your hand and check if the value changes from 5.0 to 0.0.
##6484##If the test values do not change or the sensor shows a constant operation without overlap, this may indicate a hardware malfunction, in which case the software methods may not help, and you need to contact the service center. However, if the test is successful, but the sensor behaves strangely in life, the problem lies in the software logic of the system.
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Before testing, be sure to wipe the top of the screen with a soft cloth to exclude the impact of contamination on the test result.
Calibration of the sensor in the MIUI system
One of the most effective ways to solve the problem is to recalibrate, Xiaomi’s system allows you to reset the current sensitivity settings and set new reference values, a procedure that is especially relevant after updating the firmware or replacing the protective glass with the Redmi Note 9.
The calibration process often requires you to log into the same engineering menu that was used to test, and unlike a simple test, you have to do a series of things: remove your hand from the sensor, press the calibration button, then close the sensor and press the button again, and the system will determine the upper and lower trigger thresholds.
It's important to do everything consistently and take your time. If the calibration is successful, you'll see a message that's relevant. Some versions of MIUI may require you to reboot your device to apply new parameters. This is a standard procedure that doesn't affect your personal data.
☑️ Calibration checklist
Use of third-party applications for management
If Xiaomi’s regular tools don’t allow flexible sensor behavior, Google Play apps come to the rescue, and programs like Proximity Sensor Reset & Test or Less Touch can intercept sensor signals and control the screen using their own algorithms, which bypasses the system limitations of the shell.
These applications often have a function of “ignore the sensor when unlocking” or “delay the screen off,” which is especially useful for users who are used to holding the phone in a certain way.
Some tools allow you to create profiles for different situations, for example, during the day the sensor can work in standard mode, and at night, when you use the phone as an alarm clock or for reading, its operation can be completely suspended by software.
- 🛠 Proximity Sensor Reset: A special application for resetting and fine-tuning sensitivity.
- 📞 Less Touch: A utility for controlling the screen during calls, allows you to ignore the sensor.
- ⚙️ ADB AppControl: A tool for managing system components through a computer.
- 🔧 Engineer Mode: Apps to access hidden Android features without codes.
⚠️ Warning: When installing applications from unknown sources, make sure they are safe by checking reviews and permissions to avoid infecting your device with malware.
Disconnection through ADB and system commands
For advanced users who want to gain full control of the system, there is a method to disable the sensor through the ADB debugging bridge (Android Debug Bridge), which requires connecting the Redmi Note 9 smartphone to the computer and having drivers installed.
Before you start, you need to activate the developer mode. To do this, go to Settings → About Phone and quickly click on the build number seven times. Then, in advanced settings, turn on USB Debugging. Connect the phone to your PC and open the command prompt.
adb shell pm disable-user --user 0 com.android.providers.sensorExecuting this command will disable the sensor data provider. Note that the name of the package may vary depending on the Android version and the MIUI shell. Once the command is executed, the sensor will stop responding to the approach, and the screen will burn constantly during the call. To return changes, use the command instead of disable-user.
Risks of using ADB
Comparison of problem-solving methods
The best solution depends on your technical background and the severity of the problem, and below is a table comparing the methods reviewed for efficiency, complexity, and security for the device.
| Method | Difficulty | Efficiency | Risk to the software |
|---|---|---|---|
| Film removal/cleaning | Low. | High (if the cause is mud) | Absent. |
| Calibration in CIT | Medium | Tall. | Minimum |
| Third-party annexes | Low. | Medium | Low. |
| ADB teams | Tall. | Maximum | Medium/High |
As you can see from the table, it's always the least invasive thing to start with. Physical cleaning and calibration helps 90 percent of the time. ADB-The commands should be considered as a last resort when other methods are exhausted.
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The safest and most effective solution for most users is recalibration through the CIT engineering menu, as it does not require the installation of third-party software.