How to Remove Screen Dimming on Xiaomi When Calling: The Complete Guide

The situation when the screen of Xiaomi smartphone suddenly goes out during a conversation is familiar to many users. You hold the phone to your ear, the image disappears, but as the device moves away, the screen continues to glow black, making it impossible to dial a number or turn on the speakerphone. This is not just an annoying bug, but a common problem associated with the operation of the proximity sensor or software conflicts in the MIUI shell.

The main reason for this behavior is the standard algorithm of any modern smartphone: the system reads the sensor readings and blocks the display to prevent accidental cheek pressing. However, if the calibration is knocked down or the protective film overrides the sensor, the phone “thinks” that it is still in your ear. In this guide, we will examine all methods of troubleshooting, from simple settings to deep diagnostics.

It's worth noting that the problem can be both software and hardware, and owners of Redmi Note, Poco and Mi flagships face it at different times, sometimes with a simple reboot, and other times with an engineering menu or even a component replacement, let's figure out how to take full control of the device.

Principle of operation of the proximity sensor and causes of failures

The locking is done by a special infrared sensor at the top of the display, which emits invisible light and analyzes its reflection from objects. When you bring the phone to your face, the light reflects faster, and the system receives a lock signal, and if the screen does not light up after the device is removed, then the unlock mechanism has received a false signal or has frozen.

Often, third-party accessories are the culprits: a thick protective glass, a poor quality film or a high-sided case can physically overlap the sensor area, and even a microscopic crack in that area can distort the sensor readings, making the system think that the object is in close proximity, in which cases software methods may not help.

From a software perspective, the bug can be in the cache of system services or in conflict after the Android update. The MIUI shell has its own features of handling interrupts from sensors. Sometimes the background processes "stick" and the command to turn on the display simply does not go to the screen controller, although the call is already underway.

⚠️ Warning: If the screen goes out and doesn't light up even after the call is complete, try pressing the power button quickly.This will force the display to wake up and allow the call to be completed if the touchpad is still unresponsive.

It is important to understand the difference between dimming to save energy and locking by the sensor: in the first case, the screen dims after a predetermined time of inactivity, in the second - instantly when the upper frame is blocked. To diagnose the problem, you need to eliminate physical obstacles and check the integrity of the protective glasses.

Basic settings of the call interface in MIUI

Before you go to the engineering menus, check the standard settings of the Phone app. In the Xiaomi shell, the com.android.incallui component, which has its own display options, is responsible for this. Go to the Phone app, click on three dots in the corner and select Settings.

In the menu that opens, look for the Incoming Calls or Interface section, and there may be a "Mode in your pocket" option or a similar feature that enhances sensor sensitivity, and disabling this feature can solve the problem if it is caused by excessive sensitivity of the system to dimming.

Also worth paying attention to is the design theme. Some third-party themes downloaded from MIUI Themes store may contain errors in the code of the call interface. If the problem occurred after the visual style change, return the standard theme "Classic" or "Basic" and check the sensor.

• 📱 Open the Phone app and go to settings via the menu.
• 🔍 Find the Incoming Calls item and turn off the additional effects.
• 🎨 Reset the theme to standard to eliminate interface conflicts.
• 🔄 Restart the device to apply changes to system services.

If simple menu manipulations didn't work, the sensor calibration might have gone wrong, so you need to move to more advanced diagnostics available through the device's hidden engineering menu, a secure procedure that doesn't require root rights.

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Sometimes the problem is solved by a simple memory cleanup. Go to Settings → Apps → All apps → Phone and click “Clean” by selecting “Clear cache.” Don’t delete data unless you want to lose your call history.

Calibration of the sensor through the engineering menu

The most effective way to fix a software failure of the sensor is to recalibrate it. To do this, Xiaomi smartphones have a special engineering menu available by code. Open the dialer and dial the combination ##6484##. If the code did not work, try ##4636##, but the first option is preferable for hardware tests.

In the CIT menu that opens, you need to find the "Proximity sensor" item. You click on it and you'll see the current reading. Close the top of the screen with your hand, the value should change from 5.0 to 0.0 (or vice versa, depending on the version). If the values "float" or do not change, calibration is required.

To do this, press the "Calibration" button at the bottom of the screen. Follow the instructions on the display: usually close the sensor with your finger and press OK, then open and press OK again. Once successful, the "Pass" message will appear. This action resets the sensitivity thresholds.

Commands for entering the engineering menu:




1. ##6484## (Main test menu)




2. ##4636## (Phone Information)




##3424## (Alternative test for some models)

After calibration, be sure to restart your smartphone. The system must read new parameters and correctly process the signals from the sensor. If the test shows a constant value of "0.0" even without overlapping the sensor, this may indicate a hardware malfunction or a plume break.

Additional screen settings and functions

Modern versions of MIUI and HyperOS have many features that make it easier to use but sometimes create conflicts, and one of them is Pocket Mode, which is designed to block random taps when the phone is in the bag, but can be activated by mistake when you call.

You can turn this off in Settings → Lock and Protect → Pocket Mode. By removing the tick, you will prevent the system from using the proximity sensor to lock the screen outside of call mode, and this can also have a positive effect on the operation of the call, eliminating dual processing of signals.

Another important parameter is brightness and autobrightness. In some cases, with low brightness and power saving on, the screen may go out too aggressively. Try temporarily turning off the autobrightness in the notification curtain and increase the level of backlight manually during the call test.

Remember that accumulated system debris can also affect the speed of sensor response. Regular cleaning through the built-in Security app helps keep the system in good shape. However, do not abuse the "accelerators" that can force the system processes of the call.

⚠️ Note: Do not install third-party apps to calibrate sensors from Google Play. the built-in engineering menu Xiaomi is quite enough, and third-party software can request unnecessary permissions and disrupt the system.

Influence of protective glasses and accessories

Statistics show that 40 percent of the time, the problem with dimming the screen is not the software, but the physical obstruction. Security glasses, especially those with a black perimeter frame, often overlap the proximity sensor area. Even if the visual hole matches, the thickness of the adhesive layer or the quality of transparency can distort the IR ray.

Try to carefully remove the protective glass or film and check the phone's operation in the "naked" form. If the problem disappears, you will need to purchase an accessory with a cutout for the sensor (the so-called glass "not for the whole screen") or find a model labeled "Compatible with Face ID / Proximity Sensor".

It's also worth checking the dynamic speaker grid, if it gets clogged with dust or pile from your pocket, it can create a fog effect in front of the sensor, clean the top frame carefully with a soft brush, or use a toothbrush to avoid damaging the sensor itself.

• 🧪 Remove the security glass and check the operation of the call without it.
• 🧹 Clean the top frame of the smartphone from dust and pollution.
• 🛡️ Use protective glass with precise cutouts for sensors.
• 🔍 Inspect the sensor area for chipping or cracking.

If you use a high-sided case, make sure it doesn't press on the top edge of the screen.Mechanical pressure can create micro gaps or shift components, leading to false positives. In some cases, replacing the case with a thinner option helps.

Hardware malfunctions and diagnostics

If software methods, calibration and removal of accessories have not helped, there is a high probability of hardware failure. The proximity sensor is a separate module that can fail due to impacts, moisture or production defects, in which case the screen will go out chaotically or not turn on at all.

Notice how the phone behaves after a fall. Even a light impact can unplug the sensor plume from the motherboard or damage the sensor itself. In LCD models, the sensor is often located on the display plume, and in AMOLED, it can be integrated into the matrix itself or placed under glass.

For accurate diagnosis, service centers use a multimeter and an oscilloscope, checking the voltage on the sensor contacts. At home, you can only indirectly judge a malfunction through an engineering menu: if it shows a constant value (for example, always 5.0 or always 0.0) regardless of the position of the hand, the module is defective.

In rare cases, the problem may be due to the outgoing plume of the screen itself. If there are stripes on the display or flickering along with the dimming, it is likely that a replacement of the display module or connector soldering is required.

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If the engineering menu shows the immutable values of the sensor (always 0 or always 5), and the calibration does not help - this is a direct sign of a hardware breakdown that requires a visit to the service.

Frequently Asked Questions (FAQ)