Where in Xiaomi proximity sensor: the complete guide

Xiaomi smartphone owners often face a situation where the screen does not go out during a phone conversation when the device is held to the ear, which leads to accidental tapping of the cheek or ear, which can interrupt the dialogue or launch third-party applications. The proximity sensor is a tiny but critical interface element responsible for locking the display at the right time.

Understanding where the sensor is physically located and how it interacts with the software will help quickly diagnose the problem. In modern Xiaomi, Redmi and POCO models, manufacturers are experimenting with placement technologies, which sometimes causes confusion among users who are used to classic solutions.

In this article, we will take a closer look at the physical location of the sensor across different series of devices, explain the difference between virtual and hardware sensors, and provide step-by-step calibration instructions. 90% of the time, the failure is not due to a breakdown, but to software failure or contamination of the protective glass.

Physical location of the sensor in different models

The answer to where the sensor is is depends on the year of release and the price segment of your device. In classic smartphones with wide bezels on the top and bottom, the sensor is usually a small black window next to the speaker.

In budget and mid-budget models like the Redmi Note series or the POCO M, the sensor is most often hidden under the screen's protective glass at the top of the screen, a so-called "virtual" sensor that has no physical hole in the case. Its work is based on changing the brightness of the pixels and analyzing reflected light, making it less sensitive to contamination but more dependent on protective films.

Flagship models and devices with notch or hole-punch notches often use more complex systems, where the sensor can be integrated directly into the front camera module or placed in the thinnest bezel above the display. It is important to understand that the location of the sensor affects its susceptibility to external factors such as glare or paste accessories.

• 📍 Classic location: narrow strip above the screen next to the speaker grid (models up to 2018).
• 📍 Hidden sensor: The area at the top of the screen, often left or center, is not visible visually (most modern Redmis).
• 📍 Integrated sensor: built into the camera module or subdisplay space (the flagships of Mi and Xiaomi).

If you're not sure what type of device you're wearing, try making a call and closing the top of the screen with your hand. If the screen goes out when you close the area above the display, you have a classic sensor. If you only react when you touch the matrix, the sensor is virtual.

Differences between hardware and virtual sensor

The technological separation of sensors into hardware and virtual is key to understanding why they don't work properly. A hardware sensor is a physical component that emits infrared light and reads its reflection, independent of screen brightness, and works even when the display is off in standby mode.

The virtual sensor, which is widely used in the MIUI ecosystem, works differently: it uses light from the screen itself, which is reflected off the object (ear) and read by the photosensor, which allows manufacturers to make the frames thinner, but creates a dependence on the brightness of the display and the quality of the protective film.

⚠️ Attention: The use of thick protective glasses or films with a black frame that covers the top of the screen often leads to a complete blocking of the virtual sensor.

The difference also manifests itself in the reaction speed: hardware solutions tend to fire instantly. Virtual solutions can have micro-latency, because the system takes time to analyze the change in the lighting of the pix.

It's worth noting that some models are hybrid systems, where the main sensor can be virtual, but when you call, the system uses additional data from the gyroscope and the accelerometer to understand that the phone is held to the ear, and force the screen to be extinguished.

How to check the operation of the proximity sensor

Before you bring a device into service or reset your settings, you need to do a diagnostic, and the MIUI and HyperOS shells have powerful hardware testing tools built in, and the easiest way is to use an engineering menu that is available without root rights.

To run the test, open the Phone app and dial the combination ##6484##. The CIT menu will open. You will need to find the "Proximity sensor" or "Proximity Sensor" in the list. You will enter the testing mode by clicking on it.

The sequence of actions for verification:


1. Close the top of the screen with your palm.




2. Put your hand away.




3. Watch for changes in values (Far/Near or 0.0/5.0).

In the test mode, you'll see numerical values or statuses. When the hand is removed, the status should be Far (far) or 0.0. When you close the sensor with your hand, the status should change to Near (close) or the value will change to 5.0. If the numbers "jump" or status does not change, calibration is required.

Calibration of the sensor through the engineering menu

If the test shows that it's not working properly, the next step is to calibrate, which trains the controller to remember current light levels as normal, which takes less than a minute and is safe for the device.

When you're in the sensor test menu (as described in the previous section), you'll see two buttons: "Calibrate" and "Pass" first, remove all items from the top of the screen to give it a straight light, and press "Calibrate."

After the first press, the system may ask you to close the sensor. Follow the instructions on the screen: usually close the top of the phone with your palm and press the calibration button again. Successful completion will be confirmed by the message "Calibration success" or a green indicator.

After a successful calibration, be sure to press the "Pass" button to save the results and exit the test. Reboot the smartphone to apply the changes. In most cases, this returns functionality to the sensor without the need for deep intervention.

Sensitivity settings in the Android system

Some versions of Android and MIUI have the ability to program sensitivity adjustment, especially for devices with virtual sensors that may be too sensitive to the light in their pocket or ignore their finger.

To access the advanced settings, go to Settings → About Phone and quickly click on the MIUI version several times until you see the words "You became a developer." Then go back to the main settings menu, select Additional → For developers.

In the list of engineering options, find the section associated with the sensors. There may be a "approach sensor" item with a sensitivity slider. Move the slider and test the operation during the call. You should not set maximum values, because this can lead to false positives.

• 📉 Low sensitivity: The screen may not go out if you hold the phone slowly.
• 📈 High sensitivity: The screen may go out in your pocket or when the phone is moving in your face.
• ⚖️ Optimal setting: balance, in which the screen goes out only when tightly fitting to the ear.

⚠️ Note: Changing the settings in the Developer Menu may affect other system functions. Write down the initial settings before changing them.

Influence of protective accessories and covers

One of the most common reasons why the proximity sensor stops correctly detecting distance is because of the wrong protective accessories, a common but common problem that is often overlooked.

Black-framed protective glass for wide-frame models can completely block the virtual sensor area on modern bezelless devices. The light from the screen simply cannot penetrate the opaque film, and the sensor "thinks" that the phone is closed all the time.

Tight bookcases or bumpers with high sidebars can also create shadow in the sensor area. If the side of the cover hangs over the top of the screen, it can block IR radiation, in which case only replacing the accessory with a more suitable geometry helps.

Check the integrity of the security glass. Cracks or severe scuffs at the top of the screen scatter light, which confuses the algorithms of the sensor. A temporary solution may be to turn off the "Conversation Lock" function, but this is inconvenient in the sensor.

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Try temporarily removing the security glass or case and running a call test, and if the problem is gone, it's the accessory, not the smartphone itself.

Frequently Asked Questions (FAQ)

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In most cases, the problem is solved by removing the protective film or recalibrating through the CIT engineering menu, without requiring contact with the service center.