How to easily recalibrate the proximity sensor on Android

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If your phone does strange things when you make calls, like hang on the cheek, turn on the speaker or Your screen doesn't turn off when you callThe proximity sensor is almost certainly the culprit. It's a tiny component, usually hidden at the top of the phone, but it has a much greater impact on daily use than you might think.

The good news is that, in most cases, you can Easily recalibrate, adjust, or reset the proximity sensor on Android y recognize and repair sensor faults without having to go through technical support. And when the fault is physical, there are also clear clues to detect it and avoid wasting time with solutions that won't work.

What is a proximity sensor and why is it so important?

In a modern smartphone, the proximity sensor is a transducer capable of detecting very close objects to the front of the device, especially in the earpiece area. Its main function is to turn off the screen and lock the touchscreen when you bring the phone to your ear during a call or when listening to audio messages from apps like WhatsApp or Telegram.

By turning off the screen when it detects your face, the system prevents you accidentally crash, open strange menus, or activate features simply by touching the panel with your cheek. It also helps save battery, as the panel doesn't stay on while you're talking.

On most Android phones, the sensor is usually located in the top front of the mobile phone, next to the earpiece speaker or even integrated under the screen itself in models with very thin bezels. In these cases, its performance can be more delicate, because any poorly cut screen protector, a thick case, or dirt in that area has a much greater impact.

In addition to its function in calls, in many devices the sensor is involved in gesture functions and audio playbackWhen you bring the phone to your ear while listening to a voice note, the system turns off the screen and switches the sound from the external speaker to the earpiece, maintaining privacy.

Types of proximity sensors and related technologies

Although they may all look the same at first glance, there are several types of proximity sensors in electronics. Not all of them are used in mobile phones, but understanding them helps to see Why some phones fail more than others with this component.

Photoelectric (infrared) proximity sensor

The one most traditionally used in smartphones is the infrared photoelectric sensorIt combines an emitter (a small IR LED) and a receiver (photodiode or phototransistor): the emitter sends an infrared light beam outwards and the receiver measures the light that bounces off your face, hand or any nearby object.

When the amount of reflected light exceeds a threshold, the system interprets that There's something stuck to the front of the phone. Then it turns off the screen and disables the touch function. It's a fairly reliable and simple system, inherited from industry and robotics, where coded signals are also used to differentiate transmitters, although it's much simpler in mobile devices.

ultrasonic sensors

Ultrasonic sensors work by emitting inaudible high-frequency sounds that bounce off objects and return to the microphone. By measuring the time and intensity of the echo, the device calculates how far away the object is.

In robotics, these sensors can detect objects several meters away and with very different shapes and materials. In mobile phones, the range is reduced, and they also usually work in combination with other sensors (accelerometer, gyroscope, microphones) and with software algorithms that decide when to turn the screen on or off. They are cheaper and allow for designs with almost no bezels, but they are also more sensitive to calibration errors, ambient noise, and position changes.

Magnetic sensors and other nearby sensors

The industry is also full of magnetic proximity sensorsMagnetometers detect magnetized objects even through certain non-magnetic materials. They are used for automation, door detection, limit switches, etc. In mobile devices, a magnetometer is usually found as a digital compass, not as a proximity sensor, so it's important not to confuse them.

Along with the proximity sensor, a modern smartphone incorporates a good array of sensors: accelerometer, gyroscope, barometer, ambient light sensor, battery and temperature sensors, fingerprint reader, biometric sensors…They all work together for functions such as automatic rotation, augmented reality, energy saving, or advanced unlocking.

Physical sensors versus virtual proximity sensors

In recent years, especially in brands like Xiaomi, Redmi, and POCO, some models have replaced the classic optical sensor with a virtual proximity sensor based on ultrasound and other sensors already present in the device. The best-known provider in this field is Elliptic Labs, with its INNER BEAUTY technology.

In these phones, the terminal emits a ultrasonic signal from the top of the screen towards the earThe secondary microphone picks up the echo, and if the signal returns sooner than expected or with greater intensity, the system understands that there is an object very close (your ear or cheek) and turns off the screen. The gyroscope also plays a role, as it helps recognize the gesture of bringing the phone to your head.

This approach reduces costs and frames, but it's much more delicate. A small software glitch, a poorly designed case, ambient noise, or a change in how you hold the phone can cause the The screen turns off for no reason or stays on when it shouldn't.generating the typical feeling that "the sensor works when it wants to."

Xiaomi, Redmi and POCO models with more proximity problems

The shift to virtual proximity sensors sparked a wave of complaints in the community, especially in Xiaomi, Redmi and POCO devices released around 2020. Many users reported that the phone did not turn off the screen during calls or that it turned on by itself with the slightest movement.

Among the models that accumulated the most negative comments on this issue are, among others, series like Xiaomi Mi 10T, Mi 10T Pro, Mi 10T Lite, Mi Note 10 Lite, Redmi Note 9, Redmi Note 10, Redmi Note 10 Pro, Redmi Note 11 and some POCO models like the M4In many of them, the sensor is under the screen and depends almost entirely on the MIUI or HyperOS software.

The problem was so widespread that Xiaomi even went so far as to open a specific investigation, asking users through surveys in what situations the sensor failed (calls, WhatsApp, other apps) and under what circumstances (phone position, type of case, environment, etc.), with the intention of adjusting the system through updates.

Meanwhile, the community itself found homemade solutions by resorting to Xiaomi's CIT menu for recalibrating the proximity sensor, tricks to change the sensitivity or even alternative ROMs (like CyanogenMod and successors) that handled face detection differently.

Typical symptoms of a poorly calibrated proximity sensor

When a physical or virtual proximity sensor fails, the signs are usually the same in almost any make or model. The most common is that The screen doesn't turn off when you bring the phone to your ear. during a call. Since the panel remains active, any touch with your face can end the call, activate the speakerphone, put you on hold, dial numbers, or open menus you didn't even know existed.

Another very common symptom is the opposite: The screen remains completely black during the call. And there's no way to turn it back on when you take the phone away from your ear. In these cases, until the other person hangs up or ends the call, you're "stuck" and unable to do anything.

The glitches are also very noticeable with voice notes. Typically, when you bring the phone close to your face while listening to a WhatsApp or Telegram audio message, the sound switches from the external speaker to the earpiece and the screen turns off. If the calibration is poor, the system can abruptly cutting off the audio, switching speakers for no reason, or making erratic skips between one and another.

They also confuse warning messages like the classic “Do not cover the earpiece areaThis notification doesn't refer directly to the proximity sensor, but rather to the earpiece speaker, warning against covering it with your hand, phone case, or other objects. Even so, many people interpret it as a sensor malfunction.

User forums repeatedly mention cases where, after replacing a broken screen with a new one, the proximity sensor fails, especially indoors: It only works in bright light or if a flashlight is pointed at the sensor.This points to a conflict between the installed replacement part, the sensor calibration, and how ambient light affects its reading. That's why it's important calibrate your mobile phone screen after the replacement and checking the panel's compatibility.

External factors that impair detection

Before you start calibrating, entering hidden menus, or installing third-party applications, it's a good idea to rule out basic causes that are responsible for many proximity problems: dirt, poorly fitted covers and protectors.

The sensor area, at the top front, is a magnet for dirt: skin oil, dust, makeup, sweat, hair product residueOver time, a film can form that blocks infrared light or interferes with the passage of ultrasound waves. Something as simple as thoroughly cleaning that area with a microfiber cloth and a little isopropyl alcohol often makes a difference.

Screen protectors and cases are also largely to blame. If the protector's cutout partially covers the sensor, or if the case adds a thick lip directly above it, the system interprets it as incorrect. The quickest test is... Temporarily remove cover and screen protectorMake several calls and check if the behavior improves or not.

In the case of replaced screens, it is important to make sure that the replacement is actually compatible with the specific model and its sensor typeAlthough the catalog may show two "identical" screens, the position or treatment of the sensor area may vary, and this affects sensitivity, especially indoors or in low light.

Is it really necessary to calibrate the sensors on Android?

Google Play is full of apps that promise to calibrate all your phone's sensors in just a couple of taps, but the reality is that Most sensors come factory calibrated and they rarely lose those parameters unless there is physical damage or major software errors.

Calibration values ​​are usually stored in system files or protected partitionsTo seriously modify them, root access or system privileges are almost always required. Many applications that don't request superuser permissions are limited to reading data, resetting caches, or applying "settings" within the app itself, without making profound changes to the system.

Therefore, when we talk about recalibrating the proximity sensor, it is much more reliable to use the official manufacturer tools and internal test menus (like the CIT in Xiaomi) or options for Android developers, who create shortcuts to turn sensors on and off.

Even so, there is at least one specialized app like “Proximity Sensor Reset (+Overrider service)Designed for rooted devices, this app attempts to rewrite the configuration file values ​​of some Android sensors. The developers themselves clarify that it can only fix software issues and that no other app will be able to repair a hardware fault in the sensor.

How to see which sensors your mobile phone has and check if they respond

If you want to know what sensors your phone has and whether the proximity sensor is working correctly, you can use diagnostic tools such as Multi-tool sensors, Sensor Box, or similar appsThese applications display real-time values ​​returned by sensors without requiring any deep configuration changes.

With them you can check if your device integrates proximity sensor, gyroscope, magnetometer, ambient light sensor, barometer and others. In the case of the proximity sensor, simply cover the top front of the phone with your hand and see if the value changes from "far" to "near" or from a high number (for example 5) to a low one (0).

If, after covering and uncovering the top area, the value remains the same or no proximity sensor appears in the list, you have indications that the problem goes beyond a simple software miscalibration or failure and perhaps it is a physical defect in the component.

Activate and deactivate the proximity sensor in Xiaomi (MIUI)

On many Xiaomi phones with MIUI, especially in versions like MIUI 11 and some branches of MIUI 12, there is a dedicated switch to activate or deactivate the proximity sensor during calls. The exact path may vary depending on the version, but it usually involves the system settings.

The usual route is to go to Settings > Apps > System app settings > Call settings > Incoming call settingsWithin this last section, you will usually find an option called "Proximity Sensor" that you can activate or deactivate.

If your phone doesn't turn off the screen when you make a call, first check that this switch is enabledA very useful trick is to disable it, restart the device, and then re-enable it after the restart. This cycle forces MIUI to refresh the settings and, in some cases, restores normal functionality.

In more recent versions of MIUI 12.5, MIUI 13, or even HyperOS, this setting may have moved or disappeared from the visible interface, leaving the Sensor management is entirely in the hands of the system. There's no option for the user. Even so, it's worth checking the call menus in case your specific model still displays the selector.

Calibrate the proximity sensor on Xiaomi using the CIT menu

Xiaomi, Redmi, and POCO phones include a hidden testing menu called ITC This allows testing and, in some cases, calibration of various internal components, including the proximity sensor. Access is granted using a code entered via the phone application.

On most devices, simply open the phone app and dial the code. * # * # * # * # 6484As soon as you enter the last character, without pressing the call button, the CIT screen will automatically open with a list of numbered tests.

Within the CIT, look for an option called “Proximity Sensor Test" or simply "Proximity sensor". Its position in the list varies depending on the model, but it's usually in the middle. Once you access it, you'll see a value that changes when the phone detects proximity.

The basic test consists of cover the upper front area with your hand From the phone, right where the sensor is located, check if the value changes from a high number (for example, 5) to a low number (0) when you cover it, and returns to its initial state when you uncover it. If it responds correctly, at least you know that the hardware is reacting.

On some Xiaomi devices, an explicit button appears within this screen for “CalibrateWhen you press it, the system usually asks you to place the phone on a flat surface, with nothing in front of the sensor, and completes the calibration in a few seconds. It's important to do this without a case or screen protector that might obstruct the area, and after cleaning it thoroughly.

Additional calibration and sensitivity adjustment options in CIT

On certain models, the direct calibration option doesn't appear when you enter the CIT proximity test. This doesn't mean there aren't advanced settings. In the upper right corner, you'll often see a three point icon which displays a menu of “Additional tools”.

From there, there is usually a specific subsection for the proximity sensor with additional controlsIn it you can repeat the test of covering and uncovering to see how the values ​​change and, if the sensor responds but does so erratically, adjust the sensitivity.

In some cases, the solution lies in increase sensitivity until, when the top of the phone is covered, the value changes correctly and MIUI recognizes the proximity without the need for a strong light source in front, something that is usually very noticeable between indoors and outdoors.

Once you get the sensor to respond with some stability, CIT itself allows you to mark the test as "Pass". This saving process ensures that Apply the new parameters for the daily operation of the device.

Reset all sensors from developer options

Android doesn't include a direct button to reset only the proximity sensor, but it does offer a function in the developer options that allows you to do so. to disable all phone sensors at once and reactivate them, which in practice acts as a small reset.

To use it, you must first enable the developer menu. Go to Settings> Phone information Then tap repeatedly on the "Build number" until the system notifies you that developer options are enabled. In some versions, this is done on the Android or MIUI version, but the concept is the same.

Then go back to Settings, enter “System” or the equivalent section of your skin and open the new “Developer Options” menu. Inside, use the search bar to locate the function called “Sensors deactivatedActivating it will add a new icon to the quick settings panel.

Open the quick settings panel and tap the "Sensors off" icon. The phone will disconnect. all sensors: temperature, motion, battery, proximity, etc.After a few seconds, tap the icon again to reactivate them. This power cycle usually fixes temporary glitches, provided the problem isn't a hardware defect or a serious ROM bug.

Other practical solutions before restoring your mobile phone

If after cleaning the phone, removing the case and screen protector, checking the MIUI switch, recalibrating from the CIT, and resetting the sensors the problem persists, you can still try several intermediate measures before completely formatting or going to a technical service.

The first, though it sounds obvious, is to restart the device. Often a internal process gets stuck And the system that manages the proximity sensor stops responding properly. Turning the phone off, waiting a few seconds, and turning it back on solves more problems than you might think.

It is also advisable to check if there are pending software updatesManufacturers often fix sensor bugs with patches in MIUI, HyperOS, or whatever skin your phone uses. On Xiaomi devices, you can go to Settings > About phone and tap on the MIUI/HyperOS version to force a search for updates.

Another very useful test is to start the mobile phone in android safe modeIn this mode, all third-party applications are temporarily disabled. If the proximity sensor works fine in safe mode, but fails again when starting normally, it's almost certain that an installed app is interfering. You'll need to uninstall the most recently installed or suspicious apps one by one until you find the culprit.

Some Xiaomi models offer the option to Reset only app settings and data without deleting photos, videos, or personal files. It's usually found in Settings > Additional settings > Factory data reset, where you can choose to restore only apps and settings. If the issue stems from a settings conflict, this step can restore the sensor to stable behavior.

When to completely restore your mobile phone and go to a technical service center

If, after exhausting all the previous options, the proximity sensor still doesn't work or behaves completely unpredictably, it's time to consider a full factory reset or a visit to the technical service.

Before restoring, do a backup your important dataPhotos, videos, chats, documents, etc. Then go to Settings > Backup and reset (or the equivalent menu for your device) and choose to erase all data from the device.

When the phone finishes the process and starts up as if it were new, configure the bare minimum and Test the proximity sensor before restoring apps and backupsIf the fault persists in that "clean" state, it is a very clear sign that the problem is with the hardware or the design of the specific model.

In that scenario, the best course of action is to go to official technical service or a trusted service centerIf the device is still under warranty and the defect isn't related to impacts, drops, or moisture, the manufacturer should cover it. Otherwise, they'll give you a quote, and you can decide whether it's worth repairing or better to get a new phone, especially with models that have virtual sensors, which are known for being problematic, and where the final decision usually rests with the manufacturer.

Why some users prefer to disable the proximity sensor

Although it may seem surprising, some people choose to go straight to disable proximity sensor on your phone when the option is available. On Xiaomi, in some models, the switch is in the MIUI call settings, as we've seen.

One of the reasons is privacy. Some users don't want any app to be able to access their personal information. use the sensor to measure gestures, usage times, or patternsAlthough Android severely limits access to sensors, some people prefer to play it safe and turn it off just in case.

Another common issue relates to the use of voice notes. Some users complain that while listening to a WhatsApp or Telegram audio message, a simple movement or change of hand causes the sensor to interpret that they are about to bring the phone to their ear, switching to the earpiece, lowering the volume, or stopping playback. In these cases, disable the sensor during calls and audio recordings Avoid these changes, at the cost of accepting the risk of unintentional screen touches.

If you decide to try this method and your Xiaomi allows it, go to Settings > Apps > System app settings > Call settings > Incoming call settings And uncheck the proximity sensor option. If you then start accidentally hanging up calls with your face or activating the speakerphone, you can always re-enable the sensor and apply the other solutions we've discussed.

Taking care of the physical part of the phone, using the official diagnostic and calibration tools By keeping the software updated, most proximity sensor problems on Android are resolved without major issues. Only when all else fails does a complete reset or professional repair make sense, especially on models with virtual sensors, which already have a reputation for being problematic, where the final decision usually rests with the manufacturer.