What is a proximity sensor and why it is needed in Xiaomi smartphones
The proximity sensor is a small but critical component in Xiaomi smartphones that is responsible for automatically turning off the screen during a call. When you hold the phone to your ear, the sensor picks up the obstacle and extinguishes the display, preventing accidental tapping of the cheek or ear. Without this sensor, the screen would remain active, leading to disruptions during a conversation: accidental pressing, transferring the call to the speakerphone or even resetting it.
In Xiaomi smartphones (including the Redmi, POCO and flagship Mi and Xiaomi 13/14), the proximity sensor is usually located at the top of the screen, next to the speaker and the front camera. It works on the basis of infrared radiation: it emits an invisible beam and analyzes its reflection from objects. If the beam returns with a delay or distortion, the sensor knows that there is an obstacle nearby (for example, your ear or case).
The proximity sensor problem is one of the most common complaints of Xiaomi users: the screen may not go out during a call, turn on spontaneously in your pocket or turn off for no reason, most often due to incorrect calibration, sensor contamination or software failures, and fortunately, most faults can be fixed on their own without going to the service center.
How to check the work of the proximity sensor on Xiaomi
Before you set up or calibrate the sensor, make sure it's really faulty. Use built-in MIUI tools or third-party apps to do that. Here are three reliable diagnostic methods:
- 📱 Testing through the engineering menu: dial the phone code ##6484### (or #4636### on some models). In the menu that opens, select Proximity Sensor and check the sensor response by covering it with your hand.
- 🔍 Third-party apps: Install tools like Sensor Test or Phone Tester from Google Play, which will show the current sensor values in real time.
- 📞 Practical test: call another phone and see if the screen goes out when you put it in front of your ear.
If the sensor does not respond at all (the test values are always 0 or 5.0 cm regardless of the obstacle), this may indicate a hardware malfunction, such as a plume break or a sensor failure, in which case repair is required. If the reaction is not stable (values jump from 0.1 cm to 5.0 cm for no reason), the problem is more software-based and is solved by calibration.
Step-by-step: how to calibrate the proximity sensor
The Xiaomi proximity sensor calibration is done through hidden MIUI settings, which resets the current sensor settings and sets new values to match real-world conditions. Importantly, before calibrating, make sure that the sensor is not directly exposed to sunlight and the screen is clean (no film, glass or dirt).
Follow this instruction:
- Open the Phone app and enter the code ##6484## (on some models, POCO may work ##4636###).
- In the engineering menu, select Proximity Sensor.
- Press Calibrate, and the system will suggest that you close the sensor with your hand.
- Completely close the top of the screen (where the sensor is located) with your palm and hold for 3-5 seconds.
- After the beep, remove your hand. Calibration complete.
If the engineering menu is unavailable or the code doesn’t work, try an alternative method via Settings → About Phone → MIUI version. Click on the line with the version 7-10 times in a row until the developer mode notification appears. Then go back to Settings → Additional → For Developers and find the Calibration of the proximity sensor.
Make sure there is no protective film or glass on the screen.
Clean the top of the display from dirt and dust
Close all applications running in the background
Calibrate indoors in normal lighting-->
Setting the sensitivity of the proximity sensor in MIUI
Some MIUI firmware (especially older versions) have the ability to manually adjust proximity sensor sensitivity, which is useful if the sensor is triggered too late (the screen is late) or, conversely, responds to false positives (for example, in a pocket).
To change the sensitivity:
- Go to Settings → System and device → Additional settings.
- Select Sensors (on some models, the item may be called Sensor Management).
- Find the proximity sensor and tap it.
- Move the slider Sensitivity to the position from Low to High:
| Sensitivity level | When to use | Possible side effects |
|---|---|---|
| Low. | If the screen goes out too early (for example, with a slight tilt of the phone) | It may not work when pressed tightly to the ear |
| Medium | Optimal balance for most users | In rare cases, false positives may occur in your pocket. |
| Tall. | If the screen does not go out during the call, even when pressed tightly | Frequent failures when using covers or protective glass |
On the new versions MIUI 14/15 The manual sensitivity setting can be hidden, so you can only calibrate or reset the sensor through the engineering menu. If the problem persists after the changes, try resetting the network settings (Settings). → SIM-maps and mobile networks → Reset network settings, as sometimes conflicts arise due to incorrect communication parameters.
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If the sensor is still unstable after calibration, try temporarily disabling the Smart Block function in the security settings.
What to do if the proximity sensor does not work after the MIUI update
One of the most common causes of proximity sensor failures is a firmware update, and once a new version of MIUI is installed (especially major updates like the switch from MIUI 13 to MIUI 14), sensor settings can be lost or driver conflicts can occur, and this is what will help you get back up to speed:
- 🔄 Reboot your phone: Sometimes a normal reboot is enough to make the sensor drivers boot correctly.
- 📥 Install the update again: go to Settings → The phone. → Update the system and click "Check Updates." If the same version is available, install it on top of it.
- 🧹 Clear the system cache: in the recovery menu (Switch off) → Hold the power button. + Volume up, select Wipe cache partition.
- 🔧 Reset to factory settings: extreme method if nothing works.
If the problem occurs after upgrading to MIUI 14 or HyperOS, check for firmware beta. In some cases, sensor bugs are only fixed in stable releases that come out 1-2 months after major updates.
If the sensor stopped working after rolling back on the previous version of MIUI, the driver incompatibility may be the cause, in which case only a complete flashing through Fastboot will help, cleaning all partitions.
What if the sensor doesn’t work after reset?
Problems with the proximity sensor due to covers and protective glasses
Many Xiaomi users experience a proximity sensor that fails after installing a cover or protective glass, and the reason is simple: the infrared signal that the sensor emits can be reflected or absorbed by foreign materials, especially critical for:
- 🛡️ Metal covers – they shield the signal, because of which the sensor does not “see” the obstacle.
- 🧲 Magnet covers – magnetic field can affect the sensor.
- 🔳 Thick protective glasses (from 0.5 mm and above) - they scatter the infrared beam.
- 🖼️ Film with mirror or matte coating - change the reflection of the signal.
Decisions:
- Take off the case and check the sensor without it, and if the problem is gone, replace the case with a model with a sensor cutout.
- If you use glass, choose the option with the opening for the proximity sensor (such are sold for most Xiaomi models).
- Try recalibrating the sensor with the case/glass installed – sometimes this helps the system adapt to new conditions.
On some models (such as the Xiaomi 13 Pro or Redmi Note 12 Pro+), the proximity sensor is combined with the light sensor, in which case even thin film can affect its operation, if you notice that after installing the protection, the screen becomes dim or the brightness is not adjusted correctly, this is an indirect sign of a problem with the sensors.
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If the proximity sensor starts to fail after installing the case or glass, in 90% of cases the problem is solved by replacing them with compatible accessories with sensor cutouts.
Software Solutions: Applications for Testing and Correcting the Sensor
If the built-in MIUI tools don't work, you can use third-party apps to diagnose and configure the proximity sensor.
- 📊 View current sensor values in real time.
- 🔧 Calibrate the sensor by alternative methods.
- 🚨 Receive notifications of failures in work.
Top.-3 tested applications:
| Annex | Functions | Reference |
|---|---|---|
| Sensor Test | It shows the values of all sensors, including approximations. | Google Play |
| Phone Tester | Tests sensors, cameras, speakers and other components. There's calibration. | Google Play |
| Proximity Sensor Reset | Specialized application for resetting the proximity sensor settings. | Google Play |
Warning: Some apps require root rights to fully calibrate. If your Xiaomi isn't rooted, only use features that are available without additional permissions. Also beware of programs that promise "magic fix" to the sensor - often this is a scam.
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If you use custom firmware (like LineageOS or Pixel Experience), the sensor problem may be due to the lack of drivers.Try to install a kernel that is compatible with your Xiaomi model.
When repairs are required: signs of sensor hardware failure
If all software methods have been tried and the proximity sensor still doesn't work, the reason is probably hardware.
- ❌ The sensor does not respond to any obstacles (values in the test are always 5.0 cm or 0).
- 🔥 The screen goes out or lights up chaotically, with no connection to the phone’s approach to the ear.
- 💥 There are cracks or chips on the screen at the top (where the sensor is located).
- 🌡️ The phone overheats in the upper frame area (may indicate a short circuit in the sensor).
The cost of replacing the proximity sensor in the service center varies from 500 to 2000 rubles depending on the Xiaomi model. On popular devices (for example, Redmi Note 10/11 or POCO X3/X4), repair is cheaper, since parts are common. On flagships (Xiaomi 13 Ultra, Mix Fold), the price can be higher due to the complexity of disassembly.
⚠️ Note: if you choose to replace the sensor yourself, note that on most Xiaomi models it is glued to the screen or integrated into the front camera module.
Before visiting the service center, check if your smartphone warranty has expired. If the phone is warranty, repairs must be free (provided that the breakdown is not caused by mechanical damage). To check the warranty status, go to mi.com/verify and enter your device's IMEI.