Xiaomi’s Approximation Sensor: Why It Doesn’t Work and What to Do About It

The proximity sensor in Xiaomi smartphones is a small but critical element that is responsible for automatically turning off the screen when you hold the phone to your ear. Its malfunction leads to accidental pressing, rapid battery discharge and discomfort when talking. If your Redmi, POCO or Mi stopped responding correctly to the approach of the hand or face, do not rush to carry it into the service: in 80% of cases, the problem can be solved by yourself.

In this article, we will look at all possible causes of malfunctions, from commonplace contamination to hardware breakdowns, and give step-by-step instructions for diagnosis, calibration and repair. AMOLED-screens (for example, Xiaomi 13 Pro or POCO F5), where the sensor is often integrated into the display and requires a specific approach. If you are not sure whether your phone has a separate sensor or is built into the matrix, check this in the section "How to find out the type of sensor in your Xiaomi».

We warn you right away that some manipulations (such as disassembling the case or firmware) may take away your warranty if the device is new, and you do everything at your own risk, but in most cases, software is enough to restore the work, and we will consider them first.

How to know if your Xiaomi approximation sensor is in place

Not all Xiaomi models are equipped with a physical proximity sensor. In budget devices (for example, Redmi 9A or POCO C31), its role is often performed by a software algorithm that analyzes data from the accelerometer and gyroscope. In flagships (for example, Xiaomi 14 Ultra), the sensor can be integrated into the display module or located separately above the screen.

To check the presence and type of sensor:

1. Install the AIDA64 app (free on Google Play).
2. Go to the Sensors section.
3. Look at the Proximity sensor line: If you have one, you have a hardware sensor. If you don't have one, but the phone turns off the screen when you call, you use software emulation.

You can also visually view the top of the screen:

• 🔍 Separate sensor: a small circular or rectangular hole next to the speaker (e.g., in the Redmi Note 11).
• 📱 Integrated in display: no visible holes, but the screen reacts to the approach (specific to Xiaomi) 12T newer).
• 🤖 Software emulation: no physical sensors, only algorithms (found in ultra-budget models).

Signs of malfunction of the proximity sensor

The symptoms of sensor failure are often confused with the bugs of the firmware or screen, and here are some clear signs that the problem is with it:

• 📞 The screen does not go out during a call when you hold the phone to your ear (leads to occasional cheek pressings).
• 🔄 The screen spontaneously turns off during normal use (for example, when reading or scrolling tape).
• 🔋 The battery discharges much faster than usual (the sensor is constantly active and consumes energy).
• 🎯 In test applications (e.g. Sensor Test), the sensor shows permanently zero or maximum values regardless of obstacles.
• 🔊 During a bell, the sound switches between the speaker and the tube for no reason.

If any of these symptoms are on a regular basis, the sensor requires a diagnosis, but before you sin on iron, check the software settings:

⚠️ Note: On some models (e.g, POCO X3 Pro) the proximity sensor turns off when the headphones are connected. If the screen does not go out during a call with a wired headset, it is normal!

How to check the proximity sensor on Xiaomi without root

Before you take your phone apart or carry it to the service, you need to do a software diagnostic, and you don't need root rights or special knowledge, you need standard tools and free apps.

Method 1: Built-in test (Engineer Mode)

1. Open the phone app and enter the code: ##6484##
2. Select Proximity Sensor (proximity sensor).
3. Put your hand to the top of the screen: 🟢 If the values change from 5.0 cm to 0.0 cm, the sensor works. 🔴 If the values do not change or show an error, the sensor is defective.

Method 2: Sensor Test (Google Play)

Download and launch the app. Go to the Proximity tab. Normal metrics:

• 📊 No obstacles: 5.0-8.0 cm value (depending on model).
• 🖐️ With obstacle: 0.0 cm or Covered.

Method 3: Checking through ADB (for Advanced)

If the first two methods fail, connect your phone to your PC and follow the command:

adb shell dumpsys sensorservice

In the output, find the Proximity sensor string – there will be current data from the sensor.

The sensor is checked with Engineer Mode

Installed application Sensor Test

Data backup made.

Tried resetting sensor settings

Cleaned the top of the screen from dirt-->

Calibration of the proximity sensor: step-by-step instructions

If the sensor is working but it doesn't respond correctly (e.g., it's going too late or too early), it needs to be recalibrated, and in most cases, this solves the problem without disassembling the phone.

Method 1: Engineer Mode (for MIUI)

1. Enter the code ##36446337## (alternative login to the engineering menu).

Method 2: Proximity Sensor Reset App

This app automatically resets the sensor settings.

1. Open the app and press Reset Proximity Sensor.
2. Wait 10-15 seconds (the phone may freeze for a short time).
3. Reset the device.

Method 3: Manual calibration through files (requires root)

If the first two methods did not help, and root-rights are available, edit the calibration file:

/system/etc/sensors/proximity_calibration.xml

Open it in the text editor and change the min and max values to the standard ones for your model (can be found on the 4PDA or XDA forums).

💡

If after calibration the sensor began to work worse, return the factory settings through Settings → About phone → Reset settings (select “Reset sensor settings”).

What to do if the proximity sensor does not work at all

If the diagnosis showed that the sensor does not respond at all, the reasons may be as follows (from simple to complex):

1. Update MIUI to the latest version or roll back to stable firmware via Fastboot.

Algorithm of action:

1. Clean the sensor and restart the phone.
2. Update the firmware through Settings → About the phone → System update.
3. Reset the sensor settings (see previous section).
4. If nothing helps, take your phone apart and check the plume (instructions for popular models are available on YouTube).

⚠️ Attention: On models with AMOLED-screens (e.g. Xiaomi 13 or Xiao) POCO F4) The sensor is often soldered into the display module, and its replacement requires a complete replacement of the screen!

Replacement of the proximity sensor: when you need and how much it costs

If all the software methods have been tried and the sensor still doesn't work, then there's hardware repair, and the cost and complexity depend on the model.

Where to replace:

• 🔧 Xiaomi official service: warranty 6-12 months, but more expensive by 20-30%.
• 🛠️ Local Service Centers: Cheaper, but Check Reviews and Ask for Guarantee.

For self-replacement, buy a sensor on AliExpress (price - 100-500). ₽) And you can follow the guides for your model, like the Redmi Note 8 Pro:

• Unplug the screen (use suction cups and mediator).
• Disconnect the battery plume (required!).
• Replace the sensor (it is attached to bilateral tape or glue).
• Put the phone back together.

💡

Before replacing the sensor, check if the warranty period has expired! If the phone is warranty, contact the official service - self-repair will cancel it.

Frequent questions about the proximity sensor on Xiaomi