Xiaomi approximation module: where is it, how to check and what to do in case of malfunction

The proximity sensor in Xiaomi smartphones is a small but critical component that automatically shuts down the screen during phone calls. When you hold the device to your ear, the proximity module registers the obstacle and extinguishes the backlight, preventing accidental pressing and saving battery power. However, many users face the problem: the sensor sometimes fails, then stops working. The first thing that comes to mind is a physical malfunction of the module. But where exactly is it located in the case of Redmi, POCO or Mi?

In this article, we will not only show the exact location of the proximity sensor in popular Xiaomi models, but also teach you how to check its performance without special tools. You will learn how to distinguish a software failure from a hardware failure, what settings affect the operation of the module, and what to do if the screen does not go out during a call. And for those who are ready for self-repair, we will discuss the dismantling process in detail – from removing the back cover to testing contacts on the board.

Where is the proximity sensor in Xiaomi smartphones

In most Xiaomi models (including the Redmi Note, POCO and Mi series), the approach module is integrated into the top of the display, next to the front camera and speaker.

• 📱 Old models (up to) 2018 year, for example, Redmi 4/5, Mi A1): The sensor is located to the left of the front camera, under the display glass, and can be visually identified by a small circular hole (sometimes disguised as a black dot).
• 📱 Modern models (2019–2023 years, for example, the Redmi Note 10/11, POCO X3/X4): sensor is shifted to the right of the camera or hidden under the display cutout (in models with a "drop-shaped" or "hole" laptop).
• 📱 Flagships (Mi) 11/12, Xiaomi 13): The approach module is often combined with the light sensor in a single chip located under the top frame of the screen.

It's important to understand that the sensor is physically an infrared sensor, consisting of an emitter and a receiver, and it's invisible from the outside because it's hidden under a layer of glass or plastic, and in some models, like the POCO F3, its position is marked by a barely noticeable dot next to the speaker.

How to visually identify the sensor on your Xiaomi

To determine exactly where the approximation module is on your device, follow the following steps:

1. Look at the top of the screen (near the front camera), turn on the flashlight and point the light at an angle, sometimes the sensor will shine through as a small dark spot.
2. Use a magnifier. Some models (like the Redmi 9) have two holes next to the speaker, one for the light sensor, one for the approximation.
3. Compare it to the official diagrams. Xiaomi Service offers disassembled types of popular models with the location of components.

If visual inspection didn't work, try to check the sensor's performance software.

1. Open the Phone app and type ##6484## (test hardware modules).
2. Some firmware has a combination of ##4636## → Phone Information → Sensor Testing.
3. If the test is not available, install the CPU-Z or Sensor Test app from Google Play.

Typical malfunctions of the approximation module and their causes

If the proximity sensor stopped working, the problem could be in the module itself and in the software part.

Critical feature: in Xiaomi models with AMOLED-screens (e.g. Mi 11 Ultra, POCO F4) The proximity sensor is often paired with the light sensor in one chip, and if one of them stops working, the other one can also fail.

⚠️ Warning: If the proximity sensor stopped working after the smartphone crash, don't be in a hurry to change it. Often the problem lies in a disconnected display plume or a microcrack on the board, in which case a full diagnosis at the service center is required.

How to check the proximity sensor without disassembly

Before you carry your phone for repair, try to diagnose the problem yourself. Here are some reliable methods:

• 📞 Test during the call: Call another phone and hold your Xiaomi to your ear. The screen should go out in 0.5-1 second. If it stays on, the sensor doesn't work.
• 🔦 Flashlight check: Turn on the flashlight and point the light at the top of the screen.Some sensors react to bright light as an obstacle (this is normal for older models).
• 📱 Engineering menu: Dial ##6484## → Select Proximity Sensor. Cover the sensor with your finger - the value should change from 5 (no obstacle) to 0 (there is an obstacle).
• 🛠️ Diagnostic apps: Install the Sensor Test or Phone Doctor Plus, and they'll show you if the sensor recognizes and if the sensor readings are correct.

If the sensor does not respond to any of the actions, the problem may be:

• Contamination of glass over the sensor (wipe the screen with alcohol).
• Damage to the display plume (disassembly required).
• Failure of firmware (try to reset the settings to factory).

💡

If the engineering menu doesn't open, try entering the code without the last #. Some Xiaomi models run abbreviated version: #*#6484#

Step-by-step: how to get to the proximity sensor

If you're sure that the problem is a physical malfunction of the module, you can try to replace it yourself.

• Plastic shoulder blades (mediator).
• Screwdriver PH00 or Y00.
• Dryer or thermo-air station (for models with a glued body).
• New approximation module (order using the exact phone model!).

Instructions for most Redmi/POCO models (on the example of Redmi Note 10 Pro):

1. Turn off the phone and remove it. SIM-map.
2. Heat the back cover with a hair dryer (a temperature of ~60°C) for 2-3 minutes to soften the glue.
3. Tap the lid with a plastic spatula, starting at the bottom edge (near the USB-C connector).
4. Unscrew the screws of the mounting of the metal plate covering the battery.
5. Disconnect the battery plume (use a plastic tool!).
6. Remove the display module: unscrew the screws around the perimeter and gently raise the screen (the plumes remain connected!).
7. Find the proximity sensor: it is located on a flexible board next to the front camera (usually glued to a metal frame).
8. Unpold or unplug the old sensor connector and install a new one.

⚠️ Note: In models with a glued display (for example, Mi 11 Lite), an attempt to replace the proximity sensor on your own often results in damage. OLED-In such cases, it is recommended to contact the service.

Software Ways to Solve Sensor Problems

In 60 percent of cases, the proximity sensor malfunction is not caused by hardware failure, but by software failure.

• 🔄 Reset sensor settings: Go to Settings → System system → Additionally. → Setting reset. Select Sensor Reset (if any). Reset your phone.

Calibration through the engineering menu:

Type ##6484## → Proximity Sensor → Calibration

Follow the instructions on the screen (usually cover and open the sensor several times).

Disengagement of gestures:

MIUI

Settings → Screen → Gestures

Firmware update:

Settings → About the phone → System update

MIUI

If the problem has occurred after the update, try to roll back to the previous version of the software via the Mi Flash Tool. Downgrade instructions can be found on the 4PDA or XDA Developers forums.

💡

Before resetting the sensor settings, back up the data. In some firmware, the reset also resets the screen and sound settings.

Frequent questions about the proximity sensor in Xiaomi