Approximation sensor on Xiaomi Redmi Note 8 Pro: where is located, how it works and what to do in case of malfunction

The proximity sensor is one of those small but critical components that users only remember when it stops working. In the Xiaomi Redmi Note 8 Pro, the module is responsible for automatically turning off the screen during a call, preventing accidental tapping of the cheek or ear. However, its location is not always obvious: the manufacturer does not allocate the sensor on the front panel, and in the documentation information is often minimized.

If you notice that the screen doesn't go out when you hold the phone to your ear, or vice versa, it doesn't turn on when the call is done, it could be the proximity sensor that's the problem. In this article, we're not only going to show you where the proximity sensor is on the Redmi Note 8 Pro, but we're going to explain how to check it, why it's failing, and what to do if you need a replacement. We're going to focus on the nuances of the design of this model, like why the sensor is combined with other sensors and how it affects repairs.

For owners who want to understand the device or fix the problem on their own, we have prepared step-by-step photo instructions, comparison troublesheets and diagnostic tips.

Where is the proximity sensor on Xiaomi Redmi Note 8 Pro: the exact location

In the Redmi Note 8 Pro, the proximity sensor is integrated into the top of the display module, next to the front camera, specifically, it is located under the screen glass, to the left of the speaker (when you look at the phone in the standard position, the screen to yourself), visually it is not visible: on top there is only a small hole for the camera and a slot for the auditory speaker, and the sensor itself is hidden under a black masking film.

Technically, the proximity sensor in this model is an infrared sensor that consists of two elements: an emitter (sends an invisible infrared signal) and a receiver (reflects the signal). When you bring the phone to your ear, the signal reflects off the surface and returns back so the system knows that the screen needs to be turned off. In the Redmi Note 8 Pro, these elements are combined with the light sensor in one module, which makes it difficult to separate them.

To better imagine the location, look at the top of the screen:

• 📱 On the left is a speaker spoken (net with small holes).
• 🕳️ In the center - front camera (hole in the display).
• 🔍 Right of the camera - proximity and illumination sensor (invisible under glass).

Important: In the Redmi Note 8 Pro, the proximity sensor does not have a separate window in the screen windows (unlike some Samsung or iPhone models), so it cannot be seen with the naked eye, which often confuses users when looking for faults.

How the proximity sensor in the Redmi Note 8 Pro: the principle of operation

The proximity sensor in a smartphone is not just a screen switch, it works on the principle of an infrared barrier.

1. The emitter sends an IR ray (invisible to humans).
2. If there is an obstacle nearby (such as your ear), the beam is reflected and returned to the receiver.
3. The microcontroller analyzes the strength of the reflected signal and sends a command to turn off the backlight of the screen.

In the Redmi Note 8 Pro, this process takes a fraction of a second, but there can be delays sometimes – especially if the sensor is hit by dirt or damaged.

And interestingly, the proximity sensor is not only activated during calls, but it's also used:

• 📞 When holding the phone to your ear while listening to voice messages (in some firmware).
• 🎮 In games where the control is carried out by tilting the device (so that the screen does not react to accidental touches).
• 🔋 To save battery power (for example, in the mode "pocket sensor", if supported by firmware).

V MIUI (The sensor is regulated at the system level, for example, if you notice that the screen goes off too early or, conversely, does not respond to the approach, the problem may lie not in the sensor itself, but in the firmware settings or application conflict. We will talk about this in more detail in the section on diagnosis.

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If the proximity sensor is too sensitive (for example, the screen goes out when you normally hold your phone in your hand), try calibrating it through the engineering menu. To do this, dial ##6484## and select "Proximity Sensor".

How to check the proximity sensor for performance

Before you carry your phone to the service center, you should check for yourself whether the sensor is working, here are some ways to diagnose:

1. Visual test through engineering menu

The most reliable method is to use a hidden engineering menu:

1. Open the Phone app and dial ##6484##.
2. Select Proximity Sensor (approximation sensor).
3. A graph or digital value (usually 0 to 5 cm) will appear on the screen.
4. Close the sensor with your hand, the value should change to 0 (or close to it). Remove your hand, the value will return to 5.

If the readings do not change or the schedule is “frozen”, the sensor is defective.

2. Verification through annexes

Google Play has tools for testing sensors, such as:

• 📱 Phone Doctor Plus – shows the status of all sensors, including the approximation.
• 🔍 Sensor Test – displays current values in real time.
• 🛠️ CPU-Z — In the Sensors section you can see data from the sensor.

If the applications show that the sensor is not responding, but it works in the engineering menu, the problem may be in the firmware or software conflict.

Manual check (without software)

Simple test:

1. Call another phone (or use a voice assistant).
2. Hold the Redmi Note 8 Pro to your ear, and the screen should go out.
3. Take the phone away, the screen should turn back on.

If the screen does not turn off or turn on, the sensor is defective or locked at the software level.

1. Check the sensor through the engineering menu

2. make sure that the problem is not the firmware (reboot the phone)

3. Clean the top of the screen of dirt and protective film

4. Check the sensor operation in safe mode (exclude application conflict)-->

Causes of failure of the proximity sensor

The proximity sensor in the Redmi Note 8 Pro can fail for several reasons.

The most common problem is that the sensor is contaminated, for example, if you use a phone without a cover, you can get dust or potassium fat deposits from the skin on the top of the screen, and in some cases, the protective film is to blame: if it is not glued correctly and it covers the sensor area, the signal does not pass.

Another common cause is damage after disassembly. In the Redmi Note 8 Pro, the proximity sensor plume goes along with the screen plume, and if you change the display carelessly, it's easy to damage it, and if the phone stops responding to the approach after repair, it's probably the plume that's the problem.

How to fix the proximity sensor: step-by-step instructions

If the diagnostics show that the sensor is defective, you can try to restore it yourself. Let's look at solutions from simple to complex.

1. Sensor cleaning

Often the problem is solved by a banal cleaning:

1. Turn off the phone.
2. Take a cotton swab dipped in isopropyl alcohol (at least 70%).
3. Gently wipe the top of the screen, especially the area to the left of the speaker.
4. Let the phone dry for 5-10 minutes, then turn on and check the sensor.

⚠️ Warning: Do not use aggressive solvents (acetone, gasoline) - they can damage the oleophobic coating of the screen. Also avoid excess liquid so that it does not get inside the case.

Calibration of the sensor

If the sensor is working but is not working correctly (for example, the screen goes off too early or does not turn back on), calibration will help:

1. Dial in the dial number ##6484##.
2. Select Proximity Sensor.
3. Press Calibrate (if there is one).
4. Follow the instructions on the screen (usually close and open the sensor with your hand several times).

If there is no calibration point, try resetting your phone to factory settings (Settings) → The phone. → Resetting settings).

Checking in safe mode

If the sensor is unstable, the problem may be in the application conflict.

1. Press the power button before the off menu appears.
2. Press and hold the "Switch off" option - a prompt will appear to go to Safe Mode.
3. Confirm and wait for the reboot.
4. Check the sensor in safe mode.

If the sensor is working normally in safe mode, remove the recently installed apps (especially those that requested access to the sensors).

4. Replacement of the sensor or display module

If the sensor is physically damaged (for example, after falling or getting moisture), it will have to be replaced. In the Redmi Note 8 Pro, the proximity sensor is soldered into the display module, so the replacement is only carried out with the screen.

• 💰 Replacement of the display module (with a sensor) - from 3000 to 5 000 rubles.
• 🔧 Replacement of the sensor plume (if possible) - from 1,500 rubles.

Self-replacement is not recommended - there is a high risk of damage to other components (for example, a touchscreen plume).

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In 90% of cases, the proximity sensor problem in the Redmi Note 8 Pro is solved by cleaning or calibration. Physical replacement is only required if mechanical damage or moisture is ingested.

Frequent errors in diagnosis and repair

Many users make the same mistakes when trying to fix the proximity sensor.

• 🔨 Disassemble the phone without experience. In the Redmi Note 8 Pro, the display module is attached to glue, and if you take it off gently, you can damage the plumes or the matrix.
• 💦 Use water or soap solution to clean it, which can cause the sensor contacts to corrosion.
• 📱 Press the screen in the sensor area. Infrared sensor is sensitive to mechanical stresses - high pressure can cause it to fail.
• 🔧 Try to solder the sensor yourself. In this model, it's integrated into a flexible display board, and you need a special tool to replace it.

Another common mistake is ignoring software reasons, like when you update them. MIUI The sensor may stop working due to a bug in the firmware, in which case a rollback to the previous version or waiting for a patch from Xiaomi will help. Before carrying the phone for repair, check the forums (for example, check the forums, 4PDA or XDA Developers – the problem is massive, and there is already a solution.

⚠️ Note: If you notice that the proximity sensor stopped working after installing custom firmware (for example, LineageOS or Pixel Experience), the problem is most likely the lack of drivers. MIUI or search for a compatible kernel.

Alternative ways to control the screen during a call

If the proximity sensor is not working and repairs are delayed, alternative methods can be used temporarily:

• 🔄 Manual lock, press the power button to turn off the backlight when you call.
• 📱 Sensor control applications, such as Proximity Sensor Fix or Sensor Disabler, allow you to emulate the operation of the sensor or turn it off software.
• 🔊 Headset use: When you plug in the headphones, the screen doesn't go out, but it doesn't interfere with the conversation.
• 🤖 Guest settings: In some firmware, you can adjust a gesture (e.g., double tap) to lock the screen.

Note that some sensor emulation applications require root rights, which may deprive you of warranty. If the phone is warranty, you should contact the Xiaomi service center.

You can also try to disable the proximity sensor completely (if it interferes more than it helps).

1. Install Activity Launcher from Google Play.
2. Find the Sensor Test or Engineering Mode.
3. Turn off the Proximity Sensor option (if available).

The disadvantage of this method is that the screen will not go out during calls, but you will get rid of accidental positives.

FAQ: Frequent questions about the proximity sensor in the Redmi Note 8 Pro