Xiaomi smartphone owners often face a situation where the screen goes out on its own during a conversation or, conversely, presses its cheek and drops calls. On the Redmi 8T, this problem is solved not by finding a separate hole on the body, but by understanding the software and front camera. Many users mistakenly search for a physical sensor on the front panel, unaware that in this device it is integrated directly into the camera module or hidden under the display.
Understanding the touchscreen architecture of your gadget is the first step to solving the problem. Unlike older models where the sensor was a separate place at the top, modern technology allows you to save space. If you notice that the Redmi 8T does not lock the screen when you bring it to your ear, it does not always mean a break. Often, simple software calibration through the MIUI engineering menu is enough to return the device to work correctly.
In this article, we will discuss in detail where the touch element is located, how to check its performance without third-party programs, and what to do if the screen behaves unpredictable, you will learn why the security glass can cause failures and how to correctly reset the sensor settings for stable communication.
Location of the sensor: myths and reality
The first thing to know about the Xiaomi Redmi 8T is that it doesn’t have a visible proximity sensor hole next to the speaker, which often baffles users who are used to models with dedicated windows. Engineers have placed the touchpad directly in the area of the front camera, which is in the cutout (drop) at the top of the display.
This is called a virtual sensor, and it uses camera image analysis and infrared light to make the screen bezels thinner, but it's this feature that makes the device sensitive to contamination, and if you're looking for where the proximity sensor is, look at the area around the front camera, which is where the distance data is read.
Sometimes users confuse the light sensor and the proximity sensor. In Redmi 8T, they can be combined into one module or located nearby, but perform different functions. The first adjusts the brightness of the screen, and the second is responsible for locking the display during a conversation. Any of them can malfunction to create the illusion of a breakdown of the entire device.
⚠️ Warning: Do not physically touch the camera area with sharp objects in search of a sensor.You may damage the matrix or plume, which will lead to expensive repairs.
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Use a microfiber to wipe the camera area before every important call – this will eliminate 90% of false alarms.
Checking the performance through the engineering menu
To accurately diagnose the state of hardware components, MIUI has a special engineering menu that allows you to check the response of the sensor without installing unnecessary applications. To get there, open the Phone application and enter the code ##6484#. If the menu does not open, your version of the firmware may require activation through the developer settings.
In the test list that opens, look for a item that might be called "Proximity Sensor" or "Proximity Sensor." Click on it and you'll see two values: current status and threshold. Hold your palm to the top of the screen, closing the camera area. The numbers should change, and the color of the indicator should switch from red to green (or vice versa, depending on the version of the test).
If the values don't change when you put your hand up, it can be a software problem, in which case it helps to reset the device or reset the calibration. If the test shows that the sensor is "closed" even without obstacles, check for a protective film. Thick glass often blocks the infrared radiation necessary for the operation of the infrared sensor.
☑️ Sensor diagnostics
Calibration of the sensor: step-by-step instructions
If the diagnostics show an unstable operation, you need to calibrate, and this procedure retrains the operating system to determine the boundaries of proximity of the object. Go to the settings of your smartphone, select About phone, and click several times on "version". MIUI", The message is, “You’ve become a developer".
Then go to "Advanced Settings" → "For developers. Find the section related to sensor calibration (in some versions). MIUI It's hidden and only available through the engineering menu described above. From the testing menu, select "Proximity Sensor" and press "Calibrate." Put your phone on a flat surface and put your hands away.
Once the process is complete, the system will give a success message, and Redmi 8T will now use the new data to lock the screen, and it's important to do this in good lighting and clean screen surfaces so that the calibration algorithms get the right data.
| Phase | Action. | Expected output |
|---|---|---|
| 1 | Entrance to the menu | Opening of the test list |
| 2 | Choice of test | Activation of Proximity Sensor |
| 3 | Sizing | Resetting values by 0 and 5 |
| 4 | Verification | Stable switching |
Influence of accessories and protective glasses
One of the most common causes of sensor malfunction is poor-quality protective glass, so if the black glass frame is covering the front camera or sensor, the phone will think it's in the ear all the time. Visually, this may be invisible, but for infrared radiation, it's an insurmountable barrier.
Remove the security glass and check the phone without it. If the problem has gone away, you need to pick up an accessory with a notch under the camera or with a thinner black frame, and thick magnetic-clasp bookcases can also be the cause if the magnet is too close to the top end.
Sometimes it helps to glue the glass using a special glue that does not create optical distortion in the area of the sensor. However, if you are not sure of your abilities, you should contact the service. Incorrectly pasted glass can create an air cushion that will also distort the operation of the optical sensor.
⚠️ Attention: Cheap safety glass often has an opaque black bezel that physically locks the sensor.Before buying, check the accessory's compatibility with the Redmi model 8T.
Why is the glass intruding?
Programmatic conflicts and updates
Remember, not only is the hardware responsible for the sensor, but the software code is also responsible. Mistakes in MIUI system updates sometimes cause sensor drivers to crash. If the problem occurs after a firmware update, try clearing the phone and contact cache.
To do this, go to the settings, select Apps, search for Phone, and click Clear Cache. Don't confuse it with Clear All to keep your call history from going down. It's also worth checking for system updates, as Xiaomi often releases patches that fix bugs with sensors.
In some cases, third-party applications that control calls or record conversations cause conflict. Try running your phone in safe mode. If the sensor is working correctly in this mode, then one of the applications you installed is to blame, which intercepts the control of hardware resources.
What to do if the sensor is not working
If neither calibration nor removal of the protective glass helped, there may have been a physical failure of the module. In the Redmi 8T, the sensor is often integrated into the display plume or into a separate small charging plume (depending on the revision of the board), Replacing this component requires disassembling the device.
As a temporary solution, you can use the "Block button" function. In the call settings, enable an option that allows you to lock the screen with the power button, rather than relying on an automatic sensor. This will not eliminate the cause, but will make using the phone during a conversation more comfortable.
If you don't have experience in electronics repair, it's best not to disassemble your phone yourself. Damage to the display plume when disassembled carelessly can cause stripes to appear on the screen or it's completely inoperable. Contact an authorized service for a full hardware diagnostic.
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If software methods and glass removal do not help, the problem lies in the physical damage to the plume or the sensor itself, which requires replacing the part.