The situation of a screen spontaneously turning on while a phone conversation on a Xiaomi or Redmi smartphone is familiar to many users.It is not just a minor inconvenience, but a serious problem that often leads to accidental button pressing, turn on the hands-free communication or, worst of all, to the end of the call with the cheek. The proximity sensor responsible for quenching the display can work incorrectly due to software failure, contamination or improper calibration.
Most of the time, the solution lies in settings for MIUI or HyperOS, which allow for flexible sensor behavior management, but sometimes more in-depth interventions are required, such as resetting the phone app or even using an engineering menu to fine-tune the sensitivity, and understanding the causes of this malfunction will help avoid unnecessary trips to the service center.
In this article, we will take a look at all the methods that are available to fix the problem, how to calibrate the sensor correctly, where to find hidden settings in the engineering menu, and what to do if the screen stops dimming after the system update. Accuracy of execution of instructions is key here, as improper calibration can make things worse.
The main reasons for the incorrect operation of the approximation sensor
Before you start to act, you need to understand the nature of the failure. The proximity sensor is an infrared sensor located at the top of the screen, usually next to a conversational speaker, whose job is to determine the distance to the object (your ear) and send a signal to the system to turn off the touchscreen. If this mechanism fails, the screen continues to respond to touch.
One of the most common causes is banal pollution: Fat spots, dust or residues of a protective film at the top of the display can block the IR radiation, which makes the smartphone “think” that it is still away from the ear, and problems can occur after the device falls, when the physical position of the sensor is disturbed or the plume departs.
Software conflicts are the second most common cause: After upgrading MIUI or installing a new launcher, energy saving settings can aggressively kill the processes that control the sensor, and some third-party applications that have access to the phone can intercept the sensor.
⚠️ Note: If the problem appeared immediately after the replacement of the screen or glass in the service center, most likely, the masters used a poor-quality analogue of the sensor or poorly glued the module.
It's important to distinguish between a temporary software glitch and a hardware failure: If the screen goes out but immediately lights up again without you acting, or if it doesn't respond to a hand at all, these are different scenarios. Hardware malfunctions often require a module replacement, whereas software can be fixed by resetting.
Basic configuration and verification of “pocket mode”
The first step in diagnosing and solving the problem is to check the standard interface settings. In the shell of Xiaomi, there is a feature that directly affects the behavior of the screen during calls, called Pocket mode, and its work is closely related to the proximity sensor.
To access these settings, you need to open the main menu and go to the settings section. The path may vary slightly depending on the Android version, but the logic remains the same. Find the lock and protect item and make sure the switch is activated.
☑️ Checking screen settings
If the function is on but the screen is still not going out, try turning it off and back on again. This action will force the corresponding system process to restart. In some cases, cleaning the Settings app cache through the application management menu helps.
Also worth paying attention to is the design theme. Some third-party themes downloaded from Themes store may have conflicts with standard system features. If you've recently changed the visual style of the interface, try switching to a standard Classic or Default theme and checking the sensor's performance.
Calibration of the proximity sensor through the engineering menu
The most effective way to solve the problem is to manually calibrate the sensor, and Redmi and Xiaomi have a dedicated engineering menu available through standard dialing, which allows the system to learn how to correctly determine distances.
To enter the test mode, open the Phone app and enter a special code. Most devices use the combination ##6484##. Once you enter the last digit, the menu will open automatically. If the code does not work, your firmware version may block this access, and then you will have to look for alternative ways.
In the CIT menu that opens, you need to find a point associated with the proximity sensor, which can be called Proximity Sensor, Approximation Sensor, or just Sensor. Choose this item and follow the instructions on the screen, and you usually need to close the top of the screen with your hand and then remove it.
The calibration process is as follows:
- 📱 Click the Start or Start button to start the test.
- ✋ Close the sensor with your palm until the indicator is green (distance value should change).
- ☀️ Remove your hand, making sure the value has returned to its original state (usually 5.0 cm or more).
- 💾 Click on “Pass” or “Save” to capture new options.
⚠️ Note: During calibration, do not use protective glass with a black frame that covers the sensor, otherwise you will calibrate the smartphone to work with an obstacle, and in reality it will behave incorrectly.
Once the procedure is completed, be sure to restart the device, and reboot is necessary to ensure that the new sensitivity values are applied at the kernel level of the system, without this step, the changes may not take effect.
What if the code doesn't work?
Resetting the phone application data and cleaning the cache
Sometimes the problem isn't the hardware itself, but the accumulated debris or erroneous data in the application that handles the calls. In Android, the standard Dialer app is responsible for this, and reprogramming it often solves the problem of a hanging sensor.
To reset, go to Settings → Apps → All apps. Find the Phone app (it may have a Google or Mi log) on the list. Inside the app menu, you are interested in the Clean button or Delete Data button. It is important to choose to delete data, not just clean the cache.
This operation is safe for your contacts and call history if they are synced with your Google or Mi Cloud account. However, just in case, it is recommended to back up important numbers before the procedure.
| Action. | Impact on data | Need for a reset |
|---|---|---|
| Clearing the cache | Securely, deletes temporary files | Not necessarily. |
| Clearing the data | Resets the call settings, the story remains | Recommended |
| Removal of updates | Returns the factory version of the app | Required. |
If simple methods didn’t work, you can try removing updates to the Phone app. To do so, click on the three dots in the top right corner and select “Delete Updates” on the same menu, and then the phone will return to the factory version of the call, which often eliminates bugs that appeared after the recent update.
Use of third-party applications for calibration
If the built-in MIUI tools don’t work, Google Play offers more tools for sensor testing and deep calibration that is not available on the standard menu.
One of the most popular and reliable tools is the Proximity Sensor Reset & Test app, which automatically determines the model of your device and offers the optimal calibration algorithm. The interface is simple: you close the sensor, the application fixes the minimum value, then opens - fixes the maximum.
Another useful tool is the Sensor Box for Android, which not only calibrates, but also shows detailed graphs of all sensors in real time, and it can see if the sensor readings are twitching or just frozen at one mark, which helps diagnose a hardware problem.
When using third-party software, it is important to follow the following rules:
- 📥 Download apps only from the official Google Play Store to avoid viruses.
- 🔋 During calibration, make sure the battery is over 20%.
- 🚫 Do not install multiple applications at the same time, they may conflict with each other.
After calibrating with third-party software, be sure to reboot your smartphone completely. Restart the system will fix new sensitivity thresholds in the Android registry. Without this step, the application can work correctly in test mode, but behave in the old way in a normal call.
Hardware problems and the impact of accessories
Physical factors can't be discounted either. Very often, the screen doesn't go out because it's not a suitable protective glass or case. If the black glass frame covers the sensor area (even partially), the infrared radiation reflects off the glass, and the phone thinks it's being held up to the ear when it's not, or vice versa, sees no obstruction.
Try removing the cover and temporarily unplug the top edge of the protective glass (if possible) during the test call, if the problem is gone, then it is the accessories, in which case only replacing the glass with a model with a cutout for the sensor or a case with thinner sides will help.
It's also worth checking for moisture or condensation in the upper speaker area, and getting water can close the sensor contacts or create an optical lens that distorts the readings. If the phone has recently come into contact with water, put it in a silica gel container for 24 hours.
💡
Use a transparent sticker on the top of the screen to check, and if the sensor is working under it and it's not working under the black glass, the accessory's light transmission is a problem.
In rare cases, the sensor may be physically displaced inside the body due to impact. If you drop the phone and then problems begin, the software calibration may have a temporary effect, in which case you will need to disassemble the device and correct the plume or replace the module in the service center.
⚠️ Warning: Trying to disassemble your phone yourself to correct the sensor plume takes away your warranty.
Frequently Asked Questions (FAQ)
Why does the screen go out on its own, even when I don’t have my phone to my ear?
Can a MIUI update break the proximity sensor?
Will resetting to factory settings help if the sensor isn't working?
Does the “In Pocket” mode affect regular calls?
💡
In 90% of cases, the problem is solved by correct calibration through an engineering menu or replacing a poor-quality protective glass.