The problem when the smartphone screen goes out during a conversation and does not light up back, or, conversely, pressed with the cheek to the reset button, is one of the most common for owners of Xiaomi Redmi Note 7. This device, despite its popularity and excellent characteristics, often faces software failures in the sensor located at the top of the case. Users notice that after updating the system or falling device, conversation becomes impossible without using hands-free communication.
The problem lies in the incorrect operation of the proximity sensor, which must instantly respond to objects in the vicinity of the display. In the Redmi Note 7 model, this component often requires manual adjustment of sensitivity values, since factory settings can be knocked down. Fortunately, the MIUI shell provides a hidden engineering mode that allows you to perform accurate calibration without the need to disassemble the device or solder components.
In this article, we will discuss in detail all available methods for restoring the sensor to the special test menu, how to enter the special test menu, what values to change and how to check the result. It is important to understand that software calibration helps only in case of a logical failure, but will not fix a physically damaged module.
Diagnosis of malfunction: symptoms and causes
Before you start to take action, you need to make sure that the problem lies in the sensor, and not in the software freeze system or application conflict. The symptoms of malfunction usually manifest themselves clearly: the screen goes off immediately after you put the phone to your ear, but does not turn on when you move away, or the display burns constantly and the cheek presses unnecessary buttons. Sometimes there is a situation where the top of the screen blackens by several centimeters, blocking control.
The main reason for such failures in the Redmi Note 7 is a software conflict after updating the Android operating system or the MIUI shell. New versions of firmware may misinterpret standard sensor readings, considering the normal distance to the object too close, and protective glasses with a wide black frame that covers the area of operation of the sensor, or banal contamination of the upper part of the case can also have an impact.
For the initial check, you can use a built-in diagnostic tool to see the current state of the sensor in real time, and if you hold your hand to the top of the screen, the value does not change from 5.0 to 0.0 (or vice versa, depending on the version of the test), then the calibration is really broken or the sensor is out of order.
Preparation for calibration: important nuances
The process of adjusting the sensor requires attention and compliance with certain environmental conditions. Before entering the engineering menu, make sure that the Xiaomi Redmi Note 7 screen does not have greasy spots, dust or water droplets in the upper speaker area. Even microscopic pollution can distort the readings of the infrared emitter, which will lead to incorrect calibration.
It's also critical to remove the protective glass or film if they have a darkened frame around the edges. Many owners do not even realize that it is the accessory that blocks the infrared sensor. If after removing the protection, the problem persists, you can switch to software methods. Make sure that the battery is at least 20-30%, although the calibration process consumes minimal energy.
☑️ Redmi Note 7 Preparation for Calibration
Method One: Using CIT's Engineering Menu
The most efficient and safe way to get the sensor back to its correct values is to use the built-in CIT (Customer Integration Test) test menu, which is designed for service centers, but is accessible to any user. To log in, open the Phone app and type in the combination ##6484##. If the code is entered correctly, a list of all device components will open.
In the list you'll find the item that's associated with the proximity sensor. In different versions of MIUI firmware, it can be called differently: "Proximity sensor", "Draw-up Sensor" or simply have a serial number. After selecting the item, a window will open with two main parameters: Max and Min. Your task is to reset the current values to the factory by pressing the "Clear" or "Calibrate" button, and then put the phone on a flat surface without covering the top.
Once you press the calibration button, the system automatically measures the maximum and minimum distance to the object (in this case, the table) and records new odds. The screen can flash or emit an audible signal. If the procedure is successful, you will see a message "Pass" or "Success." Otherwise, if the test is not passed, try repeating the procedure, making sure that there are no objects above the phone, including your hand.
⚠️ Warning: Do not manually press the Pass button unless the test is completed automatically. Forced completion without measurements can fix incorrect values and the problem will have to be solved with a complete reset of settings.
Method Two: Reset via Recovery Menu
If the engineering menu is not working or there is no calibration point, you can try a more radical method, resetting user settings through Recovery mode. This method eliminates software conflicts that may have arisen from errors in the system configuration files. However, remember that this step will delete all your personal data, so backup is mandatory.
To enter Recovery mode, turn off your smartphone completely. Then press the volume button and the power button at the same time. Hold them until the Mi logo appears, then release the power, but keep the volume down. In the menu that appears, select English and go to "Wipe Data."
It is important to select the "Wipe All Data" option to clear the user settings section where the sensor configuration is stored. Once confirmed, the cleaning process will begin, which will take a few minutes. Once completed, the phone will restart as new. In most cases, after initial setup, the system will re-interview the hardware and set the correct sensor values.
What if Recovery doesn’t help?
Comparative table of decision methods
For ease of choice of method of troubleshooting, below is a table comparing the effectiveness and complexity of the described methods. Each option has its own features depending on the specific situation with your device.
| Method | Difficulty | Risk of data loss | Efficiency |
|---|---|---|---|
| Engineering Menu (CIT) | Low. | No. | High (90%) |
| Reset via Recovery | Medium | Total loss. | Medium (70%) |
| Replacement of the module | Tall. | No. | Maximum (in case of breakdown) |
| Third-party annexes | Low. | No. | Low (temporary solution) |
Alternative solutions and third-party software
In cases where Xiaomi’s regular tools don’t help, users often turn to apps from the Google Play Store. There are utilities like Proximity Sensor Reset & Fix or Sensor Test that try to force the driver values to be overwritten. The way they work is similar to the engineering menu, but the algorithms may differ. They can be useful if the standard path is blocked by the manufacturer in a particular version of Android.
However, caution should be exercised when installing third-party software. Some applications require root rights to deeply interfere with the system, which can lead to malfunctioning of banking applications or loss of warranty. In addition, there is a method of disabling the sensor through special commands in the developer menu, but this is only a temporary measure that turns the smartphone into a device where the screen is extinguished only by the power button.
Another option is to use Pocket Mode in lock settings. Sometimes activating or deactivating this option can shake the driver and make it work correctly. Find the Lock and Protect section in the settings and experiment with this option.
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If you use a third-party calibration app, be sure to back up your contacts and photos before you run it, as some may require broad permissions.
Prevention and physical services
After successful calibration, it is important to follow simple rules of operation so that the problem does not return. Regularly wipe the top of the screen, especially the area above the speaker. If you use a case with high sides, make sure that it does not press on the body in the sensor area, creating the illusion of constant approach of the object.
When replacing a display or battery at a service center, always require that the proximity sensor be checked before final assembly. The wizards often forget to calibrate after the plume has been replaced, leading to a re-appearance of the complaint. The physical position of the sensor must be strictly recorded.
Xiaomi periodically releases patches that fix driver errors for the Redmi Note 7. If the problem appeared immediately after the update, it makes sense to wait for the next patch or, conversely, roll back to the previous version of the firmware, if possible.
⚠️ Warning: Use of adhesive or sealant in screen repair in sensor area is strictly prohibited.Adhesive pairs can settle on sensor lens and make it blind forever.
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Software calibration through the engineering menu solves 9 out of 10 sensor problems if it is physically healthy and not contaminated.