Disable the proximity sensor on Xiaomi Redmi 9A: Complete guide through the engineering menu

Why users want to disable the proximity sensor and when it is dangerous

Approximate sensor in Xiaomi Redmi 9A — A small but critical component that automatically shuts down the screen during a phone call, but many owners are faced with the incorrect operation of the screen: The screen goes out for no reason, does not respond to the phone's withdrawal from the ear, or, conversely, remains active during the call, which leads to accidental pressing, these failures are especially annoying when using the headset or during games, when the sensor locks the screen mistakenly.

Turning the sensor off via the engineering menu is a radical solution that can both fix the problem and create new ones, for example, after the sensor is deactivated, the screen will remain on while making calls, which increases the risk of clicking buttons with the cheek or ear. In addition, some system functions (e.g., power optimization) may not work properly. 9A firmware MIUI 12+ Disabling the sensor through the engineering menu may reset after restarting or updating the system.

In this article, we will discuss:

• 🔍 Causes of proximity sensor failures and how to diagnose them without turning them off
• 🛠️ Step-by-step access to the engineering menu on Redmi 9A (including codes and alternative methods)
• ⚙️ Menu parameters responsible for the operation of the sensor and their safe values
• ⚠️ Risks and consequences of deactivation, including battery and call effects
• 🔄 Alternative methods (e.g., through ADB third-party)

Signs of malfunctioning of the proximity sensor: how to make sure that the problem is in it

Before you turn off the sensor, make sure it's the fault.

• 📵 The screen goes out when the phone is tilted or covered with a hand (even not during the call).
• 🔦 During a conversation, the screen is not blocked, which causes buttons to be pressed.
• 🔄 The sensor is triggered with a delay (for example, the screen turns on 2-3 seconds after the phone is removed from the ear).
• 📱 Apps (like Google Play’s Sensor Test) show unstable sensor values.

For diagnostics, use the built-in hardware testing:

1. Open the Phone app and type ##6484## (or #4636## → Testing of equipment).
2. Select Sensor Test (also known as Hardware Test).
3. Cover the top of the phone (where the sensor is located) with your hand. the value should change from 5 (no obstacle) to 0 (there is an obstacle).

⚠️ Warning: If the sensor does not respond to the test or shows a constant value 0/5 Regardless of the obstacle, the problem may be a hardware failure (for example, a departed plume or a sensor contamination.

Also check if the sensor is disturbed by a protective glass or cover, for example, thick bumpers or metallic film can block the infrared signal, try to remove the accessories and repeat the test.

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If the sensor is only unstable in certain applications (for example, when calling via WhatsApp), the problem may be in the settings of the specific software. → Annexes → Permits.

How to enter the engineering menu on Xiaomi Redmi 9A: work-in

Engineering Mode – Hidden section MIUI, It's designed for testing and debugging, and it's accessed through secret codes or third-party utilities. 9A the following methods are used:

Method 1: Code for Entry into Engineer Mode

The easiest way to do this is to use USSD-code:

1. Open the standard phone application.
2. Enter the combination: ##36446337## (or alternative code ##4636###).
3. The EngineerMode menu will appear on the screen (it can be called Testing or the EngineerMode menu). MTK Engineer Mode, if the phone is on a MediaTek processor).

Method 2: Through the application MTK Engineering Mode

If the codes don’t work (for example, due to operator restrictions), install the app from Google Play. MTK Engineering Mode:

Download the app from an official source (avoid clones)

Provide all the permissions requested (camera, microphone, sensors)

Close background applications that may block sensor access

Connect your phone to charge (recommended for stability)

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After installation:

1. Open the app and select MTK Settings.
2. Go to the Hardware Testing → Sensor section.
3. Find the Proximity Sensor (approximation sensor).

⚠️ Attention: Some versions MIUI You block access to the engineering menu through third-party applications. If you enter a code or run the utility, you get a Connection problem error, try disabling Mi Cloud and Settings. → Additionally. → For developers → Debugging by USB (if included).

Method 3: Through ADB (for advanced users)

If standard methods do not work, you can use them. ADB (Android Debug Bridge:

1. Turn on Developer Mode: Go to Settings → About Phone and click on MIUI Version 7 times.
2. Return to Settings → Additional → For developers and activate Debugging over USB.
3. Connect your phone to your PC, open the command line and type in: adb shell am start -n com.miui.engineermode/.EngineerMode

Step-by-step: how to disable the proximity sensor in the engineering menu

After successfully logging into Engineer Mode, follow this instruction. 9A The path to sensor settings may differ depending on the version MIUI Processor type (Qualcomm or MediaTek).

For phones running a Qualcomm processor (e.g. Redmi) 9A Snapdragon 439)

1. In the engineering menu, select Hardware Testing.
2. Go to Sensor. → Proximity Sensor.
3. Find the parameter. PS Calibration (calibration of the proximity sensor).
4. Select Disable or set 0 in the field PS Offset.
5. Save the settings and restart the phone.

For phones on the MediaTek processor

1. In the engineering menu, go to MTK Settings → Hardware Testing.
2. Select Sensor. → Proximity Sensor.
3. Find a point. PS Enable and change the value from 1 to 0.
4. In some cases, it may be necessary to disconnect PS Auto Test.

⚠️ Note: After disabling the sensor in the engineering menu, some features MIUI They may not work properly, for example: 📞 During calls, the screen will not be blocked, which will lead to accidental pressing. 🔋 Possible increased battery consumption due to constant screen activity. 📱 Some applications (e.g. banking) may be in error due to lack of sensor data. To get it back, repeat the steps and set a value of 1 to PS Enable.

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Disabling the sensor through the engineering menu is a temporary solution. MIUI The parameters can return to the factory.

Alternative ways to disable the proximity sensor

If the engineering menu is not available or changes are not saved, try other methods:

Method 1: Through ADB (shutdown)

This method requires a PC and enabled debugging on USB:

1. Connect your phone to your computer and open the command line in the ADB folder.
2. Enter the command to check the connection: adb devices (should display the name of your device).
3. Disable the sensor command: adb shell settings put system proximity_sensor_disabled 1
4. Reboot the phone.

To return the sensor back, use the same command with a value of 0.

Method 2: Sensor Disabler application

Google Play has tools that allow you to turn off sensors without root rights, such as Sensor Disabler:

• 📥 Install the application and provide access to Special Features.
• 🔍 In the list of sensors, find Proximity Sensor.
• 🔘 Switch the slider to the Disabled position.

The disadvantage of the method: the application must work in the background, which increases battery consumption.

Method 3: Physical Disconnection (only for power users)

If the sensor breaks physically (for example, after a fall), it can be turned off at the plume level:

What to do if the proximity sensor shuts down on its own

Sometimes the sensor stops working without user intervention.

If the sensor is disabled after installing custom firmware (for example, LineageOS or Pixel Experience), the problem may be the lack of drivers.

1. Install the official firmware through the Mi Flash Tool.
2. Update the kernel or patches for sensors (if available for your firmware).

⚠️ Warning: If the sensor stops working after a phone drop or moisture hits, do not try to turn it on through the engineering menu. This may lead to a short circuit.

The effect of the disconnected sensor on the battery and functionality of the phone

Many users fear that deactivation of the proximity sensor will adversely affect the work of Redmi. 9A. Let's look at the real consequences:

1. Battery consumption

The proximity sensor consumes a minimum amount of energy (about 0.1-0.3% of charge per day), its shutdown will slightly increase the operating time, but the effect will be invisible against the background of other processes (for example, mobile Internet or mobile Internet). GPS). However, if the screen is turned on during calls, the battery consumption will increase.

2. Calls and SMS

The main risk is random tapping during a conversation, such as:

• 📞 You can accidentally put the phone down or turn on the speakerphone.
• 📝 In messengers (WhatsApp, Telegram) can send voice messages or press buttons.

Solution: Use a headset or turn on Airplane Mode when making calls (if you don’t need mobile internet).

3. Operation of the applications

Some programs (such as banking or fitness trackers) check for sensors, and after shutdown, you may experience:

• 🏦 Authorization errors in banking applications (requires to turn the sensor back on).
• 🏃‍♂️ Incorrect operation of pedometers or sleep trackers (if they use data from the proximity sensor to determine the position of the phone).

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Disabling the proximity sensor does not affect the basic functions of the phone (communication, camera, GPS), But it can make you uncomfortable when you call.

FAQ: Frequent questions about shutting down the proximity sensor