How to make the screen go off when talking on Xiaomi Redmi 9C: all ways

Have you noticed that your Xiaomi Redmi 9C screen doesn't turn off when you're calling, even though it used to work fine? Or maybe you just bought a smartphone and want to customize it for yourself? The lack of automatic screen shutdown when you bring your phone to your ear is a common problem that not only irritates but also drains the battery and increases the risk of accidental tapping.

In this article, we’ll look at all the possible reasons why the screen doesn’t go out during a conversation, and offer 5 proven solutions, from basic settings to hidden MIUI features. You’ll learn how to check the proximity sensor, set up screen timeouts, use power saving modes, and even bypass hardware limitations with third-party applications. And if nothing helps, we’ll show you how to diagnose a sensor malfunction and what to do next.

Important: instructions are relevant for Xiaomi Redmi 9C (models M2006C3MG/M2006C3MI) based on MIUI 12-14 and Android 10-12.

Why the screen doesn’t go out during the call: the main reasons

Before you start settings, it is worth figuring out why the Redmi screen is a good idea. 9C It's not acting as expected.-5 Reasons why the automatic shutdown function may not work:

• 🔧 The proximity sensor is off, the most common case. MIUI This feature can be reset after updates or resets.
• ⚙️ Incorrect screen settings: too long timeout or the “Always On Display” mode enabled).
• 📱 Firmware problems: bugs in MIUI after an update or informal build where sensors are unstable.
• 🛠️ Physical damage to the sensor: falls, moisture or dust under the glass can make it fail.
• 🔄 Application conflict: Some programs (such as launchers or optimizers) block sensors.

Fun fact: on the Redmi 9C, the proximity sensor is located to the right of the speaker (if you look at the screen), and it is easy to check manually, as we will discuss in the next section.

How to check the proximity sensor on the Redmi 9C

Before you go through the settings, make sure that the proximity sensor is physically fit, and you don't need any special programs to do that, because standard MIUI tools are enough.

Method 1: through the test mode (hidden menu):

1. Open the Phone app.
2. Enter the combination: ##6484## (or #4636## → “Testing”).
3. Select Proximity Sensor (Proximity Sensor).
4. Close the top of the screen with your hand – the value should change from 5.00 cm to 0.00 cm.

Method 2: through the Engineering Menu (for advanced users):

1. Type in the phone: ##4636##


2 Go to "Hardware testing" → "Sensors."




3. Find the line "Proximity sensor".




4. Close your hand, status should change from "FAR" to "NEAR."

⚠️ Warning: Don't confuse the proximity sensor with the light sensor (which is responsible for automatic brightness). 9C They're located nearby, but they have different functions, and if the test only responds to light, the problem is the proximity sensor.

Method 1: Enabling the proximity sensor in the MIUI settings

The easiest and most effective method is to activate the sensor manually, and in some versions of MIUI, this option is hidden, but it can be found through search or direct paths.

Instructions:

1. Open the Settings → Screen.
2. Scroll down and find the Approach Sensor (or Automatic Screen Shutdown).
3. Activate the switch. If there is no point, search by settings (the magnifying glass icon at the top).
4. For reliability, restart the phone.

Call another phone.|Bring the Redmi. 9C ear-to-ear|The screen should go out in 1-2 seconds.|After removing the screen from the ear, the display lights up again.-->

⚠️ Attention: On some firmware MIUI 13+ The proximity sensor may not be available. In this case, try an alternative path: → Special facilities → Physical buttons → Approximation sensor.

Method 2: Set up screen timeout during a call

If the sensor is on, but the screen is still not going out, the problem may be the screen timeout. By default, the MIUI delay time is 30 seconds, but for calls, this value can be reduced.

How to change it:

1. Go to Settings → Screen → Screen timeout.
2. Select the minimum value of 15 seconds or 30 seconds.
3. For separate calls: open Settings → Apps → Phone → screen timeout and set 5 seconds.

💡 Useful tip: If your firmware doesn’t have a separate timeout for calls, install the Screen Off and Lock app from Google Play.It lets you create rules to automatically turn off the screen under certain conditions (for example, during a call).

Method 3: Use of energy saving mode

There's a hidden feature in MIUI that forcefully shuts down the screen when you call when you're in power saving mode, which is not obvious, but it works for people who don't have the proximity sensor working.

How to activate:

1. Open Settings → Battery and Performance.
2. Select Power Saving Mode.
3. Activate the option to turn off the screen when you lock (if any).
4. Return to Additional Settings → Screen and turn on Adaptive Brightness (sometimes this affects sensor performance).

⚠️ Warning: In power saving mode, notifications from some applications (e.g. messengers) may be turned off. If critical, use this method only temporarily until you find the root cause of the problem.

Alternatively, you can only turn on Super Power Saving for the duration of the call.

• 📞 During the call, swipe down the notification panel.
• 🔋 Click on the battery icon and select Super Mode.
• ⏱️ The screen will go out in 5-10 seconds, even if the sensor is not working.

Method 4: Reset screen settings and sensors

If previous methods have failed, the problem may be a conflict of system settings, in which case resetting screen and sensor settings without losing data will help.

Step-by-step:

1. Open the Settings. → The phone.
2. Click 7 times on the MIUI version to activate the developer mode.
3. Back to Settings → Additionally. → For developers.
4. Find Reset screen settings (or Reset sensors) and confirm the action.
5. Reboot the phone.

💡

After reset, check the sensor through the test menu (#6484##). If the screen still doesn't go out, try rolling back the firmware to the previous version (if the problem has appeared after the update).

⚠️ Warning: Resetting screen settings will return to factory values:

• 🔍 Brightness and color temperature.
• ⏱️ Screen timeout.
• 📱 Gestures and touch buttons.

We recommend pre-recording the current settings (for example, take a picture of the screen).

Method 5: Third-party applications for forced screen shutdown

If hardware isn't working, specialized tools will come to the rescue, mimicking the approach sensor or forcefully locking the screen on a schedule.

Top.-3 supplant 9C:

📌 How to set up Automate for Redmi 9C:

1. Install the application and grant rights to Special Opportunities.
2. Create a new stream: Event → Phone → Incoming / Outgoing call.
3. Add the action: Screen → Turn off the screen.
4. Save and activate the flow.

💡

Third-party applications are a temporary solution. If the sensor is physically defective, the problem may worsen over time (e.g., automatic brightness control will stop working).

What to do if nothing helps: diagnosis and repair

If you've tried all of these, but the Redmi 9C screen still doesn't go out during calls, it's probably a hardware malfunction.

1. Check the integrity of the sensor plume: 🛠️ Disassemble the phone (or contact the service). 🔍 Inspect the plume connecting the sensor to the motherboard. 🔌 If necessary, reconnect it.

Test the sensor with a multimeter:

The nominal resistance of the serviceable sensor is ~10 kΩ in the "long" state and ~0 Ohm in the "near" state.

Replace the sensor:

The cost of a new sensor for Redmi 9C — about 300-500 ₽. Replacement is better to trust the service center.

⚠️ Note: If you decide to replace the sensor yourself, consider:

• 🔧 For the Redmi disassembly 9C you will need a plastic spatula and suction cup - metal tools will damage the body.
• 🔋 Turn off the battery before work to avoid short circuits.
• 📸 Take a picture of the location of the plumes before disconnecting.

💡 Tip: Before repairing, check your phone for hidden damage, for example, if you get moisture, it could oxidize the contacts of the sensor, in which case cleaning with alcohol or replacing the plume will help.

FAQ: Frequent questions about screen settings on Redmi 9C