Xiaomi Mi 9C NFC (also known as Redmi 9C in some regions) is a budget smartphone with a good set of features, but its proximity sensor sometimes causes inconvenience. Users complain of spontaneously turning off the screen during calls, false positives when using cases or even a complete sensor failure. If you encounter such problems, this article will help to completely disable the sensor or temporarily bypass its incorrect operation.
It's important to understand that the proximity sensor is responsible for automatically turning off the screen when you hold the phone to your ear, preventing accidental tapping during a conversation. Deactivating it can lead to inconveniences, such as accidentally pressing buttons with your cheek. However, in some cases (for example, when the sensor is damaged hardware), turning off is the only way out.
We will look at 5 working methods: from standard settings MIUI before using the engineering menu and ADB-We also discuss how to check the sensor's performance and what to do if it's faulty. If you're not sure about your technical skills, start with the simplest ways (sections 2-3) and then move on to the advanced ones (sections 4-6).
1.Why is the proximity sensor on the Xiaomi 9C NFC not working properly?
Before you turn off the sensor, you should understand the reasons for its malfunction, most often problems are associated with:
- 📱 Sensor pollution -- dust, fat, or protective film can block the infrared signal. 9C NFC Located to the right of the speaker (see photo below).
- 🛠️ Damage after a fall – even a minor impact can shift the optics of the sensor.
- 🔄 Firmware failure – especially after updates MIUI (for example, transition MIUI 12 on MIUI 13).
- 📦 Incompatible cover – too thick or metallized covers block the signal.
If the sensor is triggered chaotically (for example, the screen goes out when you normally hold the phone in your hand), try first to wipe the sensor area with an alcohol wipe and remove the case. If this does not help, move to disconnect.
Method 2: Disconnect via MIUI settings (without root)
The easiest method is to use the built-in MIUI options. Unfortunately, there is no direct option in the standard settings of the Xiaomi 9C NFC to turn off the sensor, but you can get around this through the visually impaired mode:
- Open the Settings. → Special facilities.
- Select Gesture Control (or Physical buttons, depending on the MIUI version).
- Activate the option to Ignore the proximity sensor (in some firmware it is called Turn off the sensor when calling).
- Reboot the phone.
If this option is not available, try an alternative route:
- 🔧 Go to Settings. → System and device → Additionally. → Developer mode.
- 🔍 Turn on Debugging. USB and find the item Disable sensors (if available).
☑️ Preparation for sensor shutdown
Method limitation: Some versions of MIUI 12.5+ may not have these options, so move on to the next method.
Method 2: Use of the engineering menu (#6484##)
The hidden engineering menu allows you to test and customize the hardware components of the smartphone, including the proximity sensor. For the Xiaomi 9C NFC, the order of action is as follows:
- Open the phone app and enter the combination: ##6484###
- Select Proximity Sensor (Proximity Sensor).
- In the window that opens, press Disable.
- Confirm the action and restart the phone.
If the combination doesn’t work, try alternative codes for Xiaomi:
- 📞 ##4636## → Testing of equipment → Sensors.
- 📱 ##36446337## (for some versions) MIUI).
What to do if the engineering menu is not opened?
⚠️ Warning: Do not change other options in the engineering menu without understanding their purpose! this can lead to unstable phone operation or loss of communication.
Method 3: Disconnect via applications (without root)
If the standard methods did not work, you can use third-party utilities. For Xiaomi 9C NFC will suit:
| Annex | Functional | Link (Google Play) | Need root? |
|---|---|---|---|
| Proximity Sensor Reset | Resetting sensor calibration | Reference | No. |
| Sensor Disabler | Temporary shutdown of the sensor | Reference | No. |
| QuickShortcutMaker | Creating a deactivation label | Reference | No. |
Instructions for Sensor Disabler:
- Install the application and provide access to Special Features.
- Select Proximity Sensor from the sensor list.
- Press Disable and confirm the action.
💡
If the screen does not go out during calls after the sensor is turned off, use the lock button manually or turn on the "Raise to wake up" function in the screen settings.
Warning: Some applications may require ADB-access or display ads. Check reviews on Google Play before installing.
5. Method 4: Disconnect via ADB (for advanced users)
If the previous methods have not worked, it remains ADB-The command is a universal way to disable the sensor at the system level:
- 🖥️ Computer with installed ADB-driver.
- 📱 Included Debugging by USB on the phone (Settings) → The phone. → Version. MIUI → 7 times press to unlock the developer mode).
- 🔌 USB-cable (preferably original).
Step-by-step:
- Connect the Xiaomi 9C NFC to your computer and confirm access for debugging.
- Open the command line (Win) + R → Enter cmd) and execute: adb shell settings put global proximity_sensor_disabled 1
- Reboot your phone: adb reboot
To turn the sensor back on, use the command:
adb shell settings put global proximity_sensor_disabled 0⚠️ Attention: After update MIUI setting ADB Repeat the procedure if the sensor is triggered again.
💡
ADB-This is the most reliable method, but it requires a PC connection. If you don't have a computer, use the applications in Section 4.
Method 5: Complete root shutdown (Magisk)
If you are ready for radical measures and have root rights (installed by Magisk), you can disable the sensor at the kernel level.This method is suitable for the Xiaomi 9C NFC with an unlocked bootloader.
Instructions:
- Install Magisk and Sensor Disabler.
- Go to Magisk → Modules and activate the module.
- In /system/usr/idc/*.idc (opened via Root Explorer), find the line: touch.proximity.enable=1 and replace 1 by 0.
- Reboot the phone.
Risks of the method:
- 🚨 Loss of warranty (if the bootloader was unlocked).
- 🔄 Possible failures in the operation of other sensors (gyroscope, accelerometer).
- 📉 Increased battery consumption (the system will constantly poll the disconnected sensor).
7.What to do if the sensor is faulty?
If neither method worked, it could be that the sensor is physically damaged, and you can check this with the CPU-Z or Sensor Test app (available on Google Play).
- 📉 The sensor always shows a value of 0 cm or 5 cm (does not change when you put your hand up).
- 🔄 The screen is turned off / on chaoticly, without communication with the approach.
- 🛠️ A notification appears on the screen saying "The proximity sensor is not responding".
In this case, there are two options:
- Replacement of sensor in the service center (cost) ~1 500–2 500 ₽). Xiaomi. 9C NFC The sensor is assembled with the front camera, so you will have to change the module entirely.
- Using a phone without a sensor with functions disabled (as described above).
If the phone is warranty, contact the official Xiaomi service. Otherwise, look for proven workshops with good reviews.