The proximity sensor on Xiaomi does not work: reasons and solutions

The proximity sensor in Xiaomi smartphones is a small but critical element responsible for turning off the screen when you hold the phone to your ear, and its malfunction leads to accidental taps, quick battery discharge and discomfort during conversations. According to service centers, up to 15% of calls on Xiaomi Redmi, POCO and Mi are associated with problems of this sensor – and in 80% of cases they can be fixed by yourself.

In this article, we will analyze all possible causes of failure – from software errors to physical damage, as well as give step-by-step instructions for diagnosis and repair. You'll learn how to tell a sensor malfunction from a firmware problem when recalibration is enough and when it takes disassembly. 10/11/12, POCO X3/X4 mi 11/12, where the problem is most often encountered.

How the proximity sensor works and why it breaks

The proximity sensor in Xiaomi is an infrared sensor that emits and picks up the reflected signal. When you hold the phone to your ear, the sensor picks up the obstacle and sends a command to the system to turn off the screen and touchscreen. Modern models (starting with the Redmi Note 9) use a combined module combined with a light sensor.

The main causes of malfunction:

• 📱 Software failures: firmware errors, conflicts after the update MIUI, reset.
• 🔧 Sensor pollution: dust, fat deposits or protective film block infrared signal.
• 💥 Physical injuries: falls, bumps, ingress of moisture (even after "successful" drying).
• 🔋 Wear of components: old models (Redmi) 4/5) sensors can degrade over time.
• 🛠️ Poor repair: After replacing the display or battery, you often forget to connect the sensor plume.

An important nuance for Xiaomi is that in 30% of cases the “failed” sensor is actually functional – the problem lies in the system settings or conflict with the MIUI shell. For example, after upgrading to MIUI 14, many users of the POCO F3 experienced false positives due to an error in the signal processing algorithm.

Diagnosis: How to check the proximity sensor

Before you start repairing, make sure the sensor is the problem. Here are 3 reliable diagnostic methods:

1. Test through the engineering menu

The most accurate method is to check the sensor readings in real time:

1. Open the Phone app and dial ##6484## (for newer versions, MIUI may not work – use the alternative below).
2. Select Proximity Sensor (proximity sensor).
3. Close the sensor with your hand – the value should change from 5.00 cm to 0.00 cm.

If the readings do not change or an error is displayed, the sensor is defective.

Alternative test (for MIUI 12+)

If the code doesn’t work, use this:

Settings → About phone → MIUI version (step 5 times in a row) → Additional settings → Equipment test → Approximation sensor

3. Eye check

Turn on the front camera and shine a flashlight on the sensor area (usually to the right of the speaker).The correct sensor should light slightly red or purple.

Check the sensor through the engineering menu

Make sure the problem isn't with the protective film.

Testing the phone without a cover

Update MIUI last-minute-->

⚠️ Warning: If the sensor responds in the test, but the screen does not go out during the call, the problem is the system settings, not the hardware.

Software solutions: calibration and resetting

In 60 percent of cases, recalibration of the sensor or resetting of the settings solves the problem, and let's start with the simplest methods.

Calibration of the sensor

For models on MIUI 11-14:

1. Go to Settings → System → Additional → Calibration of sensors.
2. Select the Approach Sensor and follow the instructions on the screen (usually close the sensor with your hand for 5 seconds).

If there is no item, use the secret code:

##273282*255*663282*##

2. Reset sensor settings

Open the engineering menu (#36446337##) and select:

• Hardware Testing → Sensor → Proximity Sensor → Reset

3. Firmware update

Sensor bugs are often fixed in MIUI patches. Update the system:

Settings → About the phone → System update

For POCO and global versions of Redmi, check for updates manually – they sometimes get delayed.

⚠️ Warning: After resetting the sensor settings, you may need to restart your phone. If the problem persists, move on to physical cleaning.

Physical cleaning of the sensor: step-by-step instructions

If software methods have failed, the reason may be the sensor contamination, especially for models with screen cutouts (Mi 11, Redmi K40), where dust accumulates into the crevices.

What you need:

• 🧴 Alcohol wipes (70% isopropyl alcohol)
• 🪛 Plastic shoulder blade or toothpick
• 🔦 Lantern (for illumination)
• 🧲 Magnetic screwdriver (for disassembly, if necessary)

Step-by-step process:

1. Turn off the phone and take off the case.
2. Find the sensor – it’s usually located to the right of the front camera (see the photo for your model below).
3. Carefully tuck the protective grate (if any) with a plastic spatula. Don't use metal!
4. Wipe the sensor with an alcohol napkin without pressing. For hard-to-reach areas, use a toothpick wrapped in cotton.
5. Blow the area with compressed air (a balloon or a dryer in cold mode).

After cleaning, check the sensor through the engineering menu. If the problem persists, you may need to replace it.

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For models with OLED-Use an antistatic brush instead of napkins with screens (for example, Mi 11 Ultra) to prevent damage to the matrix.

Replacement of the proximity sensor: when required and how to do

If the sensor does not respond even after cleaning, and the engineering menu displays the Sensor failed error - it must be replaced. The cost of a new sensor for Xiaomi varies from 300 to 1500 rubles depending on the model.

When exactly you need a replacement:

• 🔴 The sensor does not show changes in the test (Proximity Sensor Test).
• 💀 Phone survives falling or contact with water.
• 🔧 After dismantling, physical damage (cracks, oxidation) is visible).

Replacement (for experienced users)

For most Xiaomi models, the algorithm is as follows:

1. Turn off the phone and remove it. SIM-map.
2. Remove the back cover (Redmi Note 10 will require a dryer to soften the adhesive).
3. Disconnect the battery (required!).
4. Find the proximity sensor plume - it goes from the top of the motherboard to the front panel.
5. Gently disconnect the plume and replace the sensor with a new one.
6. Put the phone back together.

Difficulties by model:

• Redmi 9A/9C: The sensor is soldered to the display plume – replacement requires soldering.
• POCO X3: Remove the metal frame, which increases the risk of antenna damage.
• Mi 11: The sensor is integrated into the camera module, changing completely.

⚠️ Attention: On models with IP53 (For example, Redmi Note 11 Pro, after replacing the sensor, the dust protection is broken.

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Replacement of the sensor with Xiaomi AMOLED-screens (Mi 11, Redmi) K50) It is better to trust professionals - the risk of damage to the matrix during disassembly is ~40%.

Frequent Repair Mistakes and How to Avoid Them

Even experienced users make mistakes that can make the problem worse. TOP-5 Failures and How to Prevent Them:

1. Use of metal tools → Solution: only use plastic blades.
2. Neglecting battery shutdown → Solution: Always disconnect the battery before working with the plumes.
3. Clean the sensor with wet wipes → corrosion of contacts. Solution: only use lilac-free wipes with alcohol.
4. Excess force when removing the protective grating → damage to the microphone or speaker. Solution: warm up the edge with a hairdryer (60°C) to soften the glue.
5. Installation of non-original sensor → incompatibility with MIUI. Solution: buy parts only with the Original Xiaomi marking.

Another common mistake is to ignore the check after repair. Always test the sensor through the engineering menu before the phone is finally assembled!

Alternative solutions: if the sensor is not repairable

If the sensor is physically damaged and replacement is not possible (for example, on rare models like the Mi Mix 3), you can use workarounds:

1. Disabling the sensor in the settings

This is a radical method, but it will eliminate random clicks:

Settings → Special features → Physical buttons → Disable the proximity sensor

Cons: the screen will not go out during calls, which increases the risk of pressing the buttons with the cheek.

Applications for sensor emulation

Utilities like Proximity Sensor Fix and Sensor Disabler allow you to:

• 📱 Emulate the sensor’s work by timer (the screen goes out 3 seconds after the start of the call).
• 🔕 Turn off the touchscreen at a certain angle of the phone.

Please note: these applications require ROOT-rights on new versions MIUI.

3. Use of the headset

If the sensor doesn’t work only during calls, go to a Bluetooth headset or wired headphones, in which case the screen will lock automatically when the device is connected.

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Turning off the proximity sensor increases battery consumption by 5-7% due to the constant activity of the screen during calls.

FAQ: Answers to Frequent Questions