How to find the proximity sensor on Xiaomi Redmi: location, check and troubleshooting

The proximity sensor in Xiaomi Redmi smartphones is a small but critical component that is responsible for turning off the screen when you hold the phone to your ear. Its malfunction leads to accidental pressing, rapid battery discharge and discomfort when talking. However, finding this sensor on the board or device body is not so easy: it is often hidden under protective films, glue or integrated into other modules.

If your Redmi is not responding properly to an ear approach, don’t rush to carry it into service. 80% of the time, the problem is solved by yourself – just know where the sensor is in your model and how to check it. In this article, we will analyze the exact location of the sensor on popular Redmi models (from Note 5 to Note 12 Pro+), learn how to diagnose problems and give recommendations for repair.

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What is a proximity sensor and how does it work

The proximity sensor is an infrared sensor that detects the distance between a smartphone screen and an object (like your ear).

• 🔦 Infrared emitter emits invisible light.
• 👁️ Photodiode – captures the reflected signal and converts it into an electrical pulse.

When you hold the phone to your ear, the reflected IR signal changes intensity, and the system locks the screen, preventing accidental touches. On Xiaomi Redmi, this sensor is usually integrated into the top of the display module, next to the front camera or speaker.

The sensor works in tandem with the software, and failures can occur due to both physical damage (dust, moisture, cracks in the glass) and software errors (for example, after the MIUI update).

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If the sensor stopped working after the phone fell, first check the integrity of the glass around the front camera - even microcracks can block the IR signal.

Where exactly is the proximity sensor on Xiaomi Redmi

The location of the sensor depends on the model of the smartphone. Below we have shown the diagrams for the most popular lines of Redmi, but remember: even within the same series, the position may slightly differ (for example, the Redmi Note 10 Pro and Redmi Note 10S).

To accurately identify the sensor on your model, use one of these methods:

• 🔍 Visual inspection: Hold your phone to a bright lamp and look at the top of the screen at an angle.The sensor usually looks like a tiny black spot (3-5 mm in diameter) next to the camera.
• 📱 Test mode: enter the code ##6484## in the app "Phone" → Choose Proximity Sensor → If you put your hand on the sensor, if it's going from 5 to 0, it's working.
• 🛠️ Disassembly: on models with removable back cover (for example, Redmi) 4X) sensor is visible immediately after removing the panel - it is soldered to the plume of the display.

⚠️ Note: Some models (e.g. Redmi Note 11 Pro)+) The proximity sensor is combined with the light sensor in one chip, so if both sensors stop working after the display is replaced, the problem is the plume or the firmware.

How to check the operability of the sensor of approach

Before you disassemble the phone, make sure the sensor is the problem. Here is a step-by-step diagnostic manual:

1. Open the Phone app and dial ##4636##.
2. In the test menu, select Usage statistics → Sensor test.
3. Find the Proximity sensor bar and cover the top of the phone with your hand. The value should change from 5.0 (no obstacle) to 0.0 (there is an obstacle).
4. If the values do not change, try restarting the phone and repeating the test.

An alternative way is to use apps from Google Play, such as:

• 📊 Phone Tester – Shows the status of all sensors in real time.
• 🔧 Sensor Box for Android – visualizes data from the proximity sensor with a graph.
• 🛠️ CPU-Z — Sensors displays current readings.

Check the sensor response in the engineering menu | Make sure there is no protective film or glass on the screen | Test the sensor in a third-party application (e.g. Sensor Box) | Try calibrating the sensor through the MIUI-->

If the sensor does not respond in any of the tests, the reasons may be as follows:

• 💥 Physical damage: crack on glass, moisture ingress, oxidation of contacts.
• 🔌 Problems with the plume: after replacing the display, the plume may have been damaged or improperly connected.
• 🤖 Software failure: a firmware error MIUI or conflict with the application (for example, after updating).

Display replacements|Phone drop/hit|Updates MIUI|Moisture intrusion|Other causes-->

Why the proximity sensor fails: top-5 cause

Analysis of service centers shows that in 90% of cases, the malfunction of the proximity sensor on Xiaomi Redmi is due to one of these reasons:

1. Replacement of the display in the informal service: Cheap Chinese screens often go without the original proximity sensor (it just doesn't solder to the plume), as a result, the phone "can't see" the sensor, and the screen does not lock during the call.
2. It's got moisture or dust, and it's close to the speaker, and if the phone's been in water or been in a dusty place for a long time, it can get contaminated, and it can cause false positives or a complete failure.
3. Update MIUI: After major updates (for example, from MIUI 12 to MIUI 13), sensor settings can be lost, especially for Redmi Note 8/9 models.
4. Mechanical damage: A hit on the top edge of the phone (where the front camera is located) often results in the sensor detaching from the board or damage to its contacts.
5. Wearing of protective glass: On older models (for example, Redmi 4X or Redmi 5), the protective coating over the sensor becomes cloudy, which worsens the passage of the IR signal.

Critical information: On Redmi Note 10 Pro and later, the proximity sensor is often integrated into a single touch hub, along with an accelerometer and a gyroscope. If several sensors stop working after a fall, the entire module, not just the proximity sensor, needs to be replaced.

⚠️ Attention: If the sensor starts to fire arbitrarily (for example, the screen goes out for no reason while scrolling the tape), the problem may be overheating of the processor. AIDA64.

How to fix the proximity sensor yourself

If the diagnosis confirmed a sensor malfunction, try the following steps (from simple to complex):

1. Software methods (without disassembly)

• 🔄 Reboot: Sometimes the sensor freezes due to an OS error. Just restart the phone.
• 📲 Resetting settings: go to Settings → System system → Additionally. → Reset settings and select Reset all settings (app data will be saved).
• 🛠️ Calibration: From the Engineering Menu (#6484##) select Proximity Sensor Calibration and follow the instructions.

2. mechanical cleaning (for experienced users)

If the sensor is contaminated, it can be cleaned carefully:

1. Remove the back cover (on removable battery models, such as the Redmi 3S).
2. Find the sensor on the display plume (usually marked as PS or PROX).
3. Wet the cotton swab in isopropyl alcohol (at least 90%) and gently wipe the sensor lens.
4. Let the phone dry for 10-15 minutes before assembly.

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Never use acetone or household detergents to clean the sensor – they destroy the protective coating of the lens!

3. Replacement of sensor or plume

If the sensor is physically damaged, it's going to have to be replaced.

• 🛒 Buy the original plume with a sensor (for example, for the Redmi Note). 9 Pro's fine art. MB11-00009).
• 🔧 Take the phone apart, unplug the old plume, and install a new one. On non-removable battery models like the Redmi Note 11, you'll need a special suction cup to take the screen off.
• 🔌 Connect the battery and check the operability of the sensor in the engineering menu.

⚠️ Note: Xiaomi Redmi with AMOLED-screens (e.g. Redmi) K40) The proximity sensor is often soldered into the display module, and in this case, you have to change the entire screen, not just the sensor.

Frequent errors in the repair of the proximity sensor

Even experienced users make mistakes that can make the problem worse.

• 🔥 Use a dryer for drying: high temperatures will damage the plumes and glue holding the screen.
• 🧲 Apply metal tools to clean the sensor – they scratch the lens and can close the contacts.
• 🔋 Disassembling a phone with the battery on: it's a risk of short circuit. Always turn off the battery before work!
• 📱 Install non-original plumes: cheap analogues are often incompatible with firmware MIUI It can cause errors in the operation of other sensors.

Another common mistake is to build the wrong sensor after you change the sensor, for example, if you forget to plug in the speaker plume (which is in the same unit as the sensor on some models), the phone will work, but the proximity sensor will not.

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Before disassembling Xiaomi Redmi always check if it does not have a warranty. Self-repair voids warranty obligations!

Xiaomi Redmi models with frequent proximity sensor problems

Some Redmi models are more prone to proximity sensor malfunctions due to design features, and here is a list of "problem" devices and their typical symptoms:

If your model is on this list, first try software solutions (reset, calibration), and then start disassembling.

FAQ: Frequent questions about the proximity sensor on Xiaomi Redmi