Where is the proximity sensor on Xiaomi Redmi Note 8T: circuit, inspection and repair

The Xiaomi Redmi Note 8T is one of the most popular smartphones in the budget segment, but even it can have sensor problems over time. The proximity sensor is responsible for automatically turning off the screen during a call when you hold the phone to your ear. If it fails, the screen does not go out, which leads to accidental pressing and quick battery discharge. In this article, we will analyze where the proximity sensor on the Redmi Note 8T is located, how to check it and what to do if it does not work.

Many users mistakenly search for a sensor in the area of the speaker or front camera, but in fact, its location depends on the model. In the Redmi Note 8T (codename willow), the sensor is integrated into the top of the display, and it is not visible to the naked eye. We will show the exact coordinates, provide photos and explain how to diagnose a malfunction without disassembling the phone.

What is a proximity sensor and why you need it

The proximity sensor is a small electronic module that detects the distance between a smartphone screen and an object (like your ear) and its main function is to turn off the touch screen during a call to avoid accidental touch. Without this sensor, you could press buttons with your cheek or ear, which would cause a call reset or activate other functions.

The Redmi Note 8T uses an infrared (IR) proximity sensor that works by reflecting light, emits an invisible beam and analyzes the signal returning from the object. If the distance is less than a predetermined threshold (usually 2-5 cm), the sensor sends a command to the system to turn off the display.

• 📞 Main task: lock the screen during calls.
• 🔋 Additional feature: battery saving (screen does not shine in vain).
• 🛠️ Frequent problems: the screen does not go out when you call, spontaneous pressing, the sensor is triggered too late.

If the sensor fails, it is not only annoying, but can also cause damage to other components (for example, due to overheating of the screen or unintentional activation of functions).

The exact location of the proximity sensor on the Redmi Note 8T

In the Xiaomi Redmi Note 8T, the proximity sensor is located at the top of the screen, to the right of the front camera, hidden under the display glass and not visible externally, but can be detected by a small hole in the frame (if you look closely).

To identify the sensor accurately, take a flashlight and shine it on the top of the screen, and the proximity sensor will look like a little black dot to the right of the camera, and don't confuse it with a light sensor that's symmetrically on the left.

⚠️ Attention: Do not attempt to pierce the sensor hole with a needle or other sharp object! this can damage the sensor and cause the module to be completely inoperable.

How to check the operation of the proximity sensor

If you suspect that the proximity sensor is faulty, first make sure that the problem is not in the software.

1. Testing through the engineering menu: Dial on the phone keyboard code ##6484## (or ##4636## → “Equipment Testing”). Select Proximity Sensor and put your hand to the top of the screen. If the sensor works, the screen will appear Covered (closed) or 1.
2. App Check: Install Sensor Test or CPU-Z from Google Play. In the Sensors section, find Proximity and check for your hand’s response.
3. Visual test: Call the phone and hold it to your ear. The screen should go out in 1-2 seconds. If it stays on or goes out with a delay, the sensor is faulty.

If the sensor does not respond to any of the actions, the problem may be:

• 🧹 Pollution: Dust or dirt blocks infrared signal.
• 🔧 Train damage: after falling or disassembling the phone.
• 🤖 Firmware failure: Resetting or flashing is required.

Check the reaction in the engineering menu

Install a test application (Sensor Test)

Test during a real call.

Clean the top of the screen from dust

Try restarting your phone.-->

Cleaning the proximity sensor: step-by-step instructions

Most often, the sensor stops working due to the accumulation of dust or fat in the microhole.

1. Preparation: Turn off your phone and take a soft brush (for example, for the camera lens) or a can of compressed air. Don't use wet wipes or alcohol! The liquid can damage the sensor.
2. Clean: Carefully brush the top of the screen, paying attention to the area to the right of the front camera. If you use compressed air, keep the canister at a distance of 10-15 cm.
3. Check: Turn on the phone and retest the sensor through an engineering menu or call.

⚠️ Warning: If the sensor still doesn't work after cleaning, don't try to disassemble the phone yourself! in Redmi Note 8T The propeller sensor is approaching the motherboard, and its replacement requires soldering equipment and experience.

If cleaning doesn’t help, the problem may be:

• 🔌 Oxidation of contacts on the display plume (disassembly is required).
• 🔄 Calibration failure (try resetting to factory settings).
• 🛠️ Physical damage to the sensor (replacement needed).

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If the sensor is working too late, try to increase sensitivity through the engineering menu. To do this, type the code ##36446337## and find the item "Proximity Sensor Calibration".

Calibration of the proximity sensor without root rights

Sometimes the sensor doesn't work properly because of the calibration settings that are wrong, and you can restore them without disassembling the phone.

1. Reset via Engineering Menu: Dial ##6484##, select Proximity Sensor and press Calibrate. After rebooting, check the sensor.
2. Application usage: Install Proximity Sensor Reset from Google Play. The app will reset the sensor settings to factory settings.
3. Manual setting (for advanced): With the help of ADB You can change the trigger threshold. Connect the phone to your PC and execute the command: adb shell settings put system. proximity_delay 1000 where 1000 — delay time.

If the calibration didn't work, it could be a firmware damage, and then you can only flash the phone through the Mi Flash Tool.

Replacement of the proximity sensor: when it is needed and how much it costs

If all the diagnostic and repair methods fail, the proximity sensor will have to be replaced. In the Redmi Note 8T, it is soldered into the motherboard, so replacing it requires:

• 🔧 Thermo-air soldering station.
• 🛒 New sensor (cost) ~300-500 rubles).
• 👨‍🔧 Experience with microelectronics.

Average replacement cost at the service center:

Self-substitution is possible, but it requires care, and if you're not sure about your skills, you should go to the service, and remember, the wrong ration can damage the motherboard, and repairs can cost more.

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If the proximity sensor fails after the phone falls, there is a high probability of damage to the display plume, in which case the entire screen module will need to be replaced (cost ~ 5000-8000 rubles).

Frequent questions about the proximity sensor on the Redmi Note 8T