Xiaomi Redmi Note 8 Pro is a popular smartphone with automatic brightness control, but many users are faced with the incorrect operation of the light sensor. It can too aggressively dim the screen indoors or, conversely, not respond to changes in light. If you want to completely turn off the light sensor — this article will help to do this in three proven ways.
Unlike most instructions, here we're going to look at not only standard MIUI settings, but also hidden methods through ADB and engineering menus. Importantly, turning off the sensor will lead to manual brightness adjustments, which can affect autonomy. But if you're annoyed by the constant flickering of the screen, this is a justified step.
Why is the light sensor not working properly?
Problems with the light sensor on the Redmi Note 8 Pro are often related to:
- 🔹 Sensor contamination (dust, greasy prints)
- 🔹 Firmware failures (especially after updates) MIUI)
- 🔹 Incorrect calibration in the factory
- 🔹 shell conflict (for example, after installing custom themes)
Before you turn off, try to wipe the sensor (on the right of the front camera) with an alcohol wipe. If that doesn't work, move on to radical measures. Note that on some firmware, the sensor can spontaneously turn on after rebooting. We took this into account in the instructions.
Method 1: Disconnect via standard MIUI settings
The easiest method is to use the built-in options, suitable for MIUI 12, 13 and 14:
- Open the Settings → Display.
- Slap it on Automatic Brightness.
- Move the slider to the off position.
- For reliability, also turn off Adaptive Brightness (if any).
⚠️ Note: On some versions MIUI After the automatic brightness is turned off, the sensor continues to work in the background. To check this, close the sensor with your palm — if the screen is not darkened, then the blackout has worked. If the blackout has occurred, use method 2 or 3.
☑️ Preparation for sensor shutdown
Method 2: Deactivation via ADB (for power users)
If the standard method didn't work, use ADB, the Android debugging tool, which will reliably disable the sensor at the system level.
- 🖥️ Computer with Windows/Linux/macOS
- 🔌 USB-cable (original)
- 📱 Included Debugging by USB (Settings → The phone. → Version. MIUI → 7 times to tap → Developer → Debugging by USB)
Steps:
- Download Platform Tools and unpack.
- Connect the phone to the PC and confirm the debugging permission.
- Open the command line in the adb.exe folder and type:
adb shell settings put system screen_brightness_mode 0This command will force the manual brightness mode to return the automatic mode, use:
adb shell settings put system screen_brightness_mode 1💡 If the sensor is activated again after the reboot, create a task in Automate or Tasker that will automatically execute this command when the phone is turned on.
What if the ADB can’t see the device?
Method 3: Engineering menu (hidden settings)
The Redmi Note 8 Pro has a hidden engineering menu where you can turn off the sensor hardware. Careful: wrong actions here can disrupt the phone.
Instructions:
- Open the Phone app.
- Enter the code ##36446337# MTK-chips, like in the Redmi Note 8 Pro).
- Go to Hardware Testing → Light Sensor.
- Press Disable or reset calibration (Calibration → Reset).
| Parameter | Default value | Recommended value |
|---|---|---|
| Screen brightness mode | 1 (auto) | 0 (handheld) |
| Light sensor calibration | Depends on the firmware. | Reset (dumping) |
| Ambient light lux | Dynamic. | Ignore |
⚠️ Note: Do not change other options, especially those related to Radio or Modem, in the engineering menu, this can lead to network loss or phone buildup. If the screen becomes too dim or bright after the changes, reset the screen settings in the standard settings.
💡
The engineering menu is a powerful tool, but it's dangerous. Use it only if the first two things don't work, and you understand the risks.
What if the sensor turns on after restarting?
This is a common problem on Xiaomi with MIUI 12+ firmware, and it's caused by miui.brightness, which resets settings.
- 📵 Install Shizuku + App Ops and Block the Permission CHANGE_CONFIGURATION system-apply UI.
- 🔄 Create an automatic rule in Tasker that will run ADB-boot-off.
- 🛠️ Reflash your phone to custom firmware (e.g. Pixel Experience) where there are no such bugs.
If you don’t want to go into the settings, the easiest way out is to turn off battery optimization for System UI:
- Go to Settings → Applications → Application Management.
- Put three points on it. → Show system-based.
- Find System UI, open the Battery → Battery Optimization.
- Choose No Limits.
Impact on autonomy: should the sensor be turned off?
Many people fear that manual brightness adjustment will increase battery consumption, and in practice, the difference is minimal:
- 🔋 With automatic brightness, the sensor consumes ~5-10 mA/h (data from AccuBattery).
- 🌡️ When manually adjusted, the flow rate depends on the level selected: 30% brightness ≈ 3-5 mAh.
- ⚡ If you often change the brightness manually, the cost can increase by 1-2% post 8 hours.
Critical: On the Redmi Note 8 Pro, the light sensor is connected to the proximity sensor. When completely disconnected through the engineering menu, you may have problems turning off the screen during calls. ADB-method.