On many newer Surface devices and some other laptops, the keyboard backlight is controlled by one of the top-row function keys, and the Fn key may need to be toggled first.
- Make sure the Fn layer is set correctly
- On Surface devices, the top row has dual functions (special icons and F1–F12).
- Press the Fn key once to toggle between function mode and special-keys mode (watch for an Fn indicator light if present).
- Try the backlight key
- On newer Surface devices, the F5 key cycles through keyboard backlight levels (off → low → medium → high).
- Press F5 repeatedly (and, if needed, with Fn toggled) to see if the backlight turns on.
- On some older Surface models, F7 is used instead; if F5 does nothing, try F7 in the same way.
- If none of the F-keys work at all
- Check for Windows updates: Start > Settings > Update & Security > Windows Update and install all updates. Missing firmware/driver updates can cause special keys (including backlight) not to function.
- If the keyboard is detachable (Surface Pro Type Cover), ensure it is firmly connected and check for keyboard-specific updates using the Surface app as described in the keyboard troubleshooting article.
- If special keys still do not respond after updates, test with an external keyboard. If the external keyboard works, the built-in keyboard may have a hardware issue and might need service.
If the device is not a Surface, the exact backlight key can differ by manufacturer; in that case, check the laptop’s support page for the specific backlight key and any required keyboard/firmware drivers.
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