In a dim room, open System Settings > Keyboard and raise Keyboard brightness. If the keys light up and then go dark while you are away, check the inactivity timer. If the backlight behaves differently as the room lighting changes, check the automatic low-light setting.
01Use the slider to test the built-in keyboard
Section linkFrom the Apple menu, choose System Settings, then Keyboard. Raise the Keyboard brightness slider while looking at the keys. If your model has dedicated keyboard brightness keys, you can use them too. A screen brightness key changes the display, so use the Keyboard slider if you are unsure.
02Check the automatic setting and the sensor
Section linkLook for Adjust keyboard brightness in low light in Keyboard settings. Test the backlight in a dim room with the area near the camera uncovered. That is where Apple places the light sensor. If you prefer a manual level, turn off automatic adjustment and set the slider again.
03Check when the light goes out
Section linkIf the light goes out after you stop typing and comes back when you use the Mac, open Turn keyboard backlight off after inactivity and choose a longer interval. If you cannot find a brightness control, check whether the keyboard has backlighting. If the built-in backlit keyboard stays dark even with the slider raised in a dim room, record your MacBook model and the settings you tried before contacting Apple Support.