Before the High Sierra update, when I used to boot my Macbook Air, the keyboard backlight was always off by default. However, after the update, upon booting the backlight is always on. This is irksome because I always work in a well-lit environment and don't need the backlight. So I have to turn it off each time after start-up. I can't find out how to change this default setting. Can someone help?
Keyboard backlight is on by default after High Sierra update
high sierrakeyboard
Related Solutions
I don't know if it's Lion or a hardware feature, but on my MacBook Air, the system changes the keyboard lighting (and screen brightness) depending on the ambient brightness, which is detected by a sensor near the iSight lens at the top of the screen. In bright surroundings, the keyboard lighting is disabled and pressing F5 or F6 does nothing.
gentmatt’s answer seems useful!
Alternatively, you could try going to System Preferences → Keyboard, and unchecking the “Automatically illuminate keyboard in low light” setting. That should prevent the “disabled” icon from your screenshot altogether.
Best Answer
Go to your system preferences (not sure if that's the exact name in English version of MacOS as I'm looking at the Dutch translation) > keyboard > disable "adjust keyboard backlight in low light environment" (or English words to that effect, it is next to a checkbox).