The head unit light control wire marked as "ILL", the color is orange+white.
You need to connect it to your original car light control wire.
Then you can set up dimmer mode through CarMedaiSettings>Backlight control
If you set "Small light control", when you turn on your car lights, the button light will be on, and screen will be dim.
If you set up "Time control", the button light up from 7:00 PM to 7:00 AM, it's off during the day.
You can adjust brightness level through Settings>Display>Brightness level
You can change the color of button light when head unit light is on
If you want to keep button light on all the time, you can connect head unit light control wire on ACC.
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