For the kit, we use an LED-backlit display which means we can easily adjust the backlight brightness with PWM. You must have the R2 resistor soldered into R2' slot for this to work so make sure you have that and if you can't seem to dim it, double check!
To set the backlight brigness, press the MENU button to enter the configuration menu. Then press MENU four times to get to Set Backlight.
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