Make ELK f-key blink


I have a non-alarm door sensor on my garage door. How can I make the f4 key blink if that sensor is showing the door open?
Ahh, I have the keypad in the master bedroom to turn the backlight off after 60-seconds and it also turns the F-key off. Is there a way to have the backlight come on and/or the F-key flash only when the garage door is open? It works if I push a button and turn the backlight off...