Here you go. Settings -> Driving Assist -> Driver Support and the very first one on the top is a setting for your proactive driving
Also maybe take a look at Collision Mitigation below and it has setting for Sensitivity as well.
And just look over all the setting you got under Driving Assist, there is settings for dynamic radar etc.

 

i find pda to be a real pain in the patooty. it means that the car slows down, which means you'll arrive at your destination later. and, if the system were truly "smart," the computer would
direct the car to switch lanes to avoid a slow vehicle or slow lane. i use the std. cruise control. much happier driver now!

 

UPDATE: I finally figured out why my PDA wasn't working all the time. If I don't put on my seat belt it doesn't work and the icon on the dash doesn't appear. When I have my seat belt on, it works flawlessly.

 

In my country it's the law to wear your seatbelt.