MY SON JUST CRASHED MY 2018 AUDI A4 WITH PRE SENSE BASIC AND CITY. $20K DAMAGE IN THE FRONT! NO AIR BAG DEPLOYED. IT HAPPENED ON A HIGHWAY DURING MORNING RUSH HOUR IN HEAVY TRAFFIC. HE WAS DRIVING AROUND 40MPH, TRAFFIC SLOW DOWN AND HE DID NOT REALIZE UNTIL IT WAS TOO LATE. HE BRAKED HARD, BUT THE AUTO BRAKE NEVER KICKED IN.