Just acquired a 2016 W246 for my daughter and from the Data Card I noticed that this car has code 258 ( 258 COLLIS.WARN. SYS. W/ ACTIVE BRAKE INTERV. FCW STOP). Whilst driving on the motorway home, I noticed that a red triangle warning light on the dash when I got to close to the car in front, but the car didn't brake for me. So what exactly is code 258 and how is is a collision warning system with active brake?