Nostromo

Had the B9 for about a year, only twice has it beeped Forward-Pre-Sense at me (with display on dash) when I was driving past some parked cars close to my lane. I assume it thought there could be a collision.

Yesterday had to do a full emergency stop from 45mph when a turn had backed up way down the street. 2 cars in front of me jammed on their brakes, one guy bailed into next lane. B9 slowed down like a champ: big German brakes spitting heat. BMW behind me squeaked once bit but got stopped. The minivan behind him made a horrible shriek but luckily got stopped. ANYHOW: I was suprised Pre-Sense didn't make a peep.

SYMAWD

It senses pedestrians and stopped and slow moving cars traveling the same direction as you when you are going between 10 and 85 kph (~6.2 to 52.7 MPH). If you began braking before the system sensed the situation, no warning was given as you already took control of the situation.

AidanHadley

I'm surprised to read of the higher end of the speed limit. I just double checked it and you're exactly right. But I was recently on the freeway here in Seattle and Pre-Sense activated and seemed to begin to apply the brakes when I momentarily looked away while making a heating adjustment. The traffic had abruptly slowed due to an accident. In that instance I'm sure I had been going faster than that. It really saved my neck that night, beginning to apply the braking much faster than I could.

chemengin

I've been in a situation where pre-sense activated while I was braking, so braking yourself doesn't turn off the emergency braking if needed.

SYMAWD

Yes it will still beep if it thinks you aren't braking hard enough to avoid the danger. It sounds like the OP had already applied 100% braking force.

VM

There are multiple forms of pre-sense - there's pre sense city which is the camera-based system for pedestrian and other obstacle detection. I'm not sure whether that's the same system that does the forward collision warning at highway speeds. (This matters because in different markets, different pre sense systems are included in different packages, e.g. in Canada, you need a Technik with the advanced driver assistance package to get pre sense city)

I will agree with the OP about the outstanding brakes on the B9.

traumeri

I know what you mean about doubting if it's even on, I hope it's because those brakes are really that good so Pre-Sense waits until the last possible split second. I had to turn it to "early" warning just to make sure it works. I've only been daring enough to trigger just the audible part of it when approaching a parked car quickly, but trust that if I was really looking away it would have braked for me. Good to hear that it does work as intended based on others' experiences here!

bob m

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Does pre-sense work in the typical situation that a pedestrian walks out in front of the car or another car backs out of a driveway, while you are driving down the street?

Cornell92

Eli McCraig