Chuckman

I bought a new '17 C63 AMG Cabriolet last week. Since then I've been hoping to experience indications that the vehicle's Collision Prevention Assist Plus/Brake Assist System features are engaging. I've not noticed any braking assistance, no visual or auditory alerts, nothing. I've checked the vehicle's settings and the braking assist feature is enabled. I've purposely come up a bit fast on cars stopped ahead of me, just to see if that would trigger any alerts, or braking assistance. Nothing has happened. I've also tried engaging the cruise control feature, just to see if it would work then. Nothing is seemingly happening. I don't want to become a crash test dummy trying to troubleshoot this, so is there any way I can check some setting on the vehicle, before having to schedule a service appointment with MB? I've asked my salesman about this a couple of times, but he's had very little to say, other than make an appointment.

RedGray

Great technical question! :-)

Summary:
From what I could quickly find through Google on how dealers show off anti-collision systems to car buyers, they seem to drive them into a foam wall.

Note, a free standing foam wall that is tall enough, wide enough, thick enough, and made with the correct type/treated foam is likely good enough to test most anti-collision systems today.



More Detail:
It also gets into very complicated, and often system/year/model specific features.

A few things:

Depending on the very specific anti-collision system (model/year/features), it's often:
hard, impossible, or not safe for a typical person to properly test an anti-collision feature.


Trying to test the anti-collision system by driving into a wall of balloons (acting like a car) is questionable at best.

Cardboard often works better. But, it's not guaranteed to work.
But, *I* would never drive my car into a bunch of cardboard boxes to see if the anti-collision feature works or not.


Again, depending on the very specific anti-collision system (model/year/features), there may not be a warning or any indication until there is near zero time left for the car/vehicle to brake.

Also, anti-collision are not perfect. Nothing is "perfect".
When you add in cameras that get their lens dirty and scratched, and radar systems that loose accuracy/range with outside conditions along with age and use, we end up with anti-collision systems that often do a good job. But, not always.

For example, I guess people never heard or rain, fog, dust, dirt, or snow?
It's true that some anti-collision, in some limited situations, have abilities that even the best and most alert driver can't match.
But again, we're talking some very specific very limited situations.


Btw, to be clear, I'm talking about anti-collision systems.
I'm not taking about "just" the ABS system (anti-lock brake systems).
Imho, ~98% of the ABS systems out there far far surpass any human ability, for many reasons.



Some Links:
http://jalopnik.com/new-crash-test-s...lis-1576767776

http://www.mercedescla.org/forum/5-c...st-tested.html

http://www.glaowners.com/forum/engin...e-testing.html


https://www.euroncap.com/en


Euro NCAP Testing Crash Avoidance Systems - on the Road with AEB


2014 Mercedes C-Class - Autonomous Emergency Braking test



Some people "trying to test a MB anti-collision with cardboard or some ?1/4"? wood paneling" and failing:
Collision Prevention Assist Plus - Posted by Robert Schneider


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Chuckman

Thanks for the info. I'm definitely not about to drive my vehicle into a wall, foam, cardboard, or real, as well as get too close to another vehicle to "test" the system. Maybe the system would stop my vehicle if I got too close to another vehicle. But in absence of any visual or auditory warnings, I still have my doubts. What is the driver assist image/graphic even for if it is just a static image and provides no information whatsoever?

Mr. Toad

I've kind of been wondering the same thing about my newly-acquired car. The VIN decode indicates that it has "258 COLLIS.WARN. SYS. W/ ACTIVE BRAKE INTERV. FCW STOP", and just like you, I've been tempted a few times to "test" the car to see if/how it responds. Also like you, I'll only push that so far, but I've not gotten any obvious response out of it to date.

Mr. Toad

Update: The system was unintentionally tested on my way to work this morning and it passed. I glanced down briefly when the car in front of me stopped short, and my car produced an audible alarm that got my attention. I stepped hard on the brake and stopped about a foot from the bumper in front of me. I'm not sure whether my car autonomously applied additional brake pressure or if it was all me.