How collision prevention assist works?
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Junior Member
Joined: Nov 2021
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CLS350D
How collision prevention assist works?
I have W222 2018 with CPA, I was few times in a situation where I could hit car in front of me.
On my W222 I get red triangle on screen and strong beeps, but car never applies breaking automatically.
Comparing it to my Volvo, Volvo automatically applies brakes automatically and stops the car immediately which makes me much more secure then Mercedes.
Should Mercedes also applies the brakes, do i need to activate it somewhere?
On my W222 I get red triangle on screen and strong beeps, but car never applies breaking automatically.
Comparing it to my Volvo, Volvo automatically applies brakes automatically and stops the car immediately which makes me much more secure then Mercedes.
Should Mercedes also applies the brakes, do i need to activate it somewhere?
Member
Joined: Nov 2009
Posts: 245
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'20 GLS450, '17 S550 Sedan
The answer depends somewhat on whether or not your W222 is equipped with the optional Driver Assistance Package. I've attached two videos below, the first of which describes the active braking functionality of the standard system, while the second video speaks to the additional functionality of the optional Driver Assistance Package.
In either case, the system will first give audible and visual warnings. If time passes and those warnings are not heeded with driver-initiated braking, the car will then initiate autonomous braking at the last possible moment to avoid the collision, while also tensioning the PRE-SAFE seat belts.
Frequently, in congested traffic situations, my vehicles will alert me of a rapidly slowing vehicle ahead with the audible/visible warnings that you describe, at which point I get on the brake pedal quickly to avoid a collision (i.e. the vehicle did not have to autonomously brake). Only twice in my life have I experienced autonomous braking, once in my previous W166 and once in my W222. In both cases, I was momentarily distracted while driving in congested city traffic at low speeds (20-30mph), but by the time I was alerted by the audible/visible warnings, the vehicle must've already determined that there wouldn't be enough reaction time for me to get to the brake pedal, so it did it for me.
The third video shows a "real life" demonstration and is fun to watch, if only to see the passion and excitement of the German Mercedes-Benz safety engineer proudly showing off his invention to this journalist (beginning at 0:16 in the video).
Hope this helps!
In either case, the system will first give audible and visual warnings. If time passes and those warnings are not heeded with driver-initiated braking, the car will then initiate autonomous braking at the last possible moment to avoid the collision, while also tensioning the PRE-SAFE seat belts.
Frequently, in congested traffic situations, my vehicles will alert me of a rapidly slowing vehicle ahead with the audible/visible warnings that you describe, at which point I get on the brake pedal quickly to avoid a collision (i.e. the vehicle did not have to autonomously brake). Only twice in my life have I experienced autonomous braking, once in my previous W166 and once in my W222. In both cases, I was momentarily distracted while driving in congested city traffic at low speeds (20-30mph), but by the time I was alerted by the audible/visible warnings, the vehicle must've already determined that there wouldn't be enough reaction time for me to get to the brake pedal, so it did it for me.
The third video shows a "real life" demonstration and is fun to watch, if only to see the passion and excitement of the German Mercedes-Benz safety engineer proudly showing off his invention to this journalist (beginning at 0:16 in the video).
Hope this helps!
Out Of Control!!
Joined: Nov 2018
Posts: 11,432
Likes: 5,343
From: San Francisco Bay Area
2019 C63CS
There's a balance to strike between these systems being overly intrusive and being a last resort if the driver doesn't react fast enough, and also to reduce false positives. There are plenty of reports out there where these systems intervened for no reason. The MB system is quite good, but keep in mind none of these systems guarantee that the car will come to a full stop before impact. The main goal is to reduce the severity of an impact. Best case scenario the car comes to a full stop before impact, but it's also acceptable if the speed is reduced to the point where the impact so no longer severe.
As mentioned above, the Driver Assistance Package makes a big difference in terms of what it detects and how. The package adds additional sensors such as a stereo camera instead of a mono camera as well as a forward facing radar sensor, so this makes it more capable.
In my own car I've had it apply the brakes quicker than I could when somebody ahead suddenly slammed on the brakes. It does work when it needs to. On the other hand it intervenes too soon on a race track when trying to brake late into a corner, so there it gets annoying, but thankfully it can be turned off at least in AMGs.
As mentioned above, the Driver Assistance Package makes a big difference in terms of what it detects and how. The package adds additional sensors such as a stereo camera instead of a mono camera as well as a forward facing radar sensor, so this makes it more capable.
In my own car I've had it apply the brakes quicker than I could when somebody ahead suddenly slammed on the brakes. It does work when it needs to. On the other hand it intervenes too soon on a race track when trying to brake late into a corner, so there it gets annoying, but thankfully it can be turned off at least in AMGs.
Senior Member
Joined: Jun 2007
Posts: 457
Likes: 253
From: SD
Various
The answer depends somewhat on whether or not your W222 is equipped with the optional Driver Assistance Package. I've attached two videos below, the first of which describes the active braking functionality of the standard system, while the second video speaks to the additional functionality of the optional Driver Assistance Package.
In either case, the system will first give audible and visual warnings. If time passes and those warnings are not heeded with driver-initiated braking, the car will then initiate autonomous braking at the last possible moment to avoid the collision, while also tensioning the PRE-SAFE seat belts.
Frequently, in congested traffic situations, my vehicles will alert me of a rapidly slowing vehicle ahead with the audible/visible warnings that you describe, at which point I get on the brake pedal quickly to avoid a collision (i.e. the vehicle did not have to autonomously brake). Only twice in my life have I experienced autonomous braking, once in my previous W166 and once in my W222. In both cases, I was momentarily distracted while driving in congested city traffic at low speeds (20-30mph), but by the time I was alerted by the audible/visible warnings, the vehicle must've already determined that there wouldn't be enough reaction time for me to get to the brake pedal, so it did it for me.
The third video shows a "real life" demonstration and is fun to watch, if only to see the passion and excitement of the German Mercedes-Benz safety engineer proudly showing off his invention to this journalist (beginning at 0:16 in the video).
https://www.youtube.com/watch?v=AQLOY-2GES4
https://www.youtube.com/watch?v=yW5xeFAIcRA
https://www.youtube.com/watch?v=zfq4xGXLIvM&t=212s
Hope this helps!
In either case, the system will first give audible and visual warnings. If time passes and those warnings are not heeded with driver-initiated braking, the car will then initiate autonomous braking at the last possible moment to avoid the collision, while also tensioning the PRE-SAFE seat belts.
Frequently, in congested traffic situations, my vehicles will alert me of a rapidly slowing vehicle ahead with the audible/visible warnings that you describe, at which point I get on the brake pedal quickly to avoid a collision (i.e. the vehicle did not have to autonomously brake). Only twice in my life have I experienced autonomous braking, once in my previous W166 and once in my W222. In both cases, I was momentarily distracted while driving in congested city traffic at low speeds (20-30mph), but by the time I was alerted by the audible/visible warnings, the vehicle must've already determined that there wouldn't be enough reaction time for me to get to the brake pedal, so it did it for me.
The third video shows a "real life" demonstration and is fun to watch, if only to see the passion and excitement of the German Mercedes-Benz safety engineer proudly showing off his invention to this journalist (beginning at 0:16 in the video).
https://www.youtube.com/watch?v=AQLOY-2GES4
https://www.youtube.com/watch?v=yW5xeFAIcRA
https://www.youtube.com/watch?v=zfq4xGXLIvM&t=212s
Hope this helps!
