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Discussion Starter #1
Apparently, this is fitted as standard but I can't find it on my spec sheet however I can find the option for it in the menus on the MBUX??

Not quite sure if I do actually have it and what it is supposed to do....

When I've been driving on the motorway I've had the red triangle come up (collision warning) warning me that I'm too close to the car in front but I've never felt it braking for me. I've tried to push it to see if it does do any sort of braking and doesn't seem to and there's only so far you can risk it/try it :confused::confused::confused::confused::confused::confused::confused:

I have the A180D with Premium Plus Package
 

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Applicable to the 176 model, Brake assist only works when YOU apply the brake. It will apply the correct brake pressure to bring the car to a halt prior to contact (you hope!!).
It is not an automatic braking system. The nearest you’ll get to that is the braking on Distronic Plus cruise control.
I would suggest it would be extremely difficult (dodgy) to test your Brake Assist system
 

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Active brake definitely works for me, and it’s HAS braked on my behalf before (and not just apply more breaking force). This happened on a 30 mile/hour road, car in front of me was slowing down to turn off. My car decided I wasn’t slowing down fast enough and slammed the brakes on. Quite a scary experience because it doesn’t brake softly.
 

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On the W177 it applies assistance if your are already braking but not hard enough (it thinks) and it will brake if you are doing nothing at all. It happened to me once, where a pedestrian darted out in front of me. I saw him and had no worries - I was only doing around 15mph - but the car thought different and braked to a standstill based purely on the proximity and the fact that I was not braking at all at that stage.



This is one autonomous feature that I like; unlike the active lane assist where you haven't really a clue what it's going to do in an emergency situation.
 

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Discussion Starter #8
It is the W177 model I have.

Just find it odd that it’s not on the spec sheet etc for the car and I’ve never noticed it working I’m wondering is it a later feature that was added. I got mine end of June so in the first release.
 

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It is the W177 model I have.

Just find it odd that it’s not on the spec sheet etc for the car and I’ve never noticed it working I’m wondering is it a later feature that was added. I got mine end of June so in the first release.
Mine is from June, and it has it (AMG premium). It may not be on the spec sheet because I believe it’s standard on all models.
 

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It is standard across all models. And adzzie, you wouldn't notice it in everyday driving unless you got too close to an object. That means it's working as intended. The red triangle and alarm is a precursor to the automatic braking. If you take your own action to limit the closing in, nothing more will happen and the light will extinguish.
 

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There are 3 alert levels (I think).
- Red Triangle - Just alert
- Red Triangle and an audible alarm
- Automatic braking.

I already happened to use the 3rd level of alert, and I got the feeling that the car activated the braking, without my intervention, by instinct we go with the foot to the brake.
 

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I get these levels on the motorway:
- red triangle: car in front, watch out
- blinking red triangle: you’re getting very close now, increase distance
- warning beep - I am about to brake
- braking (I have never had this happen on the motorway)
 

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On the W177 it applies assistance if your are already braking but not hard enough (it thinks) and it will brake if you are doing nothing at all. It happened to me once, where a pedestrian darted out in front of me. I saw him and had no worries - I was only doing around 15mph - but the car thought different and braked to a standstill based purely on the proximity and the fact that I was not braking at all at that stage.



This is one autonomous feature that I like; unlike the active lane assist where you haven't really a clue what it's going to do in an emergency situation.
I had exactly that happen to me tonight, for the very first time! And yes, it’s very disconcerting! I had seen the pedestrian who darted across in front of me, and was breaking enough to avoid him, but my car decided the correct course of action was petty close to what you’d class as an emergency stop, brakes came on HARD!
 

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I had it go off when a bird flew in front of the car. That is when it becomes a shock when you are not even expecting to stop.
 

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The feature, whilst a good idea, has been implemented badly. Anything where the car overrides your actions without indication is dangerous. I have had times where the brakes have applied without any justifiable reason. Applying the brakes when the only thing in front of the car is a a grassy bank and that some 20m away.

If you are applying the brakes, either to lightly to check speed or more heavily with the aim of stopping, the car should not re-double the braking effort.

I have experienced the unwarranted application of brakes on a number of occasions that actually puts myself and the car at risk. I have been fortunate in that on each occasion when this has happened the roads have been dry with firm grip and nobody has been too close behind me. If this action happens when the roads are wet or icy this could lead to a very different outcome.

I know that the feature can be disabled, but this must be done each time you make a journey, very inconvenient. I had my car in for diagnosis a few weeks ago, but they found nothing of course. At this time they applied a software upgrade after which the ability to switch off became available (I'm sure it wasn't on the car before, I'd looked for it). If you have no confidence in the operation of a feature and have to disable it everyone you drive, then it is dangerous.

I'm at the point where I'm seriously considering returning my car on the basis that it is dangerous and unfair for purpose.
 

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The feature, whilst a good idea, has been implemented badly. Anything where the car overrides your actions without indication is dangerous. I have had times where the brakes have applied without any justifiable reason. Applying the brakes when the only thing in front of the car is a a grassy bank and that some 20m away.

If you are applying the brakes, either to lightly to check speed or more heavily with the aim of stopping, the car should not re-double the braking effort.

I have experienced the unwarranted application of brakes on a number of occasions that actually puts myself and the car at risk. I have been fortunate in that on each occasion when this has happened the roads have been dry with firm grip and nobody has been too close behind me. If this action happens when the roads are wet or icy this could lead to a very different outcome.

I know that the feature can be disabled, but this must be done each time you make a journey, very inconvenient. I had my car in for diagnosis a few weeks ago, but they found nothing of course. At this time they applied a software upgrade after which the ability to switch off became available (I'm sure it wasn't on the car before, I'd looked for it). If you have no confidence in the operation of a feature and have to disable it everyone you drive, then it is dangerous.

I'm at the point where I'm seriously considering returning my car on the basis that it is dangerous and unfair for purpose.
Have you gone down this route? My car keeps performing Emergency brakes for absolutely no reason (nothing on the road in front)? I have reported this to Mercedes 8 times now and they have just done software updates.
 

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I sold my then new Subaru outback because it was so bad with regards to emergency braking. It was simply way too overreative and would slam on the brakes at many inappropriate times. Like big D mentioned, especially when a car is turning in front, normally I would predict the speed and coast past after the car has turned but the Subaru use to go nuts and slam on the brakes and scare the s:*t out of me. The merc is actually not that bad in comparison. I have been caught out a few times but nowhere near as bad as the subi was, so I have accepted to have it happen every now and then if it might save me in a future situation. Don't get me started about active lane assist though... It s%*ts me to tears.
 
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