I've had numerous false warnings, but no brake events. False warnings are infrequent enough that I decided to just liver with it.
Collision prevention assist plus
What has been the Forum's experience with this feature - active braking?
Has it worked for you? Have seen any false warnings/brake events?
Has it worked for you? Have seen any false warnings/brake events?
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What causes false events? Is there a pattern?
It works. Not more than an hour after we picked up our brand new GLA250 from the factory in Stuttgart we had some jackass (how do you say jackass in german?) dive right in front of us on the autobahn out of their stalled lane into our fast moving lane with no room to accelerate out of our way. I hit the brakes, the warning sounded, and the car hit the brakes harder than I was. The car did one of those full ABS kind of stops where you know it's hitting the very limit of not skidding. We wound up a few inches from the bumper of his beat up Golf. So yes, it works. Without it I hate to admit that I probably would have acted too late to avoid hitting him. How much would that suck to crash your new car after owning it for less than an hour?
I've had a few "false" alarms that I wouldn't really call false alarms, just overly cautious alarms. Like when a car is getting a little close but not directly in front of me, like just sticking into the road enough that you'd have to cross the line to avoid them, but I haven't had it beep for nothing. I haven't had the brakes kick in other than that first and very justifiable time.
I've had a few "false" alarms that I wouldn't really call false alarms, just overly cautious alarms. Like when a car is getting a little close but not directly in front of me, like just sticking into the road enough that you'd have to cross the line to avoid them, but I haven't had it beep for nothing. I haven't had the brakes kick in other than that first and very justifiable time.
I have gotten several false warnings (car beeps twice and the triangular icon flashes on the dashboard) on sharp curves. I guess the car thinks I am about to hit the firehouse I drive past often, but I am never close to doing so.
I don't think I've experienced it activating the brakes yet. Only have driven 1500 miles so far.
I don't think I've experienced it activating the brakes yet. Only have driven 1500 miles so far.
I get that on turns as well, left turn signal is on, waiting to disengage when I straighten out. It detects traffic turning with me in the left lane (double lane turn) and thinks I'm going to change lanes. I don't really mind that, since the blindspot assist feature is exceptionally a good one for lane changing with that notorious pillar blind spot.I have gotten several false warnings (car beeps twice and the triangular icon flashes on the dashboard) on sharp curves. I guess the car thinks I am about to hit the firehouse I drive past often, but I am never close to doing so.
I don't think I've experienced it activating the brakes yet. Only have driven 1500 miles so far.
No phantom brake warning yet...knock on wood!
I get warnings when cars in front of me turn off the road. I think the system suddenly sees cross traffic and reacts until it can tell the traffic is moving away.
I also get the occasional false alarm on curves that also have elevation changes.
I'm not bothered by it, rather it's good to know the system is working.
I also get the occasional false alarm on curves that also have elevation changes.
I'm not bothered by it, rather it's good to know the system is working.
You'd be surprised how often this actually results in a collision especially on busier streets. The car turning off the road has to suddenly stop because someone's crossing the street or there's something already there and the car behind them doesn't expect this, and bam! I don't mind the car reminding me of this.I get warnings when cars in front of me turn off the road.
It works - annoyingly a few days ago I was creeping behind someone - both of us moving, the guy ahead maybe 1mph slower, car slammed on the brakes. Very dangerous in my opinion since there was about 15 feet between us and we were going around 10mph in near bumper to bumper traffic.
Wonder how it will shake out legally if someone rear-ends me because of this.
Wonder how it will shake out legally if someone rear-ends me because of this.
I've had my car a couple of months now, and there have been frequent false warnings. In my case, the double- and sometimes triple-beeps really come out of the blue ... I am usually going straight, with no other vehicles or obstacles in the vicinity going either direction. The alarm seems to be quite random. I'm bothered by the unpredictability of it, and feel that it could cause a collision in the event that someone is behind me and the car slams on its breaks.
Generally the person behind you would be at fault. If you rear end someone because they brake suddenly (barring other factors like sudden lane changes) that means you were not paying attention or following too close.It works - annoyingly a few days ago I was creeping behind someone - both of us moving, the guy ahead maybe 1mph slower, car slammed on the brakes. Very dangerous in my opinion since there was about 15 feet between us and we were going around 10mph in near bumper to bumper traffic.
Wonder how it will shake out legally if someone rear-ends me because of this.
I got the opposite of the false alarm event. An error message in the instrument display, warning of the Collision Prevention Assist becoming inactive. The dealership crew seemed puzzled at first glance. They did the software upgrade, and the system got back on. My feeling is, that the false alarms may be coming from the same source, the software loopholes. The upgrades should take care on it.
The other day, the car in front of me decided to take the right turn lane and instead of taking the right turn he decided to jump into my lane. Before I could slamp on the brakes, the collision avoid thing kicked in with full braking and beep. I don't think I would have crashed so it seemed a bit weird. Nonetheless there goes the demo for me 
Id say overall it's 50-50. I really want an inflatable thingy to test it in a controlled way.
MB uses styrofoam blocks to train dealership auto demonstrators.Id say overall it's 50-50. I really want an inflatable thingy to test it in a controlled way.
I think of it like a bullet proof vest or airbags. Good to have it, hope you never need it, but do you really want to test it?I really want an inflatable thingy to test it in a controlled way.
My main concern was that when in snow it would ice over and malfunction but the other day when driving in snow it gave a collision assist unavailable message. I have gotten an occasional beep and brake when passing to close to another bumper but other than that nothing scary
One event where the brakes were applied -
I was gliding into a bear-right fork, close to the car ahead. Car ahead slams on brakes to stop for a skunk in the road. Yes, a skunk. GLA starts beeping and slams on brakes. It would have been a sure accident. His fault, but still.
I've had a bunch of false alarms but also a few times where I was looking at the scenery while cars ahead start to brake and the beeps give me enough time to get back to reality and apply the brakes myself.
I love the feature. A few false alarms are no big deal.
I was gliding into a bear-right fork, close to the car ahead. Car ahead slams on brakes to stop for a skunk in the road. Yes, a skunk. GLA starts beeping and slams on brakes. It would have been a sure accident. His fault, but still.
I've had a bunch of false alarms but also a few times where I was looking at the scenery while cars ahead start to brake and the beeps give me enough time to get back to reality and apply the brakes myself.
I love the feature. A few false alarms are no big deal.
has anyone tried the different sensitivity modes other than sensitive??
Not quite true on the fault - if you hit someone from behind then you will be at fault no matter why the person in front of you braked almost all the time (logic being you were following too close to be able to brake in time). Unless of course you mean the skunk's fault... Car Accidents: Proving Fault | Nolo.comOne event where the brakes were applied -
I was gliding into a bear-right fork, close to the car ahead. Car ahead slams on brakes to stop for a skunk in the road. Yes, a skunk. GLA starts beeping and slams on brakes. It would have been a sure accident. His fault, but still.
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