Automatic Emergency Breaking Front/Rear

Pitter

Pitter
Contributor
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2020 CX-5 Signature Azul Metalico
Has anyone had the chance to experience this? What conditions generate the effect? If the system stops you from crashing into the stopped car in front of how close are you when it activates? Also will it stop you from backing into a tree?
 
It varies wildly. DO NOT rely on it. Drive as if you don't have any of those systems, and hope that they'll work when you need them.
 
Yesterday I was driving on a 4 lane 55 mph road, all of a sudden the car in front of me slowed down as if it was going to stop.
The HUD starting screaming "BRAKE", I had already anticipated braking and was in the process. I don't know if the car was telling me it was braking or telling me to brake.
Anyway, I'm still unclear if it would of braked or not. I'm not taking the chance.

I don't think it will stop you in reverse.
 
What shadonoz said. All of these systems (like Cross Traffic Alert) are assists, not substitutes. But you know that. These are not Teslas ;)

I had it engage on me the first few days I had my car. There was a line of cars that were stopped for someone taking a left turn and I came up on them too quickly. BRAKE! flashed on my HUD, it beeped and the car braked. It happened so quickly I had to replay in my mind whether I had really come on that guy's bumper that rapidly. I think I had. I must have. I'm not sure why I had. I've never rear-ended another car. The only accident I've had that's been my fault was over 45 years ago. I was likely playing with the infotainment system and got distracted.

There are other times the BRAKE! has appeared/beeped. If you come up too quickly on someone who is in the process of turning out of your way and a portion of their vehicle is still in your lane of travel, you'll get it.

I've had it flash once when there was no reason for it to that I could see. It was early on a Sunday morning and there were no other cars around. It was either a critter I didn't see, something in the guy's yard in front of the car as I approached the sharp curve, or a glitch.

This system is driven by the front camera that's behind the rear view mirror. It does not work going in reverse.

My manual says the system senses cars and pedestrians at different speeds. It also says that the Advanced SCBS system operates in response to a vehicle ahead or a pedestrian. The system does not operate in response to obstructions such as a wall, 2-wheeled vehicles, or animals. (If I read correctly, only the Sport lacks the Advanced system...all other trims include it).
 
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I have the sport trim that has smart city brake support with only the camera. It has never gone on while driving nor when trying to get it to go on with half a dozen experiments. Even putting black tape over the camera doesn't make any error or warning light go on. I don't think it does anything on the sport trim. But I am not complaining, I am not a fan of autonomous braking.

Mine would perform like the BMW X1, from this video

https://www.youtube.com/watch?v=SEa0dce3xg4
 
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I have the sport trim that has smart city brake support with only the camera. It has never gone on while driving nor when trying to get it to go on with half a dozen experiments. Even putting black tape over the camera doesn't make any error or warning light go on. I don't think it does anything on the sport trim. But I am not complaining, I am not a fan of autonomous braking.

Mine would perform like the BMW X1, from this video

https://www.youtube.com/watch?v=SEa0dce3xg4

Mazda has been selling the full AEB package for 2019 as the i-activsense package for the sport trim for 625. The radar sensor replaces the front Mazda emblem and is used for higher speeds. Next year it will be standard along with a price increase.

Here's a relevant test of the AEB system.

 
I've never experienced AEB on the CX-5, but I had it on my Mazda6, and it would sometimes trigger if I tried to get the nose of the car into my garage while the door was going up, but before it had cleared the height of the roof. Most AEB systems only claim that they'll reduce the severity of an impact and not prevent one - the manufacturers are leaving themselves an out if the system doesn't stop in time.
 
Has anyone had the chance to experience this? What conditions generate the effect? If the system stops you from crashing into the stopped car in front of how close are you when it activates? Also will it stop you from backing into a tree?

3-4 weeks after I got my '19 signature, this feature of our car saved my ass, and likely prevented the car from being written off.

I had a video of it, but can't find it.

Essentailly, someone made a blind-left turn in front of me just as someone in the lane beside me to the left decided to [illegally] veer into my lane. (I was in the right lane, traffic in the left had stopped to allow someone to turn). I had already seen that traffic had slowed so I was slowing down when the car veered in front of me. That car then had to slam on his brakes to prevent hitting the car making the blind left turn in front of us.

SInce I was already braking, I began to brake harder however, the auto-braking system must have recognized I was not applying enough pressure. the "BRAKE!" visual popped up on my HUD display, with the audible warning, and the vehicle came to an abrupt stop, about a foot from the guy in front of me.

It saved me. Big time.

TO be objective, I will also tell you that it will give you false-positives sometimes. For example, if someone is turning right into a parking lot and making a career out of it, and the system senses you aren't slowing down enough, it will "BRAKE!" you (visual and audible alarm) but will not put the brakes on unless it senses you're going to hit the car.

Some others have reported that in situations like this the car has slammed on the brakes, but 12,000km in, I have NOT had this experience.

All in all, I'm very glad I have the system in the vehicle. It proved itself to me.
 
3-4 weeks after I got my '19 signature, this feature of our car saved my ass, and likely prevented the car from being written off.

I had a video of it, but can't find it.

Essentailly, someone made a blind-left turn in front of me just as someone in the lane beside me to the left decided to [illegally] veer into my lane. (I was in the right lane, traffic in the left had stopped to allow someone to turn). I had already seen that traffic had slowed so I was slowing down when the car veered in front of me. That car then had to slam on his brakes to prevent hitting the car making the blind left turn in front of us.

Since I was already braking, I began to brake harder however, the auto-braking system must have recognized I was not applying enough pressure. the "BRAKE!" visual popped up on my HUD display, with the audible warning, and the vehicle came to an abrupt stop, about a foot from the guy in front of me.

It saved me. Big time.

To be objective, I will also tell you that it will give you false-positives sometimes. For example, if someone is turning right into a parking lot and making a career out of it, and the system senses you aren't slowing down enough, it will "BRAKE!" you (visual and audible alarm) but will not put the brakes on unless it senses you're going to hit the car.

Some others have reported that in situations like this the car has slammed on the brakes, but 12,000km in, I have NOT had this experience.

All in all, I'm very glad I have the system in the vehicle. It proved itself to me.

Echoing this sentiment. I had the EXACT same thing happen to me during my first year of ownership with my CX-9 (someone cut in front of me then braked hard to avoid an accident).

I've had the same experience with a couple of "false-positives", thought I'll admit that in my cases the system was doing what it was designed to do, and I was just being too impatient.
 
Like others have said, if someone is making a turn from your lane and it doesn't think you're going slow enough it will trigger a BRAKE! message. Unfortunately I've had a few instances of people suddenly moving into my lane that would have resulted in an accident if I hadn't slammed on the brakes, but the safety systems did not trigger at all.
 
Yesterday I was driving on a 4 lane 55 mph road, all of a sudden the car in front of me slowed down as if it was going to stop.
The HUD starting screaming "BRAKE", I had already anticipated braking and was in the process. I don't know if the car was telling me it was braking or telling me to brake.
Anyway, I'm still unclear if it would of braked or not. I'm not taking the chance.

I don't think it will stop you in reverse.

I've had the HUD flash brake a few times while I was not braking
 
Like others have said, if someone is making a turn from your lane and it doesn't think you're going slow enough it will trigger a BRAKE! message. Unfortunately I've had a few instances of people suddenly moving into my lane that would have resulted in an accident if I hadn't slammed on the brakes, but the safety systems did not trigger at all.

Ideally it should only brake hard on its own at the last possible moment. Its much quicker to react than a person, so that last possible moment is later than when you were able to successfully brake. It was probably poised to brake a little harder than you did about 200 milliseconds later, had you not. In that type of split-second consideration, there's no point in trying to prod you to brake with a message because there isn't time to assimilate and respond to the message.

Like many, I've had the BRAKE! message a few times with a dawdly right-turner in front of me. I'd prefer it not do that, but I accept it, the parameters have to be set somewhere, and in a case like that where there is plenty of time, it should give some warning if it's poised to brake for you if necessary. Fortunately I've never had it actually brake when I'm going around somebody or timing their departure from my path. That would be pretty disconcerting, if not downright dangerous. I don't know if the Mazda makes any consideration for whether another car is barreling down from behind.
 
My sales person said something about the car breaking if rear ended so as not to plow into the car in front. I'm not real clear on that though.
 
Yesterday I was driving on a 4 lane 55 mph road, all of a sudden the car in front of me slowed down as if it was going to stop.
The HUD starting screaming "BRAKE", I had already anticipated braking and was in the process. I don't know if the car was telling me it was braking or telling me to brake.
Anyway, I'm still unclear if it would of braked or not. I'm not taking the chance.

I don't think it will stop you in reverse.

Not sure if you had the chance to read my post, but the BRAKE! warning is letting you know that it's anticipating that you are travelling too fast compared to the car in front of you. It's likely seeing that they are slowing rapidly (to turn, for example) and its' warning you.

The car *would* have taken over had either a) the car not moved out of the way / sped up or B) You did not brake hard enough to stop.

The audible and visual warning are advising you of an impending collision - its warning you to take actions and if you don't, it will.

I will say this - there is one major downside to this. You might avoid a front end collision, but in my instance where it took over and braked for me (because the turd in front of me cut me off and slammed on his brakes), I had NO control over the braking and the car came to an ABRUPT stop. Had there been someone behind me not paying attention, they would have hit me.

However, I'd rather have to deal with a rear-end collision (in most cases unless its a truck or at highway speeds) than a front end one *I* caused.
 
My sales person said something about the car breaking if rear ended so as not to plow into the car in front. I'm not real clear on that though.

The logic sits with me on this - because I doubt the car is smart enough to know its been hit from behind.

So, it's still thinking you're being a dumb-ass and not paying attention lol.

That makes sense to me.

In fact, on my 2004 Mazda 6, I had this exact scenario happen to me. I got hit from behind at a very low speed, but he bumped me hard enough that I rolled into the car in front of me.
 
I would like more information on the auto hold system.

There is this: https://owners-manual.mazda.com/gen/en/cx-5/cx-5_8ft1ee17b/contents/05050700.html

But I am curious if the system would hold the vehicle as securely with auto hold versus you holding the brake pedal.
I am guessing the electronic parking brake actuator is what holds the vehicle in auto hold mode, so it might react differently to a rear impact. It wouldn't hold the vehicle as securely in a crash, but that could be a good thing or a bad thing.
 
I just read that if the AutoHold brakes are on for a period of time, the Electronic Parking Brake is engaged. So by that verbiage, it makes no sense that the mechanism is the same, if that's what you're implying.

I can't figure out how to engage the system. Do you have to turn it on before you start driving? I've tried to engage it while in D at a traffic light and it would not turn on...not that this is an important function for my driving conditions. If I were still in DC traffic I would have figured it out by now.
 
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