2021 Yaris emergency braking issue

[Ralph H]

25 minutes ago, Cyker said:

 I have now learned, that feedback pressure is totally false/artificial and has no bearing on how much braking you are doing, and I closed on the car in front much faster than I should have been from the feedback I was getting from the pedal!

 

I’ve noticed the same thing, pedal feel is inconsistent particularly when slowing gradually, as it transitions from regen to real braking it feels like the brakes slightly release and you have to press harder to stop. My old mk3 hybrid never did this but it’s brakes were more grabby than the mk4. 
The story’s here about auto braking have me slightly worried I’ve had a few brake alarms but so far it’s not actually taken over and stopped itself. 

[Cyker]

To be fair, it's generally not a problem unless you're driving in a highly congested city with lots of impatient aggressive drivers and narrow roads.

The system is set up perfectly for what I would loosely define as 'normal' road conditions. 99% of all my false positives have been in London, which is the poster-child for impatient aggressive drivers and narrow highly congested roads (Which the local councils are doing everything they can to make even worse! Yay!)

It's just unfortunate that most of my driving is for work in London  

 

[Mojo1010]

Looks like when I eventually get the MK4 I will have to turn off most of these settings as driving in London. Turn it on when it's being driven out of the city. 

[Cyker]

You just get used to it TBH - I can almost predict when it's going to beep at me and it's rare that the auto-brake actually triggers, as opposed to just warning, although it's a bit of a shock when it actually does!

The irony is you're far more likely to crash in London so I find it hard to turn it off - Two of the times the system has saved me; Once when someone just pulled out of a side-road to turn right without looking properly, and then upon seeing me at the last moment, just stopped fully across the road like a total plonker in the perfect position for me to ram the driver-side door into them (If they'd just continued it would have been fine! Uncomfortably close, but fine!)

The car reacted far quicker than I did and stopped so quickly that there was probably enough space for them to fully open their door (I was too busy swearing and honking at them out of shock and also probably some light bruising of the ribs from the seatbelt locking up - The brakes in the Mk4 are *really* good!!  Morse-so as they fixed the ABS compared to earlier models!!)

Another was someone who either doesn't understand how mini roundabouts work or was very overly optimistic about the performance of their car and, again, just cut in front of me suddenly as I was coming round; This sort of thing is very common and I was half-anticipating it so it was a toss up between whether it was me or the car that got the brakes down first, but it was close!

Because this sort of terrible driving is so normal in London (To the point where I've seen this sort of thing happen with a police car in view and they didn't bat an eyelid), I'm too paranoid to disable the system completely!

TBH I'd just avoid London if you can help it; Between KHAAAAN! and the local councils anti-car policies the roads have become more congested, more polluted and more dangerous and that doesn't seem like it's going to change anytime soon...

 

[anchorman]

The brake pedal feel is replicated on a Yaris.  Unlike other cars it has to have brake assistance when the engine is switched off because you can drive quite a long way on Battery power.  It simulates the effort needed based on pedal stroke and then uses accumulated pressure to deliver accordingly.  It might be a bit off the mark but I’ve driven conventional systems that feel either dead or over boosted to the point it’s hard to control.  

[Cyker]

Yea, AFAIK*, it uses a hydraulic pump to supply brake pressure - the master cylinder doesn't do anything other than supply pressure to a sensor, unless the system fails and goes into its failsafe mode.

I think it still operates with a conventional brake booster, with the vacuum supplied by another electric pump (As you say, the engine isn't always running so can't tap it for vacuum!).

I'm not sure what system it uses to supply pedal feedback - The blurb suggests it simulates pedal force based on braking pressure, but in my experience this isn't the case at all and it just feels like I'm pushing against a spring or something.

 

Edit:

* As Far As I Know  

 

[anchorman]

21 hours ago, Cyker said:

Yea, AFAIK*, it uses a hydraulic pump to supply brake pressure - the master cylinder doesn't do anything other than supply pressure to a sensor, unless the system fails and goes into its failsafe mode.

I think it still operates with a conventional brake booster, with the vacuum supplied by another electric pump (As you say, the engine isn't always running so can't tap it for vacuum!).

I'm not sure what system it uses to supply pedal feedback - The blurb suggests it simulates pedal force based on braking pressure, but in my experience this isn't the case at all and it just feels like I'm pushing against a spring or something.

 

Edit:

* As Far As I Know  

 

It has an electric motor booster, not vacuum.........

 

[Derek.w]

With regards to brake alarm on the odd accasion it shown on the dash it cancels as I  drives the car around a obstical.

(parked car at side of road or approaching rounderbout or junction).

[MissC]

My brand new Corolla did an emergency stop for no reason recently and I am too nervous to drive it. Horrified to see that it happened to someone else at 60mph. I took it back to the dealer who says its all working normally and they turned the sensitivity down. However now it seems to be breaking even in normal traffic - not emergency stop level, but definitely assisting with breaking. I wish I had never bought it and I am interested if anyone has succeeded in getting it fixed or their money back by Toyota. 

 

[anchorman]

1 hour ago, MissC said:

My brand new Corolla did an emergency stop for no reason recently and I am too nervous to drive it. Horrified to see that it happened to someone else at 60mph. I took it back to the dealer who says its all working normally and they turned the sensitivity down. However now it seems to be breaking even in normal traffic - not emergency stop level, but definitely assisting with breaking. I wish I had never bought it and I am interested if anyone has succeeded in getting it fixed or their money back by Toyota. 

 

They don’t brake for no reason, it’s impossible.  It’s seen something it considers a risk but you don’t and it doesn’t assist in braking.  The feel of the brakes is different than other cars because it’s using braking to regenerate the Battery.   It’s just a feel of the car that you’ll get used to and you might need to adjust your driving style.   I once had a similar conversation with a taxi driver but after riding with him for a period of time, I was not at all surprised the car was nervous.  If you really can’t live with it you might have to lose a lot of money by trading it.  

[Cyker]

You have to drive it like you have a nervous passenger; If you're like my other London bretheren, you're probably used to driving too close to the car in front.

I've had to force myself to leave a bigger gap so if the car in front of me stops suddenly it doesn't trigger the AEB, as well as not slalom through traffic islands and parked cars at the kind of speeds I used to for the past 20+ years of driving.

Just move off slightly slower than the car in front to allow a gap to build and try to get out of the habit of hanging right on their rear bumper in lock-step; It'll take some getting used to but it stops freaking out the AEB and also does wonders for the mpg!

[Ralph H]

Today my Yaris emergency braked for the first time since I got it 2 years ago. The only reason I can think why is that there was a cyclist waiting to join the road from the left, he was waiting behind the white light for traffic to pass. When I got parallel to him the brake alarm sounded and immediately braked for “no reason.” The car behind also had to slam on to avoid ramming me needless to say he wasn’t happy. I’m convinced these safety systems are not fit for purpose. 

[anchorman]

4 hours ago, Ralph H said:

Today my Yaris emergency braked for the first time since I got it 2 years ago. The only reason I can think why is that there was a cyclist waiting to join the road from the left, he was waiting behind the white light for traffic to pass. When I got parallel to him the brake alarm sounded and immediately braked for “no reason.” The car behind also had to slam on to avoid ramming me needless to say he wasn’t happy. I’m convinced these safety systems are not fit for purpose. 

You can fool it depending on the angle but look at it the other way.  If you were distracted and he was at risk it might have saved him to generate even more CO2 and particulates for the atmosphere.  

[ashmj]

We have this nonscense on a 2024 Yaris Cross, it brakes by itself. In the UK, part of my driving test was you are meant to be in control of the veichle at ALL times but with this thing you are not. I hate this car with a passion.

Ours can be turned off in the menus but next time you switch on it is reactivated, have I mentioned that I hate this car.

I think on this thing it is classed as "Collision Detection" which is Euro legislation as of July 2024

Hardly a safety factor, I said much the same "what if it decides to do an emergency stop".

Time to get the 1983 Ford Escort back on the road and decide myself when to do an emergency stop.

 

[MikeSh]

39 minutes ago, ashmj said:

I hate this car with a passion.

 

39 minutes ago, ashmj said:

I think on this thing it is classed as "Collision Detection" which is Euro legislation as of July 2024

So if you want a shiny new toy you're a bit stuck. 

[MikeSh]

6 hours ago, Ralph H said:

When I got parallel to him the brake alarm sounded and immediately braked for “no reason

If by "parallel" you mean next to him then he wasn't the problem. More likely it was something further ahead, like a parked car that was seen by the car as a threat but you were concentrating on the cyclist and hasn't noticed it. It happens.

[TonyHSD]

1 hour ago, ashmj said:

We have this nonscense on a 2024 Yaris Cross, it brakes by itself. In the UK, part of my driving test was you are meant to be in control of the veichle at ALL times but with this thing you are not. I hate this car with a passion.

Ours can be turned off in the menus but next time you switch on it is reactivated, have I mentioned that I hate this car.

I think on this thing it is classed as "Collision Detection" which is Euro legislation as of July 2024

Hardly a safety factor, I said much the same "what if it decides to do an emergency stop".

Time to get the 1983 Ford Escort back on the road and decide myself when to do an emergency stop.

 

Not a bad idea for the old escort. 
Will definitely bring back the smile on your face , plus it’s a classic one now so tax and all emissions restrictions free 👌👍 

[Cyker]

On 6/26/2024 at 6:00 PM, Ralph H said:

Today my Yaris emergency braked for the first time since I got it 2 years ago. The only reason I can think why is that there was a cyclist waiting to join the road from the left, he was waiting behind the white light for traffic to pass. When I got parallel to him the brake alarm sounded and immediately braked for “no reason.” The car behind also had to slam on to avoid ramming me needless to say he wasn’t happy. I’m convinced these safety systems are not fit for purpose. 

I've had that, although it only triggered it for a second and didn't actually stop the car - The system seems to be very sensitive to cyclists (and pedestrians!) and if it sees one and they even twitch forward slightly it can sometimes trigger the AEB; Especially when the cyclist has their wheel over the edge of the road, which most of them do when waiting.

All you can do is move away a bit or try to angle the car so it's heading slightly away from them and reduce speed to reduce the chances of it triggering.

It's definitely an unpleasant sensation when it triggers but I fear I'm becoming inured to it because it's happened to me so much... As I've said before, the system really isn't set up for the tight road situations of urban environments like London...

The worst thing is it's so inconsistent - I've had people just run across the road in front of me and it didn't bat an eyelid, while others have waited past the edge of road, and the system had braked the opposite wheels for a second as I passed them.

[Cyker]

On 6/27/2024 at 12:06 AM, MikeSh said:

If by "parallel" you mean next to him then he wasn't the problem. More likely it was something further ahead, like a parked car that was seen by the car as a threat but you were concentrating on the cyclist and hasn't noticed it. It happens.

It still might be - Mine is very sensitive to cyclists and pedestrians at close range; Once few times I've been in a specific situation where a cyclist is waiting at the lights doing that back-forth movement they always seem to do, and when it went green for us I started to move off only for the AEB to trigger momentarily as I got right next to them (i.e. 'parallel' to them), which I suspect is due to that back-forth motion and the fact that their wheels is overhanging the pavement and I'm very close to them. Luckily these have all been at very low speeds as I'd moved maybe a metre, but there are definitely a lot of edge-cases the system doesn't react to appropriately or safely.

I still think these systems are a terrible idea - As I always say, we should be improving driver standards instead of trying to improve safety using unproven tech as a crutch, esp. as it will never work fully as intended in the real world.

All this stuff is doing is encouraging drivers to be inattentive - Why bother doing your checks when the car will do it for you? You can just chat with your mates, don't bother checking the mirrors when reversing since the car will stop for you, do your make up with both hands while eating your burger etc.

 

[dannyboy413]

9 minutes ago, Cyker said:

do your make up with both hands while eating your burger etc.

 

I'm much too sensible and careful for that - I only use one hand to put my make up on. 😊

[MikeSh]

3 hours ago, dannyboy413 said:

I'm much too sensible and careful for that - I only use one hand to put my make up on. 😊

I suspect that anyone who uses make-up is more interested in themselves than any aspect of safety or good driving. 

Drop dead gorgeous is more than a catchy saying 😁

[ElaineMC]

I have a fairly narrow drive, but have been reversing into it for the last 34 years with no problems in my previous cars, but my 2024 Yaris Cross does an emergency stop between once and four times each time I get home while backing the car to where I usually park it on the drive.  It's especially infuriating since there seems to be absolutely nothing in the way. Maybe a blade of grass, but nothing substantial, and I've already removed all the nearby grass from both edges.

[dash]

@ElaineMC I had the same problem and cured it by disabling PKSB (parking support brake system) in settings. Once done you’ll see a constant orange warning light in the instrument display (because not all systems are now enabled), and each time you start the car you’ll have to clear the pop-up alert by pressing the ‘back’ button on the steering wheel, but a small price to pay to cure the emergency braking when reversing in your driveway 😉

[ElaineMC]

2 hours ago, dash said:

@ElaineMC I had the same problem and cured it by disabling PKSB (parking support brake system) in settings. Once done you’ll see a constant orange warning light in the instrument display (because not all systems are now enabled), and each time you start the car you’ll have to clear the pop-up alert by pressing the ‘back’ button on the steering wheel, but a small price to pay to cure the emergency braking when reversing in your driveway 😉

Thank you, I'll try that.

[Cyker]

Yeah it tends to freak out if the proximity sensors are close enough to sense the walls either side, and you're moving even slightly towards one of them.

You either have to do it veeeeery slowly or disable the PKSB as mentioned above.

I'd love to see the self-parking system attempt it