Sudden brake operation with rapid beeping.

[Louie]

Now having spent some time trying to master the CHR PHEV controls etc I wrongly assumed I had a 100% mastery of it all.

Every now and then the CHR  brakes suddenly accompanied by three quick beeping noises which I assume is collision avoidance. However non of this makes sense because I have yet to be in such a scenario. This normally happens under 30mph and with parked vehicles present on both sides of the road in particular large vans or largish 4x4's pickups. My impression is that the CHR's crash prevention system wrongly assumes that I am about to hit one of these largish vehicles despite the fact I am a good distance away and positioned on a clear pathway. This appears to be a random event and its beginning to drive me crazy. Has anyone any idea how I can moderate this ?

[SJFH]

Hi Louie,

I have had something like this - Warning light, bleep but no breaks though, all whilst driving safely in narrow streets with parked cars.

A short time after that, I was stopped at traffic lights and all the lights and bleepers went off when pedestrian cut in front of me crossing the road - scared the 💩 out of me.

Made me wonder though whether large bugs or debris were flying in front of the car to spring the alarms. 

You can set the sensitivity of the radar through the options menu (couldn't find the page in the manual) but I'm not sure if it is for parking only and not crash protection.

[Louie]

Hi Simon recently I had a very  alarming incident where my CHR PHEV suddenly decided to brake sharply for no particular reason  this time without the warning beeps. The road in particular had parked vehicle on both sides is quite wide, straight  and is a 40mph limit which I was well within. I find this quite a worrying trend in that if I was being followed to closely by another vehicle this could have been a rear end shunt.

This is the fifth time  this has happened and what is odd is it has taken place always  in the same  road but not in the same section and  at not a particular busy time   with sign of any moving traffic at all. Also it does not exhibit these characteristics while driving elsewhere.

I think this could be a sensitivity issue with the way my CHR detects parked vehicles ahead and after having spoken to my dealer its going in for them to see if they can make some adjustments to these possible sensitivity issues. 

 

[Alan3]

I've had the warning beeps and a large, red "Brake!" warning, but not the automatic braking, several times with my new Corolla.

There are two situations that seem to cause it: first, if there's a car parked on a bend in the road then as I approach the bend but haven't started to turn the wheel the collision avoidance will have conniptions because I appear to be heading straight for the parked car; it shuts up as soon as I turn the wheel. Second, if there are cars parked a fair distance apart, I pull out to go round one and then momentarily get back into my lane as I approach the next, I'll get beeped at since I'm temporarily on a collision course with the parked car.

The beeps when a pedestrian walks in front of you while stopped at the lights are the parking sensors detecting something very close to the front of the car. Scared the living daylights out of me the first time it happened.

The only time the Corolla has automatically braked on me was when I was trying to reverse into a parking space at the local RHS garden: there was some tall grass about 2 feet out from the back of the space and I was going to hit it... the car literally would not go into that space.

[Tim Bird]

Has occurred with my Corolla Touring Sports yesterday when I was activating Parallel Park Assist; it suddenly thought I was too close to the furthest car I was parking between and slammed the brakes on. I was not that close to the car. My passenger was similarly confused.

[Louie]

Hi Guys let me make myself clear. The sudden braking with or without beeps has occurred while driving down a wide straight wide  road at a constant speed with no movement of traffic in a 40 mpg zone with cars/vans parked on both sides and stationary. I have also had similar instances in the same road  road with parked and slow moving traffic in both direction. The braking in this instance appears to be short lived and less violent. 

The really bizarre thing this does not happen all the time whenever I use that road and is totally random. My Adaptive cruise control, collision prevention  etc are switched off at that time.

 

[SJFH]

Hi Louie,

It sounds as if you have an intermittent problem.

A friend of mine had this with his new Renault where it would slam the brakes on on the motorway for no reason. He took it back to the garage several times under warranty. Each time they came back and said they hadn't found any faults. On the third time they replaced the radar sensor under pressure from my mate, but still the problem re-ocurred. After the final visit to the garage where they said they found nothing and hadn't done anything they hadn't tried already - the problem disappeared!!

As you have a new car, get the dealer to check it out and don't give up until the problem is sorted!

 

[forkingabout]

If you have a dash cam pull the footage from the incident / incidents so you can show the service desk person what's happening.

 

[Louie]

Forking about excellent idea thanks.

[Haliotis]

I frequently get the beeps, and my MFD goes red with a warning to brake.  This mostly happens on a main road where I approach the road where we live.  This main road bends slowly to the right, and there are usually parked cars on the bend and are on my left.  If an oncoming car approaches and I stay to the left until the last moment, my trajectory briefly points me towards these parked cars, and my forward camera assumes that a collision is imminent.

I have also had my vehicle beep and brake hard when a car or pedestrian has passed close to the rear of my car as I reverse out of a parking space- usually on a supermarket car park.  As I have become familiar with the car, I know roughly what to expect, and when to expect it, so do not now reach panic-button reactions.

[Cyker]

I've got a load of clips where my Yaris flashes up BRAKE! for no apparent reason.

I've learned to drive it slower and leave bigger gaps, as the system really isn't set up for tight urban roads.

In your case, I'd take it back to the dealer and make them aware of the problem. Dashcam footage would be helpful. It might be worth getting them to recalibrate the ADAS to see if that helps.

However, in my case they just said the system is working as intended and they can't do anything about it.

[Louie]

Today my CHR PHEV performed the same routine in the same 40 mph road and had slowed down to 18mp and would have stopped if I had not pressed the go pedal.

There was no discernible traffic movement close by and my ACC was switched on but I had not been following any traffic and the culprit appears to be a Honda Civic minding its own business parked by close to the kerb by the side of the road. 

Pleases see attached AVI file for a record of the incidence where the CHR starts to apply the brakes  while I am legally following the observed speed limit of 40 mph. . My CHR has done this in more or the same exact  location but more violently accompanied  by 4 to 3 sudden beeps for no apparent reason.

I spoke to the dealer today who want to see the AVI file and mentioned that dirt or muck on the sensor located in the front Badge can cause a "radar" malfunction. I am sceptical about that simply because my problems only seem to be more prevalent in one location and rarely happen elsewhere.

[Louie]

A brief addition,  my CHR front "radar" does not like largish bus shelters or flagpoles with limp Union Jacks clinging to them. Whenever my ACC was on the car braked from 30/40 mph while passing these objects and the CHR PHEV does it every time. See pics (vids are too long so captured images only) 

My dealer has stated that he thinks that the flag is definitely the culprit but is undecided on the bus shelter. The dealership want to borrow my CHR and give me a loaner currently I am a bit nervous handing  over Clarisse" despite  here irritating habits.

[AndyRC]

14 hours ago, Louie said:

A brief addition,  my CHR front "radar" does not like largish bus shelters or flagpoles with limp Union Jacks clinging to them. Whenever my ACC was on the car braked from 30/40 mph while passing these objects and the CHR PHEV does it every time. See pics (vids are too long so captured images only) 

My dealer has stated that he thinks that the flag is definitely the culprit but is undecided on the bus shelter. The dealership want to borrow my CHR and give me a loaner currently I am a bit nervous handing  over Clarisse" despite  here irritating habits.

The ACC does not react particularly well to parked vehicles on the near side even if you have positioned the car in the road to avoid them by a decent distance. I regularly use the ACC in 30/40 mph zones to but often pause it when there are parked vehicles.  I should say it works perfectly on motorway / dual carriageway and when in long queues of traffic. 

[Primus1]

However, we had an incident last year where my wife was driving, as she accelerated up the slip road joining a dual carriageway, a learner suddenly decided to stop suddenly, the safety system activated preventing a rear end smash, ( I do believe this was an attempted crash for cash scam)

 

 

[CassUK]

Twice in the past week my car has  slowed down significantly in traffic on the A1 (single carriageway sections) when the car in front was turning off left at either a junction or lay-by - I had ACC activated on both occasions and had to intervene by switching it off to prevent coming to a stop or slowing down to a speed where the traffic behind was affected. It seems it  thought the car in front was coming to a stop or was stationary. A learning process for both of us.

There also seems to be areas where the safety features overlap in their performance when manoeuvring at slow speeds/parking - whether it’s the PKSB,  Front Parking Sensors with Automatic Braking and the Intelligent Parking Sensors (Rear for Objects/Vehicles/Pedestrians).

Toyota have recently released a recall/update for the PKSB as this activates when reversing with a bike carrier/other attached as it thinks the carrier is an object you are going to collide with. 

The update switches off the PKSB system (both front and rear) as it was designed to default to ‘On’ when reverse is selected - this prevents the brakes being slammed on and getting the klaxon brake alert.  

I’ve still got to test this fully and have been advised that you then have to manually toggle the sensors back to on when driving off forwards otherwise the system is still deactivated. It would be better to have only the rear sensors disabled when reversing and the system automatically reactivated when driving off again. The PKSB is very useful particularly when parking in bays and when manoeuvring in tight spaces but it would be a bit of a faff to be expected to toggle it on/off in these situations.

The PKSB update was applied to my car before delivery but I’ve emailed the supplying dealer who is passing on feedback to Toyota. 

It seems that every day is a school day 😬

[Louie]

I am seriously thinking of handing "Clarisse" back to Toyota as I have been sold a car with dangerous behaviour and its a lot of money to be paying for a car with random braking patterns totally outside the drivers control.  The random braking sometimes gradual sometimes violent has not ceased and I am seriously concerned that one day it will result in a rear end shunt.

Today "Clarisse" decided to jam on the brakes and I mean jam when the road ahead was clear with no moving vehicles of any kind or parked awkwardly in the road. The first incident involved yet again a flag mounted on a white pole fixed to the pavement. The  second one involved a car parked on the actual pavement on a grassy knoll. In both cases the ACC was on but that is not how it should work.

I will probably let the dealer collect the vehicle and replace it temporarily with a "loaner" and try and attempt to fix it but I have serious doubts they will.

[CassUK]

I’m thinking ACC is best left off when in urban areas and it should only be used on motorways/autoroutes/dual carriageways and A roads 🤔

[philip42h]

6 hours ago, CassUK said:

I’m thinking ACC is best left off when in urban areas and it should only be used on motorways/autoroutes/dual carriageways and A roads 🤔

That's what Toyota think too...

Use the dynamic radar cruise control only on highways and expressways.

[Devon Aygo]

On 9/18/2024 at 9:40 PM, Louie said:

Now having spent some time trying to master the CHR PHEV controls etc I wrongly assumed I had a 100% mastery of it all.

Every now and then the CHR  brakes suddenly accompanied by three quick beeping noises which I assume is collision avoidance. However non of this makes sense because I have yet to be in such a scenario. This normally happens under 30mph and with parked vehicles present on both sides of the road in particular large vans or largish 4x4's pickups. My impression is that the CHR's crash prevention system wrongly assumes that I am about to hit one of these largish vehicles despite the fact I am a good distance away and positioned on a clear pathway. This appears to be a random event and its beginning to drive me crazy. Has anyone any idea how I can moderate this ?

Are you sure this is not the Proactive drive assist doing its job, PDA does not need ACC on to allow the car to brake or apply steering input, page 330 explains how the car can apply the brakes to slow the car as it approaches objects, it can do this down to very low speeds but is not designed to stop the car, it expects the driver to respond to its input and take action if you don't the the Pre-collision systems cut in with a series of beeps and then emergency brake application.

PZ49X-9A204-EN.pdf

[Louie]

Lee been here many times and after examining my Dashcam my dealer agrees that the my current CHR's behaviour is very unusual and the random breaking should not be happening and the sensors need adjustment ( dealers words not mine).  The breaking occurs when there is nothing ahead of the car but things like flags on a pole waving in the wind set the car off. Anyway my CHR is going in on the 23rd under a recall etc so we shall see what transpires. I previously had a 2023 Excel with similar features and it did not behave in such a fashion. 

[Devon Aygo]

8 hours ago, Louie said:

Lee been here many times and after examining my dashcam my dealer agrees that the my current CHR's behaviour is very unusual and the random breaking should not be happening and the sensors need adjustment ( dealers words not mine).  The breaking occurs when there is nothing ahead of the car but things like flags on a pole waving in the wind set the car off. Anyway my CHR is going in on the 23rd under a recall etc so we shall see what transpires. I previously had a 2023 Excel with similar features and it did not behave in such a fashion. 

A 23 plate would have been the last generation CHR it did not have PDA this was introduced only on the latest generation CHR try turning the set or individual features of PDA and drive on your trigger route

[Louie]

My recent recall fix has not fixed the random braking when using ACC in fact its got worse so sort of got used to it 😒