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[Shackeng]

An item in yesterday's paper reported a 911 call from a passenger in a 2009 Lexus ES350 to the effect that....' the accelerator's stuck, ....there's no brakes.......we're approaching an intersection' etc. The vehicle subsequently crashed, killing the occupants.
Not knowing the type of car, I find it hard to understand that someone had time to make a phone call, and yet the driver - an off-duty Highway patrol officer - was unable to either switch off, apply the parking brake, or select neutral, during that time.

[Marks DTM Calib]

Its an interesting one.

I cant say I know the answer but, I wonder if the vehicle in question had an auto handbrake plus a start/stop button.....or even if it had an ignition key....

Maybe all these new conveniences are a step to far.

I have never been a fan of auto handbrakes, the fact you have a mechanical lever, and a cable to the rear is a little more comforting under such an emergancy scenario.

[Kevin Wood]

Its an interesting one.

Indeed. I have had a stuck throttle and it's no drama if you have manual control, and some common sense.

Dip the clutch, off with the ignition and coast to somewhere safe to stop.

I suspect either the manual control, or the common sense, was missing.

I must admit, a manual switch that kills the ignition and a physical linkage to get the gearbox into neutral are things I'd be loathed to be without, and I can't see the point of auto handbrakes at all.

Kevin

[Shackeng]

Its an interesting one.

I cant say I know the answer but, I wonder if the vehicle in question had an auto handbrake plus a start/stop button.....or even if it had an ignition key....

Maybe all these new conveniences are a step to far.

I have never been a fan of auto handbrakes, the fact you have a mechanical lever, and a cable to the rear is a little more comforting under such an emergancy scenario.

Agreed, all possibilties to explore, but it should be possible to select neutral.

[Chris_H]

I guess this is the incident in question.

Having a CHP officer with all his family on board makes it seem he would have tried all the obvious, although he may not have been familiar with the vehicle.

Ironic that he should hit an Explorer which has a similar reputation.

[Shackeng]

I guess this is the incident in question.

Having a CHP officer with all his family on board makes it seem he would have tried all the obvious, although he may not have been familiar with the vehicle.

Ironic that he should hit an Explorer which has a similar reputation.

That's the one. I wonder what happened to the fail safe?

[feeutfo]

not sure they where killed where they? from what i saw on the news there was a pic or a video of a surviver standing by the wreckage.

Certainly was a crash non the less, i put it down to panic, i've always encouraged the Mrs to play with the car a bit in poor conditions, in the rain and esp. snow i brake test regularly to check how much grip there is or isnt before i get to the junction. She hated it at first and used think we where going to die just because the car skided or the abs engaged. Total over reaction and beyond logical thought. Now though and esp in the last week of the snow she is far more confident and understands more of the cars performance level, so no more panic to a point.

I remember a similar issue with cruise cotrol on some american suv, and the accounts given where vastly differant according to driver experience. ie the little old laidy simply piled into the back of the next car, where as the guy who owned a sports car with motor sport experience simply pulled the key out. Panic, imo.

[feeutfo]

I guess this is the incident in question.

Having a CHP officer with all his family on board makes it seem he would have tried all the obvious, although he may not have been familiar with the vehicle.

Ironic that he should hit an Explorer which has a similar reputation.

ah certaily where killed. Different story maybe.

[feeutfo]

although the artical above mentions some double redundent fail safe feature, what ever that is?

[Kevin Wood]

although the artical above mentions some double redundent fail safe feature, what ever that is?

If it's anything like most drive-by-wire systems, it means that the throttle pedal position sensor and the throttle plate position sensor both have two potentiometers with different characteristics so that the two voltages reported to the ECU for any given throttle position are different.

The ECU can then compare the two and make sure that they both correspond to the same position. If not, it goes into limp-home. The idea being that failure of a single pot, wire, supply, etc. will be detectable by the ECU and not result in a roller-coaster ride.

Of course, if the problem is mechanical and the pedal physically gets stuck to the floor it doesn't help. :-/

Kevin

[waspy]

So that's progress :-?

I used to be an Undertaker in my twenties & we used to use stretch Granadas. We had one with a sticky pedal & if you jammed it hard down to the floor it would stick
I dropped the Mourners off at their home in Smalley & i pulled away from the side of the road only for a car to come flying around the corner a second later, i booted it & the pedal stuck. There was i in this dirty great Limo with a 2.8 V6 flying up the road trying to lift the pedal with my shoe
I managed it, but i often wonder what the Mourners thought after they'd had a nice sedate drive from the Crem

[Dishevelled Den]

On the Prius there is a transmission brake - electrically operated via a button on the facia, engaging this at rest automatically places the transmission into neutral, there is also a mechanically operated foot parking brake. 

There is no ignition switch - simply a slot where the transponder is inserted.  The systems are energised by means of a start/stop button.

The transponder is locked into position whenever the car is in motion – whether this lock is sufficient to prevent forcible extraction when in motion, and what effect that would have on the vehicle I don’t know, as I wasn’t brave enough to try on my trip to the shops just now.

The transmission can be shifted into neutral when the car is in motion.

The braking, steering, transmission and throttle systems are all electronically controlled or assisted so if there is an electrical fault, I could foresee problems in bringing the car to a safe stop.

[Shackeng]

On the Prius there is a transmission brake - electrically operated via a button on the facia, engaging this at rest automatically places the transmission into neutral, there is also a mechanically operated foot parking brake. 

There is no ignition switch - simply a slot where the transponder is inserted.  The systems are energised by means of a start/stop button.

The transponder is locked into position whenever the car is in motion – whether this lock is sufficient to prevent forcible extraction when in motion, and what effect that would have on the vehicle I don’t know, as I wasn’t brave enough to try on my trip to the shops just now.

The transmission can be shifted into neutral when the car is in motion.

The braking, steering, transmission and throttle systems are all electronically controlled or assisted so if there is an electrical fault, I could foresee problems in bringing the car to a safe stop.

That's why I am puzzled, in my experience American marketed cars invariably have a foot operated parking brake, and facility to shift into neutral. No doubt the authorities over there are also scratching their heads over this one.

[Marks DTM Calib]

The question is, are these foot operated brakes (remembering that this is not an American car) now truely mechanicaly connected to the brakes or does it go via some logic function that thinks....thats much to fast and I am not applying the brake pedal.

If so, then there could be a failure in the system design.

Of course, the brakes may have been so hot through trying to stop it that they were no longer working.

Why could they not put it into neutral....no idea on that one.

[Dishevelled Den]

On the Prius there is a transmission brake - electrically operated via a button on the facia, engaging this at rest automatically places the transmission into neutral, there is also a mechanically operated foot parking brake. 

There is no ignition switch - simply a slot where the transponder is inserted.  The systems are energised by means of a start/stop button.

The transponder is locked into position whenever the car is in motion – whether this lock is sufficient to prevent forcible extraction when in motion, and what effect that would have on the vehicle I don’t know, as I wasn’t brave enough to try on my trip to the shops just now.

The transmission can be shifted into neutral when the car is in motion.

The braking, steering, transmission and throttle systems are all electronically controlled or assisted so if there is an electrical fault, I could foresee problems in bringing the car to a safe stop.

That's why I am puzzled, in my experience American marketed cars invariably have a foot operated parking brake, and facility to shift into neutral. No doubt the authorities over there are also scratching their heads over this one.

It's a strange one no doubt.

I'm not sure if the parking brake would be person** enough to bring the car to a halt from speed all the same.

I would have thought however that the main braking system on the car would have functioned albeit without assistance - perhaps in this case the driver didn't have the time or space to manoeuvre his vehicle away from danger.

Possibly it was a simply a case of panic in rapidly unfolding circumstances.

In any case it's a most unfortunate occurrence for the occupants of the vehicle and their families.


**
In deference to our beloved Sister in Christ, Harriet Harman -
MP for Camberwell and Peckham, Deputy Leader of the Labour Party
Leader of the House of Commons, and Minister for Women and Equality - and her proposed Equalities Bill.