Gen III Prius ~ TURN OFF!

Spoils,

Agreed and I think it just makes us all cognizant of the fact that we have to be careful to ensure our Mats if we install aftermarket are not something that could slide and cause any restriction to the accelerator pedal. Since we (2010 GEN III) have the push button start it just makes us more aware of how to handle an emergency situation unlike any other, only that we don't turn the KEY OFF.

Push and hold the Power Button for 3 seconds is the key commentary based upon a call to the Toyota Customer Service as well. It's just something good to know.

Enough said I guess....life is a learning process all the time.

Thanks!

 

Thanks, Rokeby. I have a better idea now of your concerns (the edits to your earlier post make it much clearer to me).

Yes, this is a thread started by a one-poster, but I haven't seen anything really trollish in the post itself. While the topic has the potential to be inflammatory, I think the OP's approach was fine and the topic commendable.

In the end, I hope many people are able to learn some basic operational things (about their cars!) from this whole event.

(Of course, hobbit's experience just blows one's mind! Do people not only know the purpose/use for/of low gears, but they don't know how to engage them in their own cars?)

 

I usually think of 'trolls" as someone undesired on this site, usually just dropping in to cause discord. In this case, even if it is only one visit, they brought forth a concern (fear may have been their intent) that took several responses to come to an understanding of the issue. Did anyone new to the Prius learn how to shift to nuetral while driving? I think so. Regardless of their intent, it is good information imho.

 

My first relief was the absence of a "Consumer Affairs" source. For good measure I checked the "Consumer Affairs" web site and the whole tone has changed ... it looks like they are selling insurance, not lawyer services. But as recently as last fall, we were still seeing periodic reports of 'runaway Prius' including one thread that instead of slamming, we treated as 'another problem to diagnose.' Happily that thread ended when the OP sold his Prius (with the all weather mat) and we've not heard a peep since.

We've had rascally posts in the past but I'm hesitant to call them troll until we've had an exchange, a dialog with them. Some rascals are just ignorant and treating their postings with the facts and data is usually all it takes. A few rascals take a little longer dialog but this can illuminate the scientific method ... what it takes to learn. But when the rascal reverts to their original complaint showing no evidence of learning, well then the right thing is call 'troll.'

In this case, the rascal posted something about the Lexus, not a Prius, so the posting and thread are actually in the wrong forum. Relocation to the Lexus forum would be an excellent response. Also, the rascal hasn't come back, not that they have to, but rather it suggests a limited commitment to the Prius or their original question has been answered. This is OK too ... a hit and run rascal posting that was answered with facts and data.

Now if the rascal would come back and report, "I tried ..." and shared what they learned, I wouldn't call them troll. I would call them informed. But the basic problem is the original posting was about a Lexus, not a Prius.

But one part of this report has struck home, my wife's behavior driving her car without me. She still expects the engine to make a noise when she starts the car and hasn't really understood that she needs to turn it off. So I'm thinking about a little 'after market' assistance. If I can find the "READY" signal and driver side door open switch:

• READY goes from OFF to ON - play the race car noise for 15 seconds ... just long enough to lose its cuteness.
• driver door open while READY is ON - play the race car noise in a loop and louder if the READY is ON and the door is then closed. Certainly more useful than those beeps. <grins>

Bob Wilson

 

Um... In Driver's Ed, we were told that if the accelerator gets stuck:
1. pull up on it with your foot
2a. if that doesn't work, shift into neutral
2b. or you can kill the engine, but you'll lose power steering and power brakes

I assumed that everyone knew this.

 

Bob,

I think I agree with most everything in your post, except for the statement above. (Well, I'm not really going to comment much on the "after market assistance" plan you have for dealing with your wife . . .)

I think the idea was to find out if the same deal holds true for a Prius with a Power button as for a Lexus with a Power button (assuming, of course, the Lexus at issue had this setup -- I don't even know if it was a hybrid).

Hmm. Maybe I don't even disagree with you at all -- except that I can't comment on the wife thing!

 

I agree, I think this post was helpful. The OP provided solutions to the problem... What troll would do that? Anyway, I think they are good tips. Never having needed to do any of this before, in a panic situation it might not have occurred to me to try these things.

 

The accident was real enough but I still do not think it should be used for everyone to go out and point there fingers at Prius as being "dangerous". It just shows a continued level of misinformation and ignorance.
I walked into work after this occurred and and the guys who watch our forensic patients asked if I was afraid to drive my car because of the accident. I informed them that that the car involved was NOT a Prius and asked them if they thought about how dangerous their SUVs were every time someone died in a roll-over accident!

 

What disturbs me about the accident (and my only concern with the OP is that they want a solution to an accident they did not document) is that his brakes failed.

So far as I know ANY car can be stopped with the brakes (in a long distance) if the engine is floored. However, what if the driver made the mistake of only using the brake to slow the car, and keep going? Given time, the brakes would fail, (Brake fluid boiling, pads wearing out, etc.) and then he has nothing. To solve this with his brakes he HAS to come to a complete stop and stay stopped.

I think shifting to Neutral is best, pressing Power is next best, a stopping completely with the brakes is third best, but riding the brakes to slow down is a horrible plan.

 

Everyone has assumed that because the driver was a CHP officer he would be better able to handle this emergency. There are a lot of other factors here.
1. Car is a loaner....condition, unfamiliar with vehicle
2. The 125N has a choice of going to a Tstop at a fairly busy surface street or swinging on to the 52 west. He stated that they were 1/2 mile from Mission Gorge....the smoother turn to 52 should have been an option.
3. No one will ever know everything that went on in that car. We all simply have to be alert when driving and know our cars. I avoid taking loaners but if I did I would definitely spend some time familiarizing myself with the vehicle.

 

FYI: if you buy/rent a new BMW (from series 1 to 7) you get a "start" button like a Prius. So, unless you have a mechanical gearshift with a clutch pedal, you're "out of luck", so to say.
Renault has the same "start" button on most mid-high end cars. And other manufacturers are following.

That the accelerator pedal can get stuck, e.g. due to mats, it can happen on *any* car.

The worst thing one can do on *any* car is turning off the engine - *all* cars have power steering and assisted brakes (and ABS!!! and VSC!!! that will NOT work if you turn the engine off): the only thing you would be left would be the pedal (parking) brake (like in the Prius, Mercedes, Lexus)...
I would train myself to put the car in Neutral, and start breaking it with the pedal brake until I can do that "automatically". I am, for one thing, still used to the hand brake in the middle - using my left foot to brake will take a lot of time. Left foot for me is only "clutch".

I have never heard or read that in the EU a car started spinning out of control due to a mat, or accelerator pedal going bezerk or not being able to break it to stop. BTW: you can have the same problem if you drive with flip flops....you want to have an accident? drive with flip flops (or anything similar). I think it is even illegal to drive in flip flops in most EU countries...

The brake pedal, BTW, is also called "emergency brake" to stop the car, even if it accelerates out of control.
Brakes brake more than what the accelerator accelerates...

So I don't see where the problem is with all this matter, the Lexus crash and everything in between.

How to turn the Prius off? you stop it someplace and press the "off" button once. End of story. Anything else, done in any other case with the on/off button will mean big trouble. A Prius (or any other similar on/off button car) turned off while moving, would really be an uncontrollable car - no question about it!

 

The majority of posts to this thread assume the driver did not take the correct action to stop the car and that a mat was the probable cause of the accident.
Consider that it was not the mat and that he did do the right thing but could not stop the car.
What if an error occurred in the ECU (or whatever controls the engine/drive) causing the drive mechanism to go to full throttle. Could such a failure also prevent neutral being selected or the power being turned off?
If the part about flames coming from the brakes is correct then the brakes were working. Are we positive that the brakes can stop an accelerating Lexus travelling down hill?
I once experienced a drive switch off in my Gen 2 Prius while backing out of my drive. I would not say it was a frightening experience but it certainly caused me some anxiety as the back of the car was sticking out into the traffic.
A complete failure as experienced in the crashed Lexus would cause most drivers some anxiety to start with and as they worked through remedial actions that did not work, panic would more than likely set in. Was this the stimulus for a back seat passenger phoning 911?
We will probably never know the truth but what readers of this thread are really interested in: Can the Prius ever have an electrical/electronic fault that can cause an unstoppable runaway condition?
This question needs to be answered definitively by someone in the know and not guessed at.

 

In a Motor Trend test, the 2010 Prius took 1320 feet to get to 77 MPH, yet it can stop from 60 MPH in 120 feet. The brakes on any car are massively more effective than the engine.

Will the braking distance lengthen if the engines and motors are going full blast? Yes. But the brakes are about 8 times stronger.

What IS vital however is to come to a complete stop as quickly as possible, if you only try to slow the car and continue on your way, eventually the brakes will over heat. This is a driver decision, not an electronic decision.

 

Perhaps because there is history of mat induced, run-away accelerations and interference with braking.

A hypothesis like this needs some way of being tested. Any thoughts?

Do we have enough information to identify exactly the route? We could then use Google Earth to calculate the grade and the amount of energy gained going down the proposed grade.

What is a "drive switch off?" Was there a diagnosis? Has it returned? How long ago?

The problem is "ever" is one of those words that suggests an infinitely large testing set. It becomes an untestable hypothesis.

But it is a question that can not 'ever' be answered. This is not a semantic exercise but a practical problem of spending time and resources. The hypothesis is too broad, too imprecise. So the right answer is:

If someone is afraid of the Prius, don't buy it or if already owned, replace it with something else. Life is too short to live in fear, uncertainty and doubt. But for empiricists, scary stories are not a substitute for facts and data and the scientific method.

Bob Wilson

 

May not necessarily be his fault. One thing I have found with this forum is that automatic thread subscription and instant emails are NOT the default setting. Most of the other forums I'm in have auto-subscribe on by default and at least a weekly email update default.

Back on topic.

Brief and to the point. Glad someone posted the 3 second power button rule since I haven't read OM yet.

If the accelerator is stuck and the car is in neutral, how does it respond? I would assume the ECU knows it is in neutral and doesn't rev the engine.

I have the all weather mats. I couldn't easily remove from the car to clean them. The driver side mat is somehow clipped into place so it shouldn't be able to slide forward onto the brake or accelerator.

 

I will try and answer the replies to my post.

While this may be so, what effect would the vehicle's inertia have on stopping distance, especially if the car is going down hill?

The drive to the wheels ceased and the car came to a stop. This happened once more that 2 years ago and from memory went undiagnosed. I posted the event and the consensis was that the cause had to be finger trouble because the Prius cannot do this by itself. How can finger trouble cause a reversing Prius to lose drive to the wheels?

While I agree with what you say, I am not afraid of my Prius. What I am saying is that as a driver an event that you have no control over would be quite scary.
If a computer corrupts data can this corruption flow on to other computers within the Prius?

 

I was assuming the vehicle had inerta in the Motor Trend test, without it they should have been able to stop in Zero Feet. You earlier wanted hard facts, not theory. I can show the effects of braking downhill in general, but I have no hard facts that anyone has done the test in a Prius. (I live in the Delta so it would be a 50 mile drive to find a hill, and that would not be big enough to do 60 to 0 tests)

Here is data for semi trucks, notice that they take MUCH longer to stop, even on level ground, but the effect of uphill and down hill are not that large.

http://www.iowadot.gov/design/dmanual/06d-01.pdf

The Prius is so much less massive, I would expect the differences to be less.

Fundamentals of Transportation/Sight Distance - Wikibooks, collection of open-content textbooks

 

Agreed -- also, a first-time poster in any forum might not remember how to get back to the forum/post. I have sometimes posted a question or comment in a forum that is new to me and, if there's no automatic notification, had the hardest time finding my post. After some time, I might just forget about it altogether.

 

Two years ago and even today, I tend to avoid discussions about a vehicle that I don't have direct, hands-on access. So I'm pretty much up on the NHW11 (2003) and ZVW30 (2010) but we skipped the NHW20 model. But I'm wondering if the other posters might have used the term "parking pawl" versus 'finger?'

Did you ever get one of the maintenance manuals and read up about a parking pawl?

Yes, things can break and sometimes those failure pass on to other parts. For example, an "O" ring in a solid rocket booster can fail and a jet of hot, rocket exhaust burn a hole in a tank of rocket fuel. That rocket fuel can then ignite and explode tearing a spacecraft apart and killing all of the astronauts. But we know this happened because of photos and inspection of the debris along with lab testing and analysis of earlier failures found during solid rocket segment refurbishment.

A hypothesis without testing or supporting facts and data is not terribly useful. Worse, there is a long history of Prius skeptics making horrible, terrible, life-threatening hypothesis with the flimsiest of evidence or even making stuff up. That is why many of have gotten more adept at looking for empirical data, facts and data, to see if these hypothesis have any merit.

Now if you have some facts and data that shows a Lexus computer corrupted data and passed it on to other computers and caused this accident, bring it out. Alternatively, construct an experiment that replicates this failure. Then get a Lexus and perform the test. Alternatively, get the Lexus parts and set them up in a lab to document a failure mechanism. The hard work is testing ... getting the facts and data.

So join the reality based folks and do the experiment ... get the parts and demonstrate the problem. Words typed on a screen or just noise without backing facts and data.

Bob Wilson

 

Sorry, I did not express myself very well. I was thinking of the additional weight in the vehicle with a driver and 3 passengers. One wonders what was in the trunk. In other words the car could have been heavily loaded which would make it all the more difficult to stop because of the inertia.
That aside, if the brakes were on fire why did they not stop the car? Surely the driver would have put on full brake to stop the car not a small amount just to slow it down. Logic says he would want to stop a runaway vehicle.