Got into an accident today due to brake problem =(

I have had my Prius V since October, and am not a "Newbie". I reported the braking problem to NHTSA (and Toyota, who said I was "imagining " it) back in November after experiencing it. I have had the recall done, and still have the problem. This is a Toyota issue, as I have driven a variety of cars with ABS since it became available over 15 years ago, and this is the only car that I have had trouble with. The only "conspiracy" is Toyota's inability and/or unwillingness to fix the problem which I am sure is software related.

 

Thanks!

About the accident conditions:

• Any loose dirt, dust, rubble or gravel on the road surface?
• Pavement cracked or broken up?
• Recent rain or other weather conditions?

Without putting yourself or anyone else at risk, is there any way to get photos of the current conditions? Where photos taken from the accident scene? Does the California Highway Patrol have an online record of accidents at that location?

Send me a PM and perhaps we can collaborate on getting any accident report data including photos. We need to respect privacy so it works better if you can handle 'obscuration' of the sensitive information.

You hit the nail on the head!

I'm technical and diagnosis of problems is my business. But it is hard to get much enthusiasm for postings that are little more than 'venting' without facts and data. So far, the best I've found is:

• washboard road - traveling at high speed, the brakes of the earlier, NHW20 model, are reported to have failed. So far, I can't find a road rough enough to replicate this report but I keep looking (and have found some pretty poor ones!) Sad to say, the OP sold their NHW20 and it was at a detour around bridge work. These conditions are likely to have disappeared just like the pothole I'd found.

After a while, the 'hit and run laments', reports about how terrible it is without offering location, road surface photos, or technical details tend to get really, really old. Fortunately, 'Ecobroker' is not in that pool and should be seen as an example that others should follow.

Serious postings offering facts and data will be respected and follow-ups asked. Whining leads to different responses.

Thanks,
Bob Wilson

 

Maybe I wasn't clear. I think that Toyota does not do enough to impress upon people that it's not a regular car. If anything they program it such that under most conditions it does behave like a regular car. The problem with that is one of expectations.
If I've driven it for 10K miles and it's behaved like any other car should I not expect that in really hairy conditions it'll continue to behave like a normal car especially given that they didn't tell me otherwise? Using ABS may be a rare thing in southern California but during the winter here in New Hampshire it's an everyday occurrence.
I'm NOT suggesting that everyone find a parking lot and do donuts till the system reacts weird. I'm suggesting that Toyota tell new owners that due to the fact that the car has 2 braking systems that it has to cycle through and a drivetrain that is sensitive to slip, brake force may not be predictable on rough or slippery surfaces so drivers should leave extra room under rough conditions.

 

Can you replicate this at will?

If so, where (Google Map or Street View?) Weather conditions? Road surface? How often?

Backup your complaint with facts and data. For example, have you surveyed the Toyota Web site for information about how braking works? Have you reviewed the Toyota sales material about how the hybrid vehicle works?

Propose the exact words you want seen and where. Heck, do it in a posting:

WARNING: Some people post generalizations instead of doing the hard work of following their own advice!
​

Do you want a warning like this in the paint on the driver side door of each Prius?

Please, be part of the solution by showing the specifics, not some generalized, imprecise, and ambiguous lament. Let's diagnose the problem and that means facts and data.

Bob Wilson

 

Paul,

With all due respect, I would have to disagree and say that, yes, people should have to take into consideration the type of vehicle they are operating and what sort of considerations need to be taken into account.

It's no different than someone going from, say a Mazda Miata to a Jeep Liberty. When driving the Liberty, you're not going to be able to pilot it the same way you did your old Miata. There's no "functional design error" with the Liberty -- it's just a different vehicle.

Everything isn't going to drive the same. Your responsibility as a driver extends beyond knowing how to start the car and tune the radio. No, I don't think everyone should be a chassis engineer expert. However, it's incumbent on you, as a responsible owner, to be aware of the differences between the vehicle you drive and others you may have driven in the past. To wit: I know I'm not going to be able to accelerate or corner (or brake, for that matter) the same way in the Prius that I did in my Phaeton.

And, to cossie1600's comment about doing doughnuts to practice stability control, I disagree. Whenever I get a new vehicle, I will take it in an unrestricted parking lot (no poles, parking blocks, etc.) after the first significant snow and throw it into a few skids and panic brakes. I want to know how the car is going to respond in an emergency situation before I find myself in that position.

When ESP first came out I would actually encourage my customers to do the same -- they need to experience how the system operates so that, in an emergency situation, the operation of the system does not provide an additional distraction from their being able to pilot the vehicle to safety.

 

Chris, I definitely agree. I live on a dirt road with a 700' descent over 1 1/2 miles shortly after leaving my house. With new snow, I will often brake hard before get to downhill to know before had what to expect.

With the first snow I will be testing slow braking and fast emergency braking to try to get the "lurch" and see how the car responds and how I should respond.

Chris

 

If you experience any decrease in braking, immediately push a LOT harder on the pedal. (if you overdo it, you can let up - which is better than under-doing it) The friction brakes supposedly have a hydraulic backup, so if you put your foot to the floor, they are supposed to kick in regardless of what the electronics (and some of the "runaway" claimers) say.

The other option is to do a quick "pump" of the brakes - let off completely and quickly re-apply. When the pedal is activated quickly, the computer immediately applies the friction brakes (rather than just regen, as would happen with a more "normal" braking motion).

 

Yeah....sorry; speed for conditions is the cause of this accident. Again, sorry.

 

I couldn't agree more. I've only had my Prius a couple of months, but I have tried hard to recreate this brake problem. While I have managed to get a small "surge" on rougher surfaces, the effect was very minor, and not appreciably worse than similar experiences I have had on other vehicles (my Ford Windstar would do this when the brakes were first applied while coasting down a hill). Certainly it was manageable within the margins for error that I normally leave when driving & braking, and comparable to vehicle specific adjustments I make when driving any of my other vehicles.

In all fairness to the other people that seem to have experienced something worse, perhaps I have not hit circumstances that are severe enough. But based upon what I have tried (short of abusing my car), I would have to be driving aggressively enough (too fast and leaving too little stopping distance) that I would be well beyond what I would consider safe driving practices.

 

I was able to reproduce the brake issue at will at a spot on my daily commute to work where a manhole cover is recessed a bit below street surface just before a sharp curve - I could make it happen any time I was braking moderately as I approached the curve and went over the manhole.

I just got the brake update done Saturday when I took the car in for my 10K service (waiting until now to get it done shows you how serious I considered the issue to be once I knew what it felt like and how to deal with it). I've gotten into the habit of steering around the manhole cover and forgot about it on Monday, but the last two days I have tried to reproduce the brake surge issue. While there still is a very slight/quick sensation of the brakes not working, it is for a much, much shorter interval and corrects itself almost immediately. So IMHO the brake flash has absolutely resolved that issue.

 

^This

In fact, I did the same thing on Friday. I figured I knew what it was, I knew what was causing it, I knew how to repeat it and I knew how to avoid it. I probably waited 2500 miles from the time the recall came out until I got it done.

 

Say what?! Can I get paid for screwing around on PC?!
It is crazy the way folks like to blame the car for their own foolishness and inattention. When I saw 40mph off a ramp with construction and merging traffic I was like "DUH!" My brakes work incredibly well especially in an emergency. Almost ready for my 10k work but did not go running off for recalls because I know how to drive my car. Simple as that.

 

How is it a different car? It still has 4 wheels and a steering wheel. People make it sound like it is the end of world when all you have to do is hit the brakes harder. With the new software patch, the problem is mostly solved anyway. Was it smart for them to design it the way it was? No! Is it the end of the world? Certainly not.

Stupid people are the same reason we have warning labels for everything! Do we really need a label to not eat packaging materials or mothballs? (I saw that in a box today)

 

The Prius is different because usually only the front wheels are used for braking. And by design, if one of those wheels slips then the other wheel stops braking. The end result is NO brakes on ANY wheel. I guess if we were discussing a Pinto, people would blame the driver for putting too much gas in the tank ("You only need enough to get to the next station!" would be the cry).

Sure, I have trained myself to press harder on the pedal when the brakes cut out. But the first time it happen my brain had to process what was happening -- call me "stupid" but in 35 years of driving I had never experience brakes shutting down while I was depressing the brake pedal. Fortunately there was no danger of me hitting anything that time, but I'm willing to accept that others may not be so lucky.

I think the jury is out on the recall fix. While I experienced the problem several times per week from mid-December to sometime in March, I had no problems before then and only two brake failures since (both on the same day). So my Prius also works better, even though I have not had the recall fix done. As others have suggested, I suspect the defect may be related to temperature/humidity, etc., which I think would explain a lot.

 

Let's say, to make up an extreme example, that you regularly drive a Mazda Miata. One day you're driving with your buddy who owns a Jeep Liberty, and you're on a long trip so you switch who's driving and now you're driving.

You come around a corner on the freeway to find everyone at a dead stop. You push the brakes on the car and it starts stopping, but not fast enough. You push as hard as you can - and the steering wheel moves and takes a sharp left into the ditch.

Turns out - the car is designed to take a sharp left turn when you hit the brakes really hard. But you deserve to die or spend 3 months in a body cast and lose some function in your left leg because you didn't thoroughly check out the behavior of the car before you drove it, right?

Of course not. The car shouldn't behave in completely unexpected and unusual manner. When you hit the brakes, you expect the car to brake. When you hit the brakes harder, you expect the car to brake harder.

You're better off with the brakes giving you a longer stopping distance to begin with and behave consistently, than you are with a car that inconsistently sometimes stops in a short distance, and sometimes stops in a long distance.

It is exactly inconsistent behavior that causes accidents. When you hit the brakes normally your car stops in a certain distance. When you hit the brakes but your car is on ice, it no longer does. That's why ice causes accidents.

When you hit the brakes in some situations, the car stops in a certain distance. When you hit the brakes while going over a manhole cover, it's unexpected that the car would stop braking, even if it is only momentarily.

I could write more, I'm just getting tired of writing.

What really irks me about it, though, is:
1. Toyota saying "oh, it's supposedly to periodically stop braking, that's fine"
2. That since the brakes are electronically controlled, there's *no reason* why this should happen. Does it need to switch from the regenerative brakes to the friction brakes? Great! - why doesn't it do that automatically electronically, giving you the same braking power that you would have with the regenerative brakes at that pedal position?

 

I agree. The surprise factor is dangerous.

Even when you know about the issue, you still have no idea when a manhole cover will cause the problem. In my experience, most of the time a manhole cover will not affect braking. BUT sometimes you hit one just right and then the brakes stop. Sometimes I can repeat it on a particular manhole cover, and sometimes I cannot. I prefer ice, it's much more predictable!!!

 

Lol, well I don't prefer ice, and I don't think the brake problem is actually as bad as hitting ice - your brakes do come back. Pushing down harder does seem to work to...unlike with ice!

But it's kinda like ice in that you often think one patch is going to be a problem but it's not, then later you slide on ice you didn't see. It is a lot like driving on ice - you can't totally trust your brakes, even in the summer.

 

Toyota does not say that. We have individuals who express their opinions but we are not Toyota and the fact that no fault was found with one vehicle does not prove anything one way or the other. It just means the parts are there.

If you can reproduce the problem, tell us, tell Toyota, tell everyone how. I'll go the extra mile and try to recreate the problem but without exact technical details, nothing productive is going to happen:

• Where did it happen? (aka., Google map, street view, or other mapping information.)
• What was the road surface? (aka., photos, Google street view)
• Weather conditions or other common factors?
• Does your car have the known fix, SSC-A0B?
• Did a another dealer read out the version to make sure it was applied?

Some of the folks here are pointing out that there are impossible road conditions where nothing is going to stop any car. Others are pointing out we don't see it. But I am not alone in wanting more technical details. If you don't have them, OK, we'll wait until it comes back sometime in the late Fall.

Bob Wilson

 

At least on ice, it's not the cars fault: the brakes try to work (and the ABS helps) instead of deciding to take a nap.