Brake fix didn't work!!!!

perhaps some are feeling different effects of the brake pause than others. I regularly experience it and it is usually no big deal. However, there have been two occasions where it was a big enough deal where if an obstacle was in front of me, I would have a hard time not hitting it, and the entire effect was very unsettling.

My guess is that many of the 'no big deal' crowd hasn't experienced these moments.

 

I'm not in the "It might of happened but I didn't notice it" group, as I know my Prius like the back of my hand and am very sensitive to the way it drives. I know it well enough to know that the computer allows more torque from MG2 the higher the SOC is. (Now confirmed with the XGAUGEs I made.) I've played around with the ABS, stability control and brake assist tons of time while driving up on Mulholland and twisty roads with it, and it's always behaved just as I expected it to. I am sure I have never experienced this particular brake issue.

From the sound of people's explanation of how it feels, it seems like you can't miss it, especially as it's freaking so many people out.

It just seems like some cars are more prone to it than others.

 

Must be the same contractors used in Huntsville AL.

Bob Wilson

 

On defense of FullOGas, this is exactly what the brake phenomena feels like. It happened to me twice. On both occassions, I looked behind because I could have sworn someone bumped my car. Seeing no one behind me, and having just driven over a very bumpy area, I realized it was the brakes. My head did not slam into the headrest, but the sensation of a rear end collision was quite intense, enough to get my adrenaline pumping.

 

If you say it happened, I believe you. Just trying to figure this out.

For a feeling of brakes slipping, all that has to happen is for the brakes not to work for a bit of time. OK. This is not what you are feeling.

For a feeling of being rear ended, a jolt of energy has to be applied to the car. Right? Correct me if I am wrong.
I presume you did not hear a bang as in a collision. Right?
Did the engine or electric motor speed up? Did you get unintended acceleration? Did you hear the engine rev? It is likely you did not have time to monitor all these things so I was just wondering.

 

I'd say that 60K miles is what you can expect, unless you don't mind driving around on worn struts/shocks. (Fairly subtle difference between good and worn.)

 

I wonder how many folks that feel this sensation have their tires pumped way up. I know that when I had mine inflated to about 42, it felt as if the tire bounced along the rough spots on the highway. When the tires seemed to bounce, the loss of surface contact from the tire seemed to make the VSC and ABS systems very active. We must ask ourselves if the possibility of overinflated tires in order to boost mileage could be adding to the sensitivity of the brake phenomenon. My tire pressures are back to their normal range, and we still average between 48 and 52 mpg on a 2005 prius with 127K miles. (p195 / 205 / 15's) new costco Primacy MXV4's

Just like HTML spinmeister, I will test road conditions from time to time. Trying to make the vehicle slide or slip on smooth and or wet uneven pavement gives me the practice feeling of what to expect when these systems engage for real. The overall result of this practice on the wet winter roadways, is to slow down, which makes my mileage go up. It's a true win win for me.

 

This is true, but the two are essentially the same feeling. To the human butt accelerometer, any difference will be subtle. This is the core of the debate: two people can feel the same sensation but describe it differently.

For example, what does blue look like to you? We can all agree that it is a cool color, but do you think you could describe it well enough that a blind person could picture it?

Tom

 

Ditto!!! It's happened to me 3 times exactly as you described. Could I live with it ? Yes. Do I want to ? No.

 

To a blind person, I would say light having a spectrum dominated by energy with a wavelength of roughly 440–490 nanometers. Just kidding. I see your point.

Totally unrelated to your posting or this discussion, I will take an indefinite break from posting.

 

This Thread (like so many others) takes detours, forks in the road, and U turns.

Back to the OP and title---

DOES ANYONE HAVE OBJECTIVE EVIDENCE THAT THE BRAKE FIX/SOFTWARE UPDATE DOES NOT WORK????
It probably would be beneficial to keep this thread faithful to the Topic. Don't mean to come across as "holier than thou" - I take part in Thread diversions too....

 

First, it's important to define what "does not work" mean? The potential fix could be it's completely eliminated or it's simply reduced to the less noticeable and intrusive Gen II's braking characteristics. If it's the latter, a new Prius owner is going to conclude it does not work whereas a someone who's owned a Gen II is going to say the fix did work and now feels like the Gen II.

 

hockeydad, I'm surprised at you!

You had seemed so enthusiastic about the prius, and now you're saying you'll sell it. I'm sorry the car didn't work out for you.

For my part, I wished the brakes worked differently. I gather from this thread that ABS engages much more frequently on this car than a conventional car, and that's the reason why the braking seems to cut out at times. I do like the car, although I am not sure I will keep it for as long as (100,000 miles plus) I normally keep a car.

 

Re: hockeydad, I'm surprised at you!

Mostly, my reasons have nothing to do with the car itself. For me, anyway, the brake issue is a JOKE. Not concerned in the least. I do believe, however, for $30K, the car appears to be cheaply made, but not a huge issue with me (otherwise, I wouldn't have bought it in the first place). But I'm use to European sedans, so to me, the Prius doesn't quite meet the same mark when it comes to workmanship and materials. However, my main beef concerns Toyota, and the way they delt with their customers.

On a positive note - I bought the car (primarily) for mpg's, and in this regard, it has delivered, and then some. In over 7K miles, I've only had two tanks less than 50mpg using the ECO setting (and that's measured mpg's, not what is displayed). Even using the PWR setting 100% of the time, I still get 46mpg-50mpg. Remarkable. I am very happy with the mileage i get, and also, not having to use premium gas (as with all European sedans). Finally, having a hatch-back also provides nice flexibility in utility of use (e.g., can fit our two Golden Retrievers for short/medium length trips).

We've had a ton (no, multiple tons) of snow where I live, so haven't gotten around (yet) to see what other car i might get, and to see what I could get for my G3. If i can't work a good deal, I probably will continue to drive the G3...or turn it over to my wife (she really wants a Prius).

 

Re: hockeydad, I'm surprised at you!

Sounds like the best plan Doesn't lose you anything when 'trading' and she gets what she wants.

 

Are you talking about where YOU live or in general? I'm at 100K and there is nothing wrong with my struts/shocks. And the potholes in Vermont make the ones in LA look like a newly paved road. Of course, I DO try to go AROUND them

 

I totally disagree. That is one of the BEST ergo dynamic designs that started in the Gen II Prius. Why? Because it does not matter what 'gear' you are in when changing to another. Drive is ALWAYS left and down. Reverse is ALWAYS left and up. Not a millisecond of thought given to 'which way do I have to push it to get to the gear I want'.

Think about a 'traditional' console mounted automatic transmission. From P to D is back 3 (or oops, a bit too far to 2), from there R is forward 2, etc. And you might have to push a button before you can move it. Add in the notched ones - from P to D is right then down then left then down. How STUPID is that??

With a Prius, you don't even need to put it in Park before you turn the car off, it does it for you. I don't think of that as hubris but good design meant to make driving less 'work'. Maybe it wasn't done that way out of generosity but fear people might forget to put it in Park, I don't know, but I LIKE IT A LOT!

 

Geez I hope they don't treat recalls that way. For my money, the floor mat 'recall' is a TOTAL red herring. I have both carpet and winter mats (obviously only using one at a time) and neither comes close to touching the accelerator pedal. I really don't know why Toyota allowed themselves to be dragged under the bus with this one.

Should I take my car to the dealer, they better not take out my PROPERLY installed OEM floormats. They seem to have been designed to fit THIS specific Toyota model

 

IMHO you are 100% correct. It didn't freak me out, but it is definitely different than you would expect. I can understand how it would freak me out under other circumstances. btw: I know it is OT but what X-Gages are you using.

As a possible explanation, the NHTSA originally was talking about 37K cars not all of them. We now know there are 3 versions of braking software out there before the fix. So it may be just one of these versions. Toyota also commented that weather and road conditions matter. So even if you have the one bad version you may not be braking at the right pressure/time in the right conditions for it to happen to you.

Having seen many problem reports on other types of equipment, there are some other possibilities if the fix does not work on specific cars. There may be sensor or motor defects on just that car or a few like it. with 270K cars in japan and the us, a 0.01% defect in sensor would still affect 27 cars. There may be other bugs that only show themselves in a few instances. That is why for good customer service toyota should take these seriously. I do not know about toyota but other companies have computer systems that track parts to vehicles and they can use that information to check if other vehicles with the same lot also have the problem. Then again it may just be the way the abs works and the driver needs to understand it. We do not know this until someone checks it out.

The good news. Toyota has found at least some of the bugs. They have shortened the distance required when abs system is used. They have improved the software to be more consistent and faster when switching from standard to anti lock braking. This should improve the braking of the cars without affecting the fuel economy.

Props to those who reported the problems and helped Toyota recognize the problem and get us a better brake feel and a safer car.

Boos to those that labeled those reporting problems as trolls, cry babies, whiners, bad drivers.

Props to Toyota to fixing a problem that they could not find in testing in a timely manner.

 

I would like Rick, and any other Gen III owners who also own(s)(ed) a Gen II, to do the 'before and after' tests and compare to the Gen II 'feel'. As I do not have a Gen III, I can not compare but I know the 'feeling' in the Gen II and can make it happen any time you like on specific pieces of road. I can also make it NOT happen any time you like in the same places by braking differently (ie not passing through the regen to friction speed braking while over the bad piece of road).

Is it really that much different in the Gen III?
Is it different between one Gen III and another?
How much different is it from the Gen II?

hockeydad said: "I'd say many Prius owners are way below average when it comes to knowing anything about their car, how it works, or even how to handle it."

This is likely more true about some of the more recent buyers. Certainly not true at all of those who bought in 2004/2005. The sales people knew SQUAT about the car and places like PriusChat were where you went to find things out. Heck, even when we got my wife's '06 the lady knew almost nothing.

Still, I would have to take exception with such a general statement. I think that people who have a desire to know about their vehicles make an effort to learn, those that don't have a desire don't make the effort. It doesn't matter what they drive.