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Any 2010 Prius owners here can share experience about "inconsistent brake feel"?

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Posted by DA on February 10, 2010, 3:05 am

I own a 2009 Prius and have owned a 2007 Prius before. And several other
cars before that which had ABS in them. So, based on my personal
experience with ABS  I cannot wrap my head around the description of the
problem as posted on Toyota's press site:
"inconsistent brake feel during slow and steady application of the brakes
on rough or slick road surfaces"

Who would seriously expect a "consistent" feel on a "rough or slick road"?
Isn't this a driver's responsibility to contain a safe speed according to
the road condition? I have also heard about a feeling of delayed braking
after the pedal is depressed which would be a bad thing indeed. However,
what kind of delay we are talking about? Is it really 1 second as the dude
from The Detroit Bureau was saying on the air today? I mean, really, a
second delay is crazy and I don't think it is really what's happening.

So, we've heard a lot of talk about it lately but can someone describe the
experience first hand?

Also, The Detroit Bureau website is hinting at a possibility that earlier
Prius models may be affected which is a total bullshit. It appears that
there are at least some unfounded allegations surrounding the issue so if
someone can share a first hand account, it would be greatly appreciated!


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Posted by Daniel who wants to know on February 10, 2010, 6:57 am

The problem is thus: The Prius reduces regen braking down to coasting levels
or cuts it off completely and switches to friction brakes whenever any of 4
things occur, 1. The speed drops below 7MPH, 2. The ABS activates due to
slick or uneven surfaces, 3. When you brake too hard or suddenly (panic
stop), and 4. You "shift" to neutral.  Unfortunately the car has a slight
"break before make" behavior regarding the transition and as such in the
2010 for about .8 seconds the car coasts between when the regen is switched
off and the friction brakes are applied.  Due to the way our inner ear works
for some people this can feel like the car is actually accelerating instead
of just coasting. This is not a delay between when you first press the pedal
and when actual braking happens.

BTW I do not own a Prius and my hands-on experience with them is limited to
about a 10 minute test drive in Lawton, OK but I am an "armchair enthusiast"
with hopes of owning an '05 or '06 model in either Millennium Silver or
Seaside Pearl someday.  I do not like the ZVW30 and am indifferent about the
NHW11 hence the want for an NHW20.

Posted by greenpjs on February 10, 2010, 1:54 pm

On Wed, 10 Feb 2010 00:57:57 -0600, "Daniel who wants to know"

I own a 2010.  The above description sounds reasonable except I do NOT
feel a period of coasting when slowing down normally throught the 7
mph range.  I will guess that the problem occurs when the ABS function
is activated during that transition period.  That's why most people
don't experience the problem.

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