BRAKE FAILURES ON 04+ PRIUS

[djasonw]

I know this sounds like doom and gloom, but the aholes are at it again on Edmunds. Someone started by saying that his brakes failed and he nearly had an accident. He is claiming that it is related to a software issue. Can someone please tell me what redundancies are built into the Prius with respect to the brakes?

[hobbit]

Got a specific URL?
.
_H*

[galaxee]

brake backup power supply kicks in if all else fails.

i smell a rat.

[DieselConvert]

I selected "N" while at about 30 mph and made sure that the MFD showed no ICE and no regen, then applied brakes to see if there was any difference in the pedal feel or brake sensitivity over the braking in "D". I think the pedal travelled a wee bit farther before braking, but the braking at that point felt the same, to me.

Can some technician criticize my method, or verify the results?

[Jerry P]

Sounds like another GM 'expert' over at Edmunds. I quit checking over there a while ago as there are lots of kooks and bashers.

I would think that with both the regen units and the regular brakes, the Prius is one of the safest braking systems around.

[saechaka]

on a side note, i have an early 05 that is in line for the recall. i've noticed lately that my brakes seem to depress too far. when i press the brakes all the way down and release i hear creak type sound. as if something is not lubricated. hopefully it's not too serious and under warranty.

[hdrygas]

Originally posted by DieselConvert@Nov 10 2005, 05:53 PM
I selected "N" while at about 30 mph and made sure that the MFD showed no ICE and no regen, then applied brakes to see if there was any difference in the pedal feel or brake sensitivity over the braking in "D".  I think the pedal travelled a wee bit farther before braking, but the braking at that point felt the same, to me.

Can some technician criticize my method, or verify the results?

[snapback]153863[/snapback]

I will try that. As I understand it from Prius NCF the back up capacitor battery kicks in and allows the hydraulic brakes to work.

[efusco]

It's a triple redundant system comprised of the standard regenerative braking system, the charged capacitor system and a standard hydrolic brake system as on any conventional vehicle.

For a brake failure to occur would require the simultaneous failure of all 3 systems.

[hobbit]

If you're in Neutral, there's no regen. Only physical braking,
but it's still controlled by the computer and the rats nest of
solenoids. Yes, braking feel will be different in that case.
.
Braking in N has its uses, too -- for the poster who's noticing
the weird noises or klunks. This topic came up elsewhere around
PC not too long ago, in fact. For a longer piece on braking
oddness and using neutral to fix it, look near the end of
http://techno-fandom.org/~hobbit/car...s-log/003.html in which I
went through my own discovery process.
.
Found the earlier PC topic:
http://priuschat.com/index.php?showtopic=11858
.
_H*

[Jonnycat26]

Originally posted by djasonw@Nov 10 2005, 08:21 PM
I know this sounds like doom and gloom, but the aholes are at it again on Edmunds.  Someone started by saying that his brakes failed  and he nearly had an accident.  He is claiming that it is related to a software issue.  Can someone please tell me what redundancies are built into the Prius with respect to the brakes?

[snapback]153844[/snapback]

I hate to be doom and gloom too, but this has been reported to the NHTSA (if you search), so it has to have some basis in reality. And you'll find topics here where people talk about brake 'slippage'. One guy did rear end another car as I recall.