NHW20 brake pause problem?

Yes gen 2 has a similar problem that when there is a bump or a slippery patch on the road, the re-gen braking would cut out and it seems to require more brake pedal pressure to achieve the same (now only frictional) braking force as before the re-gen cut out. (thus giving the driver a sensation of braking loss/failure or even "unintended acceleration".) I can dig up some data later.

 

Hybrid tax? Holly crap, I never knew about that one. Do you get a tax credit if you can prove that you polluted a river or something. Or maybe show receipts to prove you sprayed a enough cans of cfc aerosols. What a crazy idea.

 

The VA tax is supposed to replace the lost fuel tax revenue. As hybrid and electric vehicles continue to proliferate, this type of thing is going to become more and more popular. AFV owners are seen as "cheating" the taxman.

 

Now I think of it, it is bad programing, isn't it? It is understandable that the engineers wanted to cut out re-gen braking to protect the MGs from over-revving when there is slipping. However the ECUs could have been and indeed should be programed such that the same brake pedal pressure always gives the same total braking force, no matter the source (re-gen or frictional or both). It was programmed correctly under normal braking condition when re-gen switches to frictional braking at low speeds. It was obviously programmed not very well for the slipping condition.

 

It's interesting that some people are extremely disconcerted by this "feature", while others are fairly ho hum.

I know that I've experienced this issue from time to time, but it's never been a real big deal for me. The first time it happened was a bit unsettling, but I kind of got to used it. Some people however have literally gone out and sold or traded their Prius the very next day after it happened to them!

The circumstance under which I notice it most clearly is where you cross over ridge or discontinuity (like a rail line etc) that runs obliquely across the road (so that the front wheels contact it at different times,) and you're braking moderately, but still light enough to be fully regenerative.

 

Here are some old data:

Data on "brake loss" (aka "sudden acceleration&quot after bump | PriusChat

I will post some better analysis of more recent data later.

 

I don't think my car ever got that brake patch. Was that a TSB available? Just software?

 

I think the patch that Bob mentioned was for gen 3, not our gen 2 Prius (though there should be one IMHO).

 

Oh ok thanks 2009.