Breaking-in mode "B" Question

100% agree. B mode will do no harm at all during break in. But to use it on a flat grade going through a town is not going to help enough for the inconvenience of having to keep switching back and forth.

 

B-mode should not be used "regularly". It is beneficial when going down steep or long hills, as it uses the ICE to slow down the vehicle. On long hills, it also reduces the need to ride the brakes.

In normal "light" breaking, the friction brakes usually do not even come into play. Instead, the electric motors provide braking, and also help to recharge the traction battery ("regenerative braking"). Because of much of the braking being regenerative, it is common for most Priuses to not need their first brake job until well over 100,000 miles (and sometimes much longer than that)!

The friction brakes activate only in moderate to heavy breaking pressure, or for "panic" breaking (when you hit the brake quickly), or for when ABS or VSC are called for (I think).

Best wishes,

 

Correct on VSC. The ABS sensors, yaw sensor, and gyroscope all tell which brake to engage to correct the vehicles path.

 

Thank you very much for the confirmation on that, Jabber. I thought as much but wasn't 100% certain.

 

Who told you to use "B" all the time, some salesanimal? Bad salesanimal, bad!

The one thing that "B" *does* harm is fuel efficiency. It forces use of engine braking, wasting some energy that could otherwise be used for gliding, coasting and capture by the battery.

 

noobie question: is there a difference between coasting and braking?

If I am going 55 and i see my destination 1/4 mile ahead, and there is nobody behind me, is there a difference between lifting off the gas and coasting with no input to the destination except braking at the end to stop or gentle gas to make it there and using shifting to neutral or braking lightly?

Similar question - which regens more - lift off gas and coast or light braking?

i changed my original front brakes at 140K miles and i am a coaster, but want to know if I am missing something

thanks in advance

 

The display does not provide numbers so it's hard to assess how much regeneration you're getting; but generally:

Gliding = no arrows on the "Energy" display: no regeneration
Coasting = arrows into the battery on the "Energy" display: some regeneration
Light braking: more regeneration
Heavy braking: regeneration plus friction brakes
Neutral: *no* regeneration no matter what else you do. Don't use it except at an automatic pull-through car wash. It's better to learn how to push the gas pedal just enough to make the arrows on the display disappear.

In the 1/4-mile-to-stop scenario it would use minimum energy to coast the entire distance and come to a stop just at the sign. Of course that ideal is impossible to judge and do in practice; the challenge is to approximate it as best you can without going insane or inducing road rage in the drivers around you :_>

 

Oh, you will :_> Watch the display. Pretend that you have no brakes. Check tire pressures at least monthly. If you don't mind a harsher ride, inflate the tires more, up to the maximum given on the side of the tire. Don't use "B" unless you're coming down the Blue Ridge Parkway.

 

ok - this is a change for me - i coast and then brake hard, but now i understand that if i need more regen i need to feather the brakes to grab more regen

this may be a gen 1 issue, but the coasting where you are pressing the gas juuuuust right to get no arrows - almost impossible in my 2002 to achieve. is it easier in gen 2?

 

Did you trying letting go and then pressing back down slightly?

 

yes - i diddle all around it, like a clumsy schoolboy in the dark on his first date

 

You were told wrong ...... WAY wrong.

... Brad

 

Well maybe 2002 is more difficult to handle than 2009.

 

i do ok - 80% hiway and i get a respectable 50 mpgs in the summer

 

Uhh, ya got me: maybe so. I've only driven my '04, and in it gliding is not hard.

 

i really focused on this last night on my 35 mile commute one way.

i achieved it a total of 3 times. I would get to speed, then back off slowly and i would go from propulsion to regen in a blink. Then i tried getting to speed and backing all the way off into regen and applying increasing pressure to find the sweet spot.

it is a challenge on my commute because it is HOV, about 65 mphs, usually quite crowded, and actually a little hilly. The differential speeds between the hov lane and the next lane get pretty high and dangerous. If the next lane is oding 20 MPH i don't want to be doing 65 - not enough time to slow if some idjit pulls out, so i frequently have someone on my nice person as i try to pulse and glide.

 

Maybe I missed something earlier. "No arrow" state usually only happens below about 40 MPH. I only see it very occasionally at highway speed.