Forgot to shift out of B-mode before entering Freeway

I drove for a good 2-3mi at 60-65mph before noticing i was still in B-mode.

Did I screw up my Engine?

To the best of my knowledge, it should only waste a bit of energy from your glides. If you didn't have any glide or coast opportunities, it should have done absolutely nothing.

No, of course not. Don't worry. You only hindered your MPG at the moment, nothing more .

EDIT: Patsparks is right, I didn't notice you were going 60mph or more. So absolutely no harm at all .

No harm done. I even doubt you affected your fuel consumption very much if at all. At 60 to 65 miles per hour you don't take your foot off the accelerator much at all.

Inept dealer story
After having driven the prius for two days I started using the b mode but had no Idea how to turn it off-get out of it, used it twice and both times I wasn't about to start moving that lever around while moving, thinking about a regular car;s transmission locking into reverse at speed and the resultant deceleration, err tyre squealing stop... so I would stop and turn off the car anr restart, well twice anyway, called the dealer, got the salesman, and the mf, laughed at me, I'll go see him again for my next car, not

This is a good article on B mode:
http://www.techno-fandom.org/~hobbit/cars/b-mode.html
With this quote: The difference betwen "D" and "B" only appears during decelerative coasting [no pedals pressed at all] or actual braking. When accelerating or just maintaining speed, "D" and "B" produce the same behavior.

I so disagree
in the owners Manuel it says don't spend more thime than you have to in b mode or you will over heat the part that is b moding

when I use b mode I immediatly start to slow down, from friction, and I hear a noise that get's louded the longer I'm in b mode
not flaming you, just not letting misinformation get thru

No, this is not how B mode works. B mode does not increase friction braking, but uses the ICE as an air pump to throw away excess energy.

Tom

I use it about once or twice a year. I needed it to go down this small hill last weekend:

You need a parachute for that hill.

Tom

It has a 1 1/2 lane paved road that is at least a 7% grade and if you missed a turn, you wouldn't stop until you reached the American River.

To the OP I woud simply say:

No, I don't think you screwed up your engine. However, as you already know this is operational behavior you want to avoid.

There have been numerous threads on "B" mode. Which kind of tells me Toyota needs to clarify how it should be used, and what it is actually doing. Too many people just don't seem to really understand it's operation and intended use.

I watched a Youtube video review, that was posted here, where a Toyota "expert" refered to "B" mode as "Battery".

When you buy the automobile you'll be lucky if the salesman really knows what "B" mode is all about.

Toyota has so many great instructional videos on so many aspects of The Prius, a clear, definitive short instructional on what "B" mode is all about would certainly be helpful to a lot of people.

My understanding born mostly out of reading threads here at Prius Chat, is that it's intended use is much like a Jake Brake on a truck. That is for coming down off a large incline. I think it maximizes regenerative brakeing and slows momentum. Exactly how it is doing that is somewhat a mystery even to me at this point. I've heard it's using the engine, it's NOT using the engine, it uses the brakes, it "changes" the brake input...

As best I can tell reading the posted information it's mostly a Jake Brake like operation, using the engine to slow the vehicle.

It becomes confusing only because it's a unique mode for an automobile and it's a mode intended to be used for a very specific situation.

I live in Oregon, so it's not impossible that I could be in a driving situation that would benefit from use of "B" mode. Lot's of hills and mountains. But for city driving and majority of "regular" driving I don't think I'd even touch "B" mode.

Its basic intent is to produce the braking from engine compression that a pre-hybrid gets when downshifting on a downhill grade. That part is not at all unique.

But because this is a hybrid, with new tricks in the toolbag, it also does more, and changes modes depending on circumstances. So, yes, these parts are unique.

I like what you say, the timesI find myself on the highway in b mode. having forgotten to shift out of it, have been moments of, damn, did it again, and the way I find I'm in b mode is to put it in cruise control, which won't work in b mode, luckily, or it would be miles or hours before discovery

Greetings All,

I'm a new Prius owner and I use the "B" mode on a regular basis. However, I shift into and out of "B" mode while driving. So far, no ill effects, but I'm learning more about it.

Cheers - OS

Care to explain why you do this? There aren't many situations where this would be advantageous.

Tom

I am amazed at the quantity of posts about B mode that do NOT understand what is going on.

When you slow down by coasting or light braking, regenerative braking charges the battery. On a long downhill, your battery will reach maximum capacity and when the computer won't allow more electricity in, you will have to use your mechanical brakes more.

B mode is for the Prius what a Jake brake is for a semi ... it turns your ICE into an air compressor. Driving the ICE as a compressor puts a lot of drag on the car ... slowing it down.

The noise you hear is nothing more than the ICE spinning up to about 4000 rpm ... with no fuel or spark ... and heavily slowing down the car. You can accelerate and/or control your downhill speed with the throttle just as you would in D. BUT, where you might use your brakes a lot in D, you might not use your brakes at all in B mode.

And, what is this thing about overheating something? Doesn't happen.

I am currently on a vacation trip through the Rockies. B mode will easily slow the car from 80 on a 6% or 7% grade ... without touching the mechanical brakes.