Engine Braking at High Speed

Yes, you can use B, but unless the hill is very long, you are better off leaving the Prius in D. B mode deliberately wastes energy by spinning the ICE. This is fine if that's what you want to do, but normally it's better to put that energy to use by saving it in the traction battery. Use B only on those long mountain roads where you know the battery will be fully charged before getting to the bottom.

Tom

 

Someone will correct me if I say this wrong, but with Prius, riding the brakes is not such a bad thing as it is with conventional cars. I spent quite a while teaching my other family members not to ride the brakes because they overheat. I even was in the habit of looking down on others if I saw them riding the brakes down a hill.

But with a Prius, light brake pressure regenerates energy. Unless the hill is extremely steep and you are doing some fairly substantial braking, it doesn't seem like you will liekly overheat the brakes.

I wish there was a MFD display that tells you if the friction brakes are employed. I have not been able to feel them kick in as I drop below 7 MPH, but that is actually pretty slow.

 

Welcome to PriusChat, Marvin!

If you are traveling at highway speeds going down a hill and you fill the HV Battery (it goes solid green) you can really feel the friction brakes kick in as the car stops putting the regen charge into the battery. That is definitely a time for B mode. It's hard to feel the mechanical friction brakes at low speed, which is how it should be.

The Prius is smart and won't let you hurt it. You can put the shift switch into any gear you want, like bumping it into R at 60 MPH, and the car will ignore you. If you're cruising around town and press the Power button, the car ignores you, unless you press and hold it, signaling an emergency shutdown. Same thing is true of the Park switch; if you're moving, you're not parking, so the car ignores your press. And not to suggest being lazy or anything, but if you come to a stop with your foot on the brake and press the Power button, your smart Prius will put itself in Park and then shut down.

 

<div class='quotetop'>QUOTE(Marvinh @ Jul 12 2007, 02:29 PM) [snapback]477615[/snapback]</div>

You can notice when the engine braking kicks in (right away). The force you feel is not gradual but happens as soon as you are in B. It feels like you suddenly slam on the brake maybe 1/4 pedal distance to the floor. You will probably gradually slow down but I have not use it until it comes to a complete stop. I have only use it for maybe 3-4 seconds because I hate wasting energy.

If someone is behind you, be very careful using it. The driver behind will not see you brake (no brake light) and get off guard.

 

Your last comment here was a question I've had - When you shut her down, it's really not necessary to go "P" then "Power off" - one can just press "Power off," right?

 

Yes, I do it all the time.

 

That's what I said...

 

Hmm... What would happen if someone held down the power button (until it turned off) at 60mph or so? Would the parking paw engage?

 

so it goes into neutral and then turns off all power?

Lets see... what about at 108mph? Won't the ICE stop and then the MG's spontaneously self-destruct?

 

Driving into a bridge abutment is an effective way. It works with normal cars too.

Tom

 

I'm sure I've corrected you on this a few times now (but maybe it was someone else).

It goes into ACC mode and Neutral if you turn the power off while moving. And the ICE stops.

 

I thought holding down the power button for like 10 seconds would essentially do a "hard reset" similar to laptops, used in the event if the prius OS froze up or something?