Adaptive Cruise

No, I misremembered. The manual shows it's actually the outline of the back end of a car at both the bottom of the graphic and the top (if a car is in range). I don't remember seeing anything when I braked. Kind of hard to keep track of and take notes on all this in heavy traffic.

 

Hey guys, see this post I have just made on my site:
Pre-Crash system - Prius-PT

You can see the BREAK warning message and the general working principles of the ACC system.

 

Sorry TP, but is there a question from you here? I really did not understand you, if commenting or asking... sorry mate.

 

OK, then I don't know the answer to your question. I was guided by the video I posted and the manual ggood copied here. I know nothing more.

It should be fairly easy to test this though. Just go to a highway, set the cruise speed to 80 or 90, and change lane to behind someone going slower.

You don't have to do it too risky, and you should always have your foot on the brake pedal just in case. Just make the Prius brake for you and see if the MID will show BRAKE! or not.

There are numerous videos showing the ACC on YouTube, it is really quite easy to demonstrate and test it without putting yourself into danger.

 

Really it should be quite easy, no risk involved, you don't need to go to a lane where someone is going MUCH slower...

Have a look at this video, the guy shows its Audi A4 ACC quite relaxed:

 

Good question.

It must not depend on LKA, simply because you can have cars with ACC and no LKA. We on Europe and our friends in Japan don't have LKA, but we do have ACC.

 

Heeyyyy, we Europeans don't have LKA??? When did that happen?!

That's bad news for me, and I'm sure a lot of others. Do you have a source?

 

Since design phase. LKA is for North American market only.

Source? Easy: Toyota-Europe.

Have a look at the European specs, the LKA is absent. Take a look at all pics where the driving wheel appears... the LKA button is there but no LKA characters printed, it's a dead button.

Don't worry, we'll have a FAR BETTER car than our American friends in all other respects.
At a price of course...

 

I'm wondering why it doesn't simply do the FULL braking for you in the event it is required. It seems like all the hardware is there, just a software re-write would allow the car to come to a complete stop as shown in those Volvo commercials. I'm wondering if it has to do with litigious fearing Toyota. Regardless, it seems like a great option especially if you are traveling in moderate traffic on the highway.

 

The car will in fact slam the brakes as part of collision avoidance. The line between adaptive cruise and collision avoidance gets a little blurred here. I'm sure for liability purposes, the instructions are emphasizing the need for the driver to be and stay involved in the driving and braking process. Not a bad idea, IMHO!

If you are saying the car should be able to come to a complete stop and then gradually resume set speed again, without me touching the brakes or the accelerator, that may be pushing things beyond the limit, both technically and legally. Seems to me there would be too many variables to account for, if they allowed cruise to continue to work past the current speed cutoff.

 

No, it will not, unless I terribly mistaken, it will not.

The ACC will beep at you when you get below minimum CC speed and the car is yours to control from that point on.

What the PCS does is to pre-load the brakes, and apply full brake assistance when you press the brake pedal, that's all as far as it goes in regards to braking. It will NOT stop the car for you, please BE CAREFUL!

There are only a couple of ACC out there that actually stop the vehicle if necessary. The system in the Prius is NOT one of them. It will disengage when bellow minimum ACC speed.

What will happen if you try it (I would nor recommend you!) is this:

 

We'll have to test that one out! The LKA will not work in significant curves (at least according to the book!). I've tried it in moderate curves, and it holds on just fine. If the LKA is working, then you will stay in your lane until you are close enough for the radar to determine you've reached your "too close" limit. If the curve is so severe that a car in an adjacent (inside) lane interferes with the view of the LKA camera, the LKA will become inactive. I don't know that it "informs" the ACC of this information, but I expect the car would back down in speed to avoid getting "too close" to the car that may or may not be in the same lane.

As I said, there is only one way to find out the real answer. Perhaps I'll know by next week. I expect to get another couple hundred miles of ACC use in by then.

 

Guess I'll have to read the collision avoidance section of the manual again. I thought it said it would apply the brakes full on at some point. By the time it decides to do that, a collision is probably already imminent, so it would probably only really work at low speed. I didn't mean to say it would actually slow and stop the car in time to completely avoid a collision. I was trying to imply just the opposite. Sometimes the magic works, and sometimes it doesn't! (movie reference - Little Big Man).

 

Does the radar interfere with radar detectors?