Is Lane Keep Assist ready for prime time and worth the upgrade?

LKA and Steering assist IMHO only asset is the alarm that goes off when you get into the line without a signal.

Haven't had my gen 4 long enough to say anything about steering assist.

I used LKA for 4 years on my gen three in all of my 1300 - 1500 mile trips from Ma to FL or AR and back.
On these 24 hour (one way) trips it's good to have something letting you know that fatigue is setting in, time to pull over.
Of course you should notice fatigue before hand, having an alarm is extra.

The assist part has never done anything for me.

 

I would agree that it is probably good for fatigue or if you just generally have a habit of not paying attention (I hope not).

 

The lane lane departure alert with steering assist works really well for me. On the most sensitive setting, the beeping is too much for me. I kept on the second setting and it still works great. It does read little patches of paved road or imperfections of the road sometimes as a lane marker, so it beeps at those times.

It's a great thing to have when you always drive at night.

As for emergency braking, the car stops at any speed (I think) to avoid or lessen the crash. Under 18 miles mph, it stops for everything including people.

The emergency braking occurs when I'm in my garage because I have things like bikes and stuff in front of my car. Sometimes I get to close and it stops me. It is jarring, but it saves you from a new scratch on your new car. Overall from my experience, the emergency braking works great, too.

Parking assist it really cool and works most of the time. You still have to watch out though. Sometimes, if the parking spot is way to small, it still thinks it can park in it. So just look for a parking space you can fit in.

 

Good to learn more about this.

For me the bottom line is that I have zero confidence this will nudge me back into my lane. Just playing around with it -- sometimes it works and sometimes it doesn't. And that assuming the lines are well marked on the road.

Since it will beep at you if you change lanes without using your turn signal, it would be a good feature to inspire safer driving. That is about it, IMHO.

 

But if park assist requires me to decide if the spot is big enough it is essentially useless. Park assist should be able to assess and assist in parking in spots I consider small.
What happens if the spot is really small? It starts parking in and then what happens?
If the IPA is intended to help only on huge/ regular parking spaces then not much of a value add to me...

 

IRC, the sensors will let you know if you have enough space to proceed automatically.

My issue is a matter of confidence-- trust, really.

The car wheel will be turned automatically but as you give it the gas to move into your spot, the proximity sensors will be chirping wildly if you are close to the cars around you -- suggesting you back off.

Rather than be decisive and power into my spot, I chicken out.

Perhaps I need to practice some.

 

Maybe one should simulate it with big boxes simulating cars or friends' cars with somebody watching from the outside and giving feedback on how much space really is there.
My sensors on the 3 for examples are quite conservative, and will beep constantly when there is at least another good 20cm of space.
The sales person told me the IPA is a capable to park in spots leaving no more than 50cm in total front and back of the car. Which means 25cm and should be about the same as the sensors I have today.
There are surely geometrical constraints to how close you can park a car in a spot.

 

If the parking spot is really small, it will try to park in it.

You should be the judge on if your car can fit in a parking space. IPA is only trying to help you, not get into the smallest of spaces

 

Just got a 2016 Prius Four two weeks ago with all the accessory packages. LDA seems to work very well, I'm pleased with its ability to see the lines even when the visibility or condition of the paint on the pavement is marginal. With the Four and the HUD, it's quite convenient for me to see it and react (or not if there's nothing to worry about).

To be honest, I've never actually felt the steering assist. I've crossed over plenty of lines and I have the steering assist enabled in the menus. Manual says that it might detect if the steering wheel is "not firmly gripped" and activate the assistance in that case. Also says that the assist will happen if the wheel hasn't moved in a while, I guess I could test that on a curving road if there's nobody around.

It sure doesn't seem like my Four would drive itself down the middle of the lane if I took my hands off the steering wheel on the freeway. Of course I haven't tried to do just that at freeway speeds... Have other, more courageous 2016 Prius owners tried to see just how far the car will steer for you at highway speeds?

 

The LDA on mine doesn't seem to react until I have crossed the line, it then beeps and gives a little light nudge on the wheel.
The Adaptive cruise control was a little scary at first. I pushed the lever up and held it to increase the set speed and it went wild, I had accidently set the speed very high, not knowing it went up in 5 mph steps. I tried again later in the journey after I realised what I had done before, this time just nudging it up or down to the speed limit as it changed. I nudged it down as I went into a 40 mph zone from a 50mph (two steps) and as traffic slowed to a stop at some lights, the car stopped, then when the lights changed and traffic moved on, the car just followed with no input from me, well impressed, no feet driving ;o)

 

In my 1012 prius it would go up / down by fives, but in the new 2016, only by ones. Must be a new US thing.

 

You can adjust the sensitivity on the LDA assist. Mine was off at first, I had to turn it on.

 

Thanks for that Zojja, I didn't realise it was adjustable, must have missed that one when I was scrolling through.
Some of the menus scroll further down than I thought, I couldn't find how to add the extra hour on to the clock for British summer time yesterday, even though I had set the clock once 2 days before, it was further down the menu, Doh !

 

automatic braking and adaptive cruise control are far better reasons to get upgraded system... AEB is very good in new Prius, far, far, far better than the previous system and one of the top systems available.

It is actually able to do a full stop from at least 70kmh as tested in RX for EuroNCAP... it also works at all speeds, so it will always help out no matter what is the speed.

It is very, very good system... previous system was just barely better than warning.

 

From JNCAP:

They aced all JNCAP tests in new Prius... actually page is informative for everyone, test goes up to 50kmh for stationary and 60kmh for moving target, plus it shows other cars - ones with simpler yet still excellent TSS C, Prius with TSS P and then older models which had very expensive system that could barely stop at any speed -
JNCAP｜予防安全性能アセスメント -

You can check other manufacturers as well. For example before this year, Lexus systems were far worse than TSS C or P and we $2k in cost... except in LS, that had a good one since 2014. Honda is fine only in system introduced few months ago, Subaru's EyeSight has been good for 2 years, Mazda's is still not up to par.
JNCAP｜予防安全性能アセスメント

 

It is good enough that I'm waiting a year for a Level 2 ECO with the announced, automatic braking. So a salesman from the local Toyota dealer called and said he could get a Level 3 with ATP for the same price as a Level 2 ECO. I thanked him but said I'll wait.

Bob Wilson