lane keep assist (LKA)

Did you make sure that the lines were solid, meaning that the LKA is in effect? If the lines are not solid, it won't keep the car within the lane.

Also, you have operate the steering wheel in order for LKA to work. It gets canceled during no-handed driving.

 

For the LKA to be fully operational the radar cruise control (DRCC) must be set and you must be going over 50 MPH. It can operate as a lane departure warning system down to 45 MPH with the cruise control off.

It doesn't steer the car for you. It give the steering wheel a little nudge, and if you go far enough beeps, to help you back toward the lane center.

Mine works pretty well and it is probably a good safety feature but the real star of the ATP package is the DRCC.

 

Ahh, that explains why LKA isn't offered in Australia. Broken lines are standard here in Oz, solid lines indicate that it is illegal to change lanes.

Cheers
Warwick

 

Mine works perfectly fine with broken lines. I use it often on the New Jersey Parkway and New Jersey Turnpike, both of which have broken lane lines and LKA works very well on those roadways.

Rumple

 

No, no, no. Solid (bold) lines on the SCREEN, as opposed to thin lines. lol.

 

It also works better during the day, with plenty of light, and lane marker lines that have a high contrast ( as opposed to lane markers that are tough to see visually), the LKA system uses a camera mounted at the top of the headliner, behind the mirror and must have a clear view of the road to work.

 

Be sure to read the FULL PAGE of caveats about when LKA is
unlikely to function. It's a primitive vision system, and you
should think carefully before having something like that begin
substituting for you paying attention.
.
_H*

 

The Lane Keep Assist feature is a 'Gadget'. It is kinda like a video game for driving. It works when the Cruise is working or not, and it works when it can discern the lane markings. It does its job too well in my opinion. I tire easily of using it. It requires that the driver keep the car very precisely in the center of the lane of travel and "BEEPS" whenever you vary at all from that center position toward one side of the lane or the other. If it had more 'play' in its positioning, It would be more useful. I pay attention to my driving, but not that much attention. So I end up turning it off because the beeping makes me crazy after awhile.

Now the Dynamic Cruise Control, that's amazing, and worth having.

 

solid lines aren't required. It works with broken lines, but it helps to drive in a state that has money to maintain its roads. The roads in California are so dismal that sometimes the camera can't pick up the lines.

 

This statement is only partially correct. The DRCC IS a feature that is generally accepted as one dynamite feature, and worth the price of the entire AT package.

On the other hand, the statement that the LKA works while the DRCC is on or not is only partially true.

When the DRCC is activated, and the LKA is in operation, the car uses the built in camera in the rear view mirror to identify the lane markings and keep the car centered between those markings. In the LKA mode, the car will quite literally steer itself, even around gentle curves, and do a pretty fair job of keeping the car very centered between those lines. Again, the car will literally steer itself, as long as you are placing light pressure on the steering wheel and have not let go completely for more than 15-20 seconds, at which point it will cancel itself, and if you should allow the car to stray too close to either of the lane markings, it will alert you with audible warnings and nudge the steering wheel in the appropriate direction.

Without the DRCC activated, and the LKA pressed on the steering wheel, it defaults to LDW (as previously indicated by TumbleWeed). LDW does exactly what the ackronym stands for, Lane Departure Warning! It does NOT steer the Prius, it simply gives you tactile and audible warnings when you begin to wander from your assigned lane. Once again, there is NO steering input on behalf of the Prius, it lets you do ALL the driving and it does ALL the warning!

As also stated by new_Yorker, the camera does have to be able to see the lane markings, however, there is no consensus on how well defined those markings must be.

David (aka Blind Guy)

 

I travel about 42 miles to and from work. The road I take is very lightly traveled. Its hard to stay awake. I think this would be a great safety feature for me. The roads are flat and straight and the lane marking are almost new.

Maybe I should take one out for a spin and try it.

 

Extremely bad idea. It's not a substitute for paying attention. Load up on that coffee.

 

I ment the beep if I go out of the lane. Not to auto pilot me home......although that would be nice.

 

LKA doesn't work all the time (even if the lanes are clearly marked, due to several factors including too much glare from the sun) so if you become too dependent on the beeping due to sleepiness you run the risk of slipping out of the lane unaware. Still a bad idea.

My favorite case is that one story of an old couple who activated the cruise control in their motorhome and they both went in the back to prepare themselves some sandwiches. Off they went.

 

I would rather the car beep to alert me that I'm veering out of my lane than simply loading up on caffeine (and I loves me some caffeine). I think most people who use this feature do so because it is a great driving AID...not because it's a replacement for paying attention and driving the car. It's not "auto pilot".

I use LKA quite a bit on long road trips, and find that I'm far less fatigued at the end of the trip because of LKA and DRCC. I will say that the beeping can get a little annoying if you are in a lane that is not very wide.

 

It can also be annoying because often, it loses sight of the lane (giving an advisory "double beep" rather than the alert beeping), from things like: a shadow on the road (like from an overpass), a new lane starting, an exit or entrance ramp, worn paint lines, a car changing lanes close in front of you, glare from the sun, headlights not extending far enough out at night (like when there's a sharp uptick in the road in front of you), certain types of lane markers (like if there are only Botts' Dots and no paint), etc. etc. etc.

On the other hand, if you spend your 42 miles super-alert because you're playing the game of guessing when it's going to lose sight of the lanes next, well, I guess it's doing the job.

 

Excellent point.