My questions are related to the LKAS features in my TLX Advance. The steering warning and steering assist seems to be working fine when I attempt to cross lines, but this is true whether or not I have pushed the steering wheel button which displays the two sets of dashed lines on the small display located between my tachometer and odometer. In other words, my LKAS seems to work whether or not I've turned it on from the steering wheel button (located at 5 o'clock on the steering wheel). My default arrangement, whenever I start the car shows the green ACC and LKAS symbols, but I must manually click on the dashed parallel lines every time I start the car. I have read through the manuals but am still confused. If someone understands my confusing attempt to explain my confusion, I welcome your comments. Thank you!

 

There are a lot of features to learn and explore. The shaking and warning that you are getting is from the Lane Departure Warning (LDW/RDM) and is controlled by a switch just above the trunk and gas filler buttons.

LKAS when activated on the steering wheel will try to keep the car within the lane markings by gently controlling the steering wheel. It will do this for up to 15 seconds after which a message is displayed in the MIDI requesting driver steering wheel input.

 

Quandry,

Thanks for your reply; it was helpful, but I am still a bit confused.

Whether or not the LKAS is activated on the steering wheel my TLX appears to perform steering correction when my car approaches white lines either on the left or right side. Perhaps you are stating that steering wheel "shake" only happens (without correction), unless LKAS is clicked-on and then steering correction takes place. Perhaps I am wrong and steering correction is not taking place whether or not LKAS is on. I guess I will have to play with it more to help me understand the differences between LKAS and RDW. If LKAS is only On when I click the steering wheel button, then I wonder why the green LKAS (and ACC) indicator is "lit" in the display every time I start the car?

 

Isn't the button "lit" when the cruise control button on the steering wheel is depressed? I've always viewed this as "arming" the system but not actually setting it.

 

If LKAS is not activated, the steering wheel will shake and provide resistance to cross the line, but only if you did not use the turn signal and if LDW is on. With LKAS activated you can actually remove your hand from the steering wheel (not recommended) and the car will follow the road even if there is a curve. With you hands on the wheel you should even feel it trying to correct the steering so that you are in the middle of the lane. Some people do not like this feel.

Anything other than the above is a problem, but I doubt that you have a problem, just going through a learning process.

 

Correct. The shake is the lane departure warning. The wheel vibrates a bit, and slightly resists you changing lanes or going over the line unless you have a turn signal on. The LKAS only activates when you turn it on via the steering wheel, and see the lane in the dash board. This will actually steer the car around a bend, etc.

 

Thank you for the outstanding explanation!

 

What's the difference, when you turn on LKAS between lane hash marks, sometimes they're hollow and sometimes the hashes are solid.


Anyone else ever feel like LKAS makes the steering feel more unstable...like its fighting you a bit?

 

LKAS steering only works when the hashes are solid, indicating that it has a good view of the lane markings. Normally I wouldn't use LKAS if the road conditions causes it to switch switch back and forth between hollow and solid because there isn't a warning beep when it no longer can steer (default setting).

It may be caused by you not fully trusting it yet and instinctively trying to steer.

 

Using LKA I've gotten the "Steering Input Required" warning on the screen a couple times. Does anyone know if that is indicative of it losing sight of a line (display changing from solid to dashed lines) or is it because I've "failed to steer the vehicle" as the manual describes? I've seen a post about requiring input every 15 seconds, but can't find it in the manual. If it's making small corrections and staying in lane, steering input is not needed, but I understand the necessity of it making sure I'm awake and still in the front seat!

 

Bingo. Even if you just keep a finger on the wheel and let it do its thing, it still might require a little more input.

I've noticed that sometimes, the LKAS will still let things get a little too wobbly. Especially in curves!

 

Getting the definitions clear (p382 & p383 of the Handbook), the LKAS display on the MIDI has either a pair of dotted outer solid lines or dotted outer contour lines (no hashes or hollow).

LKAS does make the steering feel a bit lighter but not quite to the point of unstable. If the line markings are good and you feel that it is fighting you then you are not keep the car in the centre of the lane.
You can usually tell, by steering feel, when LKAS is trying to perform a correction and these corrections are minor. If LKAS has been suspended then no correction is being applied, and when it resumes the correction will not be a major jerk or turn of the wheel. I feel it is safe to leave it on.

See p113 of the Handbook, but it does not state the 15 second part (this is from experience). The warning appears when you have failed to steer the vehicle for 15 seconds.

I anticipate that this will be enhanced in the future to keep the system active but there will be a load warning after a longer time period (like the Brake flash warning) if ACC is active. If still no input then gradual braking of the vehicle with the hazard lights turned on. The system makes little sense right now if the driver has fallen asleep, as it is like saying "you have fallen asleep so we are not going to aid in keeping the car in the lane".

 

LKAS is not part of being an autonomous car. Maybe next year.
It takes some time to get used to it probably like it did when you didn't trust cruise control.

I really enjoy how LKAS can steer around corners on the highway for 15 seconds. I have gotten used to it help me drive. Although, sometimes I want to drive so I turn it off to have the fun.

 

Thanks, confirmed when I just took a drive downtown. I got "Steering Input Required" after virtually letting go for 15 seconds, but it appeared that when it lost a line and the display markers went from solid to hollow, no warning was given. Agreed it is a little wobbly in some sweeping curves. Thanks to everyone... taking a longer trip tomorrow and will see if it seems to reduce driver fatigue, or simply keeps me alert watching it work....