Lane Keep Assist and Lane Centering
 

2016 RX 350
The Lane Keep Assist (LKA) works well; automatically turning the car back into the lane when starting to cross the lane lines.
However, when the Cruise Control is on and Lane Centering option is on the car does not maintain a good center. On a straight portion of a newly paved and marked interstate, with no wind, the car wavers side to side about half a lane width. Occasionally it will go as far as the lane line at which point the LKA kicks in. This is with no steering correction on my part.
If I steer to keep the car in the lane center the steering is heavy and I feel as though I am fighting what the car wants to do.
If I turn off the Lane Centering the steering is easy to keep in the center of the lane. The LKA is still on in this case.
I explained this problem to the Lexus dealer's expert and he was not aware of the Lane Centering option until I showed him the manual. He test drove it and concluded that that's the way it is until Lexus comes up with new software.
Does anybody else have this problem? The Lane Centering option is on by default only when in Cruise Control mode.

Mine is working the same as yours. I have found it will only try to stay centered when going straight and on a small curve. If the curve is too sharp it will go beyond the lines.
If you let go of the steering wheel you get the warning every 30 seconds to take hold of the wheel.
What happens if you do not take hold of the wheel? I have let mine go about 1 minute and it just keeps beeping.
I hope they can fix this in the software and it will be down loadable to existing cars.

For me, it is good on a straight line. However, after a few min it will hug a lane and compensate and oversteer. But it also tells you to keep your hands on the wheels so I just use a finger and lightly nudge it back.

This isn't a mercedes or tesla. Lexus is behind on these features so don't expect anything crazy!

When I used it for a trip to Hilton Head the LCA seemed to work OK with some ping ponging. The other day I used it again and the ping ponging was severe. I did notice the road I was on had a larger than normal crown. They do need a software upgrade to make this better. Other wise you do fight the wheel some when it is on

Yes, be aware of the rate of curvature of the road you're on. For me, it works great on one major highway here (loop 1) southbound, but northbound the road curves too much for it to stay in its lane. So under no circumstances can you let go of the wheel.

Lane centering not functioning
 

2016 RX 350. Had been using cruise control with LKA and lane centering without problems, until I had the navigation system reset due to a software problem that was announced via email. I have taken two long trips to south Florida driving on major interstate highways with clearly marked lanes, and noticed the car drifting towards the right, crossing lanes with the cruise control active. My husband also noticed this as well. We were both having to actively steer the car back in between the lanes. We have tested this on many roads, and within the center lanes to be sure it was sensing the lane markers. I took the car to the dealership, and they looked at me like I was crazy. They have never heard of this problem, and neither has Lexus customer service. They thought I was trying to drive the car hands-free! (yes, I know this is not a Tesla.) Hope anyone out there has any other information on this!!

Lane keep assist with centering is by default turned off. I wonder if the software update turned the setting back to default value?

Check the setting in the instrument cluster settings.

It does what it was designed to do and "assist" is about it.

GM calls this Lane Keep Assist and it automatically steers the car toward the middle if you wander out of the lane. I have it on a 2016 Denali and it works about the same as Lane Centering on the Lexus. The Lane Centering term Lexus uses is misleading. My expectation was that it would be an improvement over the Denali but it is the same system with the same limitations..

+1
The system is working as designed to be reactive in correcting the driver's input in the event the driver sways close to an adjacent lane. LKA works the same in the NX.

Thanks - I have gone through all of the LKA settings and made sure the lane centering is 'on', as well as adjusting the sensitivity, etc. I even tested this using cruise control on a city road, with max speed limit of 45 mph. For some reason, the car wants to drift off to the right, crossing the lane, then alert me that the car has crossed the lane, then try to overcorrect. While I'm steering, it feels like my sense of center is not the same as the car's sense of center, and I'm having to do more to keep the car within the lanes. Is there a way to reset the car software myself?

That is exactly what my RX is doing. Has any tech specialist at your dealership been able to help you with this? I put a call out to Lexus customer service, awaiting a callback.

Lane Keep Assist + Cruise Control in RX = ??
 

Hello,

I got a question I was wondering somebody could help me with... I have a 6 months old 2017 RX 450h and yesterday I had a chance to use cruise control for the first time (on a highway)... The moment I turned it on I felt steering wheel grew heavy and I needed to apply a bit of force to keep the vehicle in lane. I quickly realized that it is trying to steer the car with LKA. However, if I were to stop resisting it, it would steer the vehicle *out of lane* (!!!) and monitor would start buzzing the steering wheel indicating I'm out of the lane... HUD indicates LKA can "see" the pavement markings the whole time. If I turn off LKA with a button on the steering wheel, it stops trying to steer off the road and, obviously, stops the indication I'm out of lane if I truly am... I suspect this is not the behavior by design? If so, what do I do?? I could turn off steering assist in LKA settings, of course...

Thanks!

You need to do more experiment and find out if the LKA is actually calibrated to stay in the middle lane. And yes, if you have LKA on, the steering wheel will resist if you stay out of lane. And normally this is calibrated to stay on the inner left lane. And the LKA is not a constant pull or push but more of impulse to keep the car at the inner left lane. There is also a setting to keep the vehicle at the center lane. If it doesn't stay on inner left lane or the center lane you might want to check with Lexus to calibrate it.

do you have your lane centering turned on for the LKA? If not, it will pull you towards one line or the other.