You havent said a word about the condition of your wheels/tyres etc - they can impact the Sensing suite.

 

100% this, once our lease was up for our 2020 with under 10k miles(cause covid and we ended up having getting a hybrid and that became the work horse during lockdown), first thing i did was throw the factory ecopias away from some pirelli scorpion as. I used to always turn on lkas on the highway with the ecopias, because there was just so much sway and this was evident as when LKAS was on, it would constantly beep. After the pirellis, i stopped using lkas as the car just felt ALOT more stable, and when i do turn it on, it barely beeps anymore. also Tire threads might still be good height, but if you're still using factory, you're essentially using 5 year old tires

 

Over the last 5,000 miles, lane departure frequently actuates (steering wheel shimmy/Visual warning).
Driving over the same roads for 45,000 miles, never had the issue.

Turned mine off after the first two days of ownership. Most annoying, least useful, “drivers aid” ever.

 

Road Departure and seat position are two different problems involving to different processors.
Road Departure detection is performed by the front camera, seeing or thinking it sees you crossing a solid line. This may be a white/yellow line or something that looks like a solid line. Such as where they poured tar across the road to repair a crack can create a false trigger or old lines in the road left by construction work. So my first question is this a possibility? Also does LKAS seem to function correctly or does the car wander within a lane or drives to one side of the lane instead of holding near the center? Recalibration of the camera may help but ask the tech to note what the calibration looked like before any adjustments are made. If you tend to drive near the solid white line (like my wife does...she'll put the right wheels on the line) than a little camera misalignment will trigger a Road Departure. Of course it simply could an issue with the camera.

I turned off Road Departure years ago when driving up a new ramp to get to the interstate. Construction crews forgot to cover the old solid line where the new ramp and interstate intersected. Needless to say the driver's behind me were not happy campers.

The power seat positons are controlled by the Power Seat Control Unit, which may of had a stroke. Before considering replacing it you might consider performing a reset on the whole vehicle by disconnecting the negative cable from the battery for about minute and reconnect it. This sometimes correct these little glitches. Note that when you restart the vehicle you will get a plethora of warnings. This is normal anytime the car loses power, they will clear themselves when you drive for a mile allowing the car to run some diagnostics to make sure everything is ok.

Edit: Should clarify the seat positioning scheme, the BCM "body control module" sees who is entering the driver side door via which fob is next to the door. The BCM sends a signal to the power seat controller to position the seat to driver #1 or Driver #2. It's up to power seat controller to know what these positions are and to move the seat to the appropriate position.

 

The car never wanders.
Lane keep assist works, but I drive down the center of lanes without making use of it. I recall it only works for a limited time before asking you to drive once more. I’ve had it turned off for a long time, just using basic cruise control.

No alignment issues.

 

Whatever you do..

re balance all tyres and check for un even wear.
have a 4 wheel laser alignment

Consider a re calibration of it all, all those miles things do get rattled /shacked about.

 

How old are thes second set of tyres?

 

Installed November 2022.

Over the last 5k, the lane departure steering wheel jiggle and orange dash warning have become a daily occurrence.
Over the first 45k, including first 30k with the mediocre Ecopias, I never encountered Lane Departure.
Car just turned 50k, somewhat low mileage for a 2018.

 

Perhaps worthwhile getting all the wheels rebalanced.

 

Seems an easy start in Uk where I am £20 for all four and the guys comes to my home for that.

 

I turned off the road departure mitigation switch located in the lower left corner of the dashboard, which turns off the Lane Departure Warning Function.
Done deal.
No alignment issues. Tires are balanced and inflated to recommended pressure.

I double checked. The noisy OEM Ecopias were replaced at 23,350 with Pirelli Scorpion Verde which have a 60,000 mile expected life per Tire Rack. I'd be satisfied with 40,000 to 50,000 miles. These tires have excellent wet road performance.
A Tire Rack van fitted with a tire changing machine and spin balancer came to my house......very impressed.

 

I hate mine, also. Even when I have the turn signal on, it will stick jerk me back into the lane. I turn mine off, also.