RHD TJA seems to prefer going left

[ReintjeWA]

Hi all,

The other day I noticed that whenever I’m driving with ACC and TJA active, which I really only use on the freeway, the car seems to always try and follow the off ramps. Whenever I pass one the steering wheel clicks as it tries to gently veer left and I hold it centred.
It feels like the car anticipating where we are going, but getting it completely wrong every time. No other cars in front to follow either.

It was a long drive and got me wondering if perhaps the software has a bias for the left side of a fork as this would normally be the main route someone is following? This could make a little bit of sense when driving on the right (wrong) side of the road, as then the left fork would be the continuation of the freeway.

Does anybody else that drives on the left experience this? Or do those driving on the right experience the same?

 

[Ian Key]

I'm slightly confused. Do you have ACC active or TJA active?

 

[ReintjeWA]

TJA, so it’s steering to stay in the middle of the lane. I mentioned TJA specifically because I suspect that’s what’s trying to stay in the wrong lane.

I find TJA a bit of a misnomer because it sort of implies it only works in a traffic jam, but it is also a steering aide at higher speeds. And this behaviour happens at the higher speeds.

 

[fnegroni]

I don’t remember it being any different when I drove my RHD mg4 (2023 reg phase 1) in France: as in I think it pulled to the right when there was an exit on the right.
But this has changed more recently and as I mentioned in a much earlier report, after the first upgrade of the camera module TJA needed a good amount of road to retrain itself and I now leave it permanently in standby and has improved slightly over time. Might be just placebo and it’s nowhere near as good as other systems, but it’s better than it was this time last year when I had the upgrade.
Drove my sons my2025 Kia and it was bliss.

 

[Ian Key]

Perhaps the lane markings were worn from traffic exiting at that off ramp and the system failed to pick them up.

 

[ReintjeWA]

Perhaps the lane markings were worn from traffic exiting at that off ramp and the system failed to pick them up.

It’s consistently doing it on all off ramps along that road. The whole project was completed in 2020, so most of it looks all right to my eyes (although I’m also pretty sure main roads hasn’t done any significant maintenance since).

 

[DixieTGS]

Is it the case that on your left, the the continuous line on the freeway continues on to the off ramp and the style of line between the freeway and off ramp is different to any line the car has been tracking recently? If so maybe it only 'sees' the continuous line on the left and dotted on the right diverging, and chooses one or the other to follow.

I've had similar things happen going from one to two lanes. I've tried to follow the left line but LKA (not TJA) has tried to put me on the right hand of the 2 lanes. It's happy again soon after the new dashed lane divider appears.

 

[siteguru]

What if you're driving more towards the right rather than middle or left side of the lane?

I have a recollection of this topic being discussed a couple of years ago.