Brakes Unexpectedly When Large Truck In Next Lane

[SirChargesAaalot]

Hi everyone!

I finally got the A3 down to southern California and back up north. So my first long distance drive with it. I must say that it fared quite well and was a pleasant drive. I enjoyed it quite a bit, minus one behavior I felt wasn't well tuned.

I5 is a super long straight line 2 lane (in each direction) highway with lots of large trucks driving up and down CA on it. It's very common that you'll be in the left lane passing large trucks driving in the right lane. Once I came up to the rear end of the truck, even though it's in the lane right of me, the car was hitting the brakes very abruptly and messing with people driving behind me, of course they were all tailing all the time, but that's for a different discussion.

I noticed that by driving slightly more to the left side of the left lane, I was able to avoid this behavior all together and I'll be the first to admit that I likely drive slightly shifted to the right to begin with. But I have other cars with safety braking features and they have never done this to me before. Do any of you run into this issue at all? I experience it pretty much every time a large truck is creeping in on the lane, but it feels too aggressive. I'm curious if there is something wrong with mine specifically or if this is par for the course with the way they tuned this system.

Thanks!

 

[Jacks A3 ET]

I assume you have the "Lane Assist" feature. I have a 2017 Golf Alltrack with the Adaptive Cruise and Lane Assist It all works well on long road trips. But on occasion if I am in Left lane passing a large truck on my right and the road turns slightly to the left, that same brief auto braking occurs. I my experience, these Radar / Camera sensing systems can be sensitive to reflections of White trucks, And if these sensor are dirty may be not work well?
Also learned that if there was any slight damage to the Bumpers - these systems may need recalibration.

 

[SirChargesAaalot]

I assume you have the "Lane Assist" feature. I have a 2017 Golf Alltrack with the Adaptive Cruise and Lane Assist It all works well on long road trips. But on occasion if I am in Left lane passing a large truck on my right and the road turns slightly to the left, that same brief auto braking occurs. I my experience, these Radar / Camera sensing systems can be sensitive to reflections of White trucks, And if these sensor are dirty may be not work well?
Also learned that if there was any slight damage to the Bumpers - these systems may need recalibration.

Thanks for your reply @Jacks A3 ET ! I'm unsure if the braking is tied directly to Lane Assist or rather Audi "Sense". I believe the only thing Lane Assist does, is correct the steering wheel and vibrate it. The braking is more of a collision avoidance feature, my best guess anyways.

When the opportunity arises again, I'll try turning the features mentioned above off/on to figure out at least which feature this braking is tied to, then keep going from there.

I feel you may have a point with calibration being a factor, I'll do some research and see if that's theme anywhere else. I do not however think that this vehicle has been in any collisions before, the body looks all original paint to me and carfax was clean...

 

[Jacks A3 ET]

The Phantom Braking I have experienced is from the Adaptive Cruise control. It "sees" the Truck as a vehicle moving into my lane and wants to slow speed and back off the distance between the truck and my car. Same thing will happen if some jerk cuts in to that space the Adaptive Cruise has set as a safe distance.