is TACC speed dynamic?

[alexander3192]

Hey guys,

I am a new owner and I have a question regarding TACC to which I could not find a manual explanation. I will explain a case for easier understanding.

I am driving on freeway with 110km/h and activate TACC. I drive on the first lane and aproaching a truck that drives with 90kmh. As aproaching the truck the car slows down(probably to keep distance).

If I move to the left lane way before, the car maintans the set speed, but then it means that it takes forever to overtake the truck and keep the second lane blocked with my 110kmh.

Is this intended behaviour or is the phantom braking?

With my old ice car I set the cruise control to 110kmh and I only move to the left lane when I get close to the truck. The car never slows down on itself.

Is that not possible in Tesla cars?

 

[Stew-2]

What you are describing is normal TACC behavior. That is not phantom braking, phantom braking really hits the brakes, I personally haven’t had that happen for a while - it’s gotten much better.

Unfortunately there is no standard dumb cruise control, only TACC.

 

[alexander3192]

What you are describing is normal TACC behavior. That is not phantom braking, phantom braking really hits the brakes, I personally haven’t had that happen for a while - it’s gotten much better.

Unfortunately there is no standard dumb cruise control, only TACC.

I see, so there is actually no way to prevent the car slowing down such long distance before a slower moving target?
It kinda sucks because the alternative would be to either constantly increase/decrease speed (which kinda cancels the cruise control benefits) or move to the 2nd lane and spent 3 minutes trying to overtake a truck pissing everyone off.

 

[Stew-2]

The only two controls you can adjust are speed and following distance with the right scroll wheel.

In situations like that I’ll usually disengage, overtake vehicle, reengage. Also frustrating is I’ll set it merging onto a freeway and it’ll slow back down at times because I’m still on the on-ramp and it knows better than me.

I wish it had a dumb mode.

 

[fhteagle]

There is a very definite bug in TACC where it maintains a following distance behind a car / truck in a neighboring lane. I've seen it since new delivery a year ago when a car was in my lane and was a valid following distance target and later changes lanes, and the TACC never resumes the "max" set speed even when the lane in front is completely clear. If the previous following target moves into an exit lane and is aggressively slowing, guess what, you are too, which is not at all what drivers behind you expect, and is rather dangerous.

It's like the logic to say "stop following that car" was never programmed in the first place.

Sometime around August 2023, I have also seen this bug in the form of TACC actively slows to maintain following distance of a vehicle that was never in my lane in the first place.

Again, it's not "phantom braking", but it's a very definite "failure to accelerate".

 

[The Other Dan]

I see, so there is actually no way to prevent the car slowing down such long distance before a slower moving target?
It kinda sucks because the alternative would be to either constantly increase/decrease speed (which kinda cancels the cruise control benefits) or move to the 2nd lane and spent 3 minutes trying to overtake a truck pissing everyone off.

Ok, I'm gonna blow your mind with this one...... hold on..... here is comes....
You know you can actually move your foot an inch or two and actually push the pedal while using cruise control? Then when you've overtaken the vehicle, take your foot off the pedal and it will contine at whatever speed you previously set. I know, it's amazing. Unbelievable really. But even you can do it.

If you're pissing everyone off letting the car accellerate on it own to overtake a vehicle, that's 100% on you. Not the car.

 

[Stew-2]

That also works with phantom braking. There are a lot of settings and tricks to discover, especially for the new owners, and I forgot about this working in the OP’s situation. Not sure what that weird tone of your post is about.

 

[jjrandorin]

Ok, I'm gonna blow your mind with this one...... hold on..... here is comes....
You know you can actually move your foot an inch or two and actually push the pedal while using cruise control? Then when you've overtaken the vehicle, take your foot off the pedal and it will contine at whatever speed you previously set. I know, it's amazing. Unbelievable really. But even you can do it.

If you're pissing everyone off letting the car accellerate on it own to overtake a vehicle, that's 100% on you. Not the car.

The information here is good, but is delivered in such a condescending way I came very close multiple times to moving it to snippiness or deleting it.

I mention this because I am not sure what the intention was, but this reads pretty poorly even though " you can accelerate yourself " is valid feedback. I also mention it to try to head off the inevitable response from the OP about how poor this reads, which likely would start a back and forth I am not looking for here.

 

[nicksp]

OP, when changing lanes you could increase the speed manually and then the car will go back to its original set speed.

 

[alexander3192]

OP, when changing lanes you could increase the speed manually and then the car will go back to its original set speed.

Well, this I did not knew and it makes sense and it's a good thing. My old car would not go back to the set speed if I accelerate or decelerate from cruise control. It would just deactivate the CC and then I needed to re-activate it at desired speed.

So that is helpfull and it helps with the issue.

When you say "manually" it refers to both the scroll wheel and the accelerate pedal or only the scroll wheel?

Thanks for the info.

 

[nicksp]

Well, this I did not knew and it makes sense and it's a good thing. My old car would not go back to the set speed if I accelerate or decelerate from cruise control. It would just deactivate the CC and then I needed to re-activate it at desired speed.

So that is helpfull and it helps with the issue.

When you say "manually" it refers to both the scroll wheel and the accelerate pedal or only the scroll wheel?

Thanks for the info.

The pedal only. The scroll wheel will change your set speed.