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TACC and changing lanes

Discussion in 'Model S: Driving Dynamics' started by Hookemhorns, May 17, 2016.

  1. Hookemhorns

    Hookemhorns Member

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    Still waiting for delivery next month! Soaking up all I can.

    The manual says when TACC is engaged (but not auto steer), if I engage a turn signal, the car will speed up anticipating I'll be moving over to the next lane.

    What is this experience? What if I don't change lanes quickly, or just don't change lanes at all…how close will I pull up to the car in front of me now? I'm guessing the car accelerates preparing for me to move (I like that), so it will approach the car in front, and will slow back down if I just stay where I am. I was just hoping for some reassurance that this is what does happen.
     
  2. Racerx22b

    Racerx22b Member

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    The speeding up to overtake via use of the turn signal only works when autopilot (AP) is engaged. TACC does not change lanes when using turn signals. However, if you have cruise control set at 80mph and you come upon a car going 70mph the car will automatically slow down. When you steer out of the lane and TACC senses that no slower vehicle in front of you is present it will automatically resume to 80mph.

    When AP is engaged, it will do the same thing but you don't have to manually steer to another lane. All you do is turn on the turn signal (when AP senses and available lane to your right or left) and the car will change lanes and speed back to your previously set speed. The lane change occurs slower than you would manually change lanes just in case you are wondering.

    Jason
     
  3. Hookemhorns

    Hookemhorns Member

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    As I understand the manual, AP (autopilot) refers to several components: TACC, auto steer, auto lane change, auto park, and auto high beam. So there is no such phrase as "AP is engaged." I think you meant "auto steer engaged." And I agree with your explanation.

    But, my question is if TACC is engaged but NOT auto steer. The manual states:

    "Overtake Acceleration.
    When following a vehicle with Traffic-Aware Cruise Control active, engaging the turn signal to indicate a move into the passing lane briefy accelerates Model S towards the vehicle ahead..."

    So, my question still stands unanswered, IMHO.
     
  4. Racerx22b

    Racerx22b Member

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    Using a dial on the cruise control stalk you can select from one of 4 (I believe) following distances. I keep it on the closest setting all the time and it is still further than I would normally follow a car in traffic. Using the closest setting in traffic still invites many people to cut in between you and the car in front of you.

    The car will not accelerate until it senses you are passing the car. It will not speed you up to the rear bumper then allow you to dart out around it.
     
  5. Hookemhorns

    Hookemhorns Member

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    So if I'm driving with TACC but not auto steer, and I start the turn signal, nothing happens until I actually change lanes, then it will accelerate by itself?
     
  6. brec

    brec Member

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    TACC, no Autosteer, from memory: it will accelerate as soon as you start the turn signal.

    I can't answer w/r your original question about what happens if you just activate the turn signal but don't leave the lane, but I'd be willing to bet "a lot" that it won't be dangerous. If I remember I'll try it when next on a freeway.
     
  7. brec

    brec Member

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    Just so, with the slight amendment that Tesla renders them as "Autosteer," "Autopark," and, for the others, with initial capital letters.

    However -- change of topic warning! -- I have given up on supplying such corrections except when, rarely, they might actually clarify the specific discussion at hand. The use of "Autopilot" for "Autosteer" is overwhelmingly ubiquitous and usually causes no confusion.
     
  8. Hookemhorns

    Hookemhorns Member

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    That's what the manual seems to say - it accelerates right away. I'd bet "a lot" you're right LOL - if you do get a chance, would you try it and post your experience...how much does it accelerate, how close does it approach the car in your original lane, does it give up and back off if you keep the turn signal on but stay in the lane? TIA
     

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