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Autopilot issues common?

Discussion in 'Model S: Driving Dynamics' started by Viro, Nov 3, 2019.

  1. Viro

    Viro Member

    Apr 30, 2019
    Indiana (U.S.A.)
    New 2018 Model S 75D owner here. Something that makes autopilot almost non usable for me is driving down a four lane Hwy. a car crosses 3-400 feet in front of you and the Model S slams on it's breaks for a second. This almost cause an accident as I had someone tailgating me while I was in the passing lane. It does this a lot, is this normal? All my driving is down these 4 lane highways so people turning out in front of me is quite common.

    I turned the following distance down to 1 car thinking it would reduce the sensor range but it didn't help.

    Any suggestions or learn to live with it or don't use it?

    Thanks for your time.
  2. pedriscoll

    pedriscoll Active Member

    May 30, 2015
    Indianapolis, Indiana
    No, that is not normal. While there is a problem with phantom breaking, it certainly should not occur from a vehicle 400 feet in front of you. I sometimes experience it when a semi is in the lane next to me and drifts close to the edge of it’s lane. I also have thankfully rare spontaneous breaking for no apparent reason at all. I have learned to always be ready to hit the accelerator if there is someone close behind me. This is a real issue with AP 2.5. I never experienced it at all with my previous AP 1 Model S. I would recommend that you have the service center check your camera calibration.
  3. ElectricOrgan

    ElectricOrgan Banned

    Oct 11, 2019
    The trigger in this case is the relative speed of the vehicle in front of you. If they are going as fast or faster you should be fine unless they are really close. But if the car in front is slower than you, a Tesla sees that as a dangerous situation. I see that often when cars pull across or out in front of me. So if a Tesla is being followed too closely it is likely to get someone's grill wrapped up in their bumper. Heck, my car slowed from 65 to low 50's the other day before I realized it was just emotionally upset and I needed to punch the gas... well that's what it's called, the gas pedal! How many people's phones actually ring? It's a figure of speech.
  4. FrederickBound

    Nov 7, 2019
    I don't know if you CAN hit the accelerator fast enough in many cases. I had a tailgater once when I was on a highway with a left hand exit that I needed to take. I knocked back my speed 1 mph at a time and he just got closer. Finally he decided to pass after his headlights were no longer visible below my window (less than 1 car length away). This ticked me off, so I hit the gas as he passed me preventing him from getting by. I slowed up and let him try again and I hit the gas. The third time a bright light shown in my side window to let me know he was a cop. lol I was coming up on my left turn anyway so I let him by.
    • Funny x 3
  5. ScubaMal

    ScubaMal Supporting Member

    May 7, 2018
    Bermuda Dunes, CA
    Last week I had the FSD HW3 computer upgrade done with Software 2019.40.1.1. We went on our first road trip this weekend since the updates. Autopilot now has excessive back and forth weaving in the lanes. It has always been rock solid with staying in the center of the lane before this. Has this happened to anyone else?
  6. r1200gs4ok

    r1200gs4ok Active Member

    Jul 17, 2019
    Irvine California
    I went on short trip yesterday and I found the 40.1.1 with FSD to be very smooth........the auto lane changing was very fast and to me, was much better when approaching an entrance ramp where cars were entering the freeway, it was not trying to find the wider lane, kept right on track.....I did have trouble using the smart summon......the car woke up and backed up then stopped.....could not get it to come to me.....but I think it was operator error......the parking lot was nearly empty and I was in direct sight to the car about 110 feet away......

    all in all......I think 40.1.1 is workin ok for me......will be interested in seeing what I can do with windshield wipers
  7. animorph

    animorph Active Member

    Apr 1, 2016
    Scottsdale, AZ
    It does move to the edge of your lane when a large vehicle is in an adjacent lane. With moderate traffic this causes a lot of weaving. That's a "feature", not a bug, though it could be smoother.

    It does try to center into on-ramp merge lanes if there is no dividing lane line. That's been happening for quite a long time now, so nothing new.

    It does seem to oscillate a bit in corners, exit lanes, and even auto lane changes that don't quite hit the center of the target lane.

    All in all it is somewhat embarrassing to think about what the drivers behind and to the side of me think of this. Kind of the same situation as when AP2.0 was first available, although it is stable on straight roads with no adjacent traffic and unlined on-ramps. I'm sure it will be fixed relatively soon.
  8. dannycamps

    dannycamps Member

    Apr 8, 2019
    Northeast USA
    Prior to v10, I found the car would abruptly slow down if I was approaching an entrance ramp and someone was attempting to enter the freeway to the right of me.

    It's better now in more recent versions (slows down a little bit but no sudden braking) but I still put my foot on the pedal and maintain speed in these situations instinctively now.
  9. Chisale

    Chisale Member

    Sep 28, 2019
    In my opinion phantom braking occurs at such irregular intervals that it's difficult to pinpoint exactly what is causing it. I would say that cars merging in front of you and at a reasonable distance is NOT a good indicator. So if it does that every time to you then in my mind something is wrong with your radar. The most common factor for me in a phantom brake is going under a relatively large overpass on a heavy overcast day. Or with new highway lanes opening into existence or two lanes being condensed down into one. That being said, it's also occurred out in the complete open with no lane factors and in full sunshine. If someone is tailgating you very closely then my recommendation is just to have your foot poised over the accelerator so you can stomp on it with the first notice of it happening. Or just shut off autopilot in those situations. Until they get the issue resolved that is about the best advice I've come up with.

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