Adaptive cruise control shuts down and says “No preceding vehicle”

Discussion in 'Prime Main Forum (2017-Current)' started by Frankcos, Jul 18, 2018.

  1. Frankcos

    Frankcos Junior Member

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    I have a 2017 Prime Advanced. Whenever I’m using adaptive cruise and another car merges right in front of me (usually in slow moving traffic), the cruise shuts off and the screen displays the message “No preceding vehicle”. Not only is this dangerous and annoying, but it doesn’t make any sense, because cruise control does not require “a preceding vehicle”, it can work on an empty road. I took the car to my dealer, and they said they tried to replicate the situation but were unable to, so they won’t do anything about it. Has anyone else experienced this problem, and if so, have you found a solution?
     
  2. schja01

    schja01 One of very few in Chicagoland

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    If under approx 32 mph and preceding car changes lanes adaptive cruise disengages by design. Could this be what you are experiencing?
     
  3. Digloo2

    Digloo2 Active Member

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    I typically bypass the adaptive cruise and turned off the lane monitoring. They started sounding like an annoying back-seat driver everywhere I'd go. The adaptive cruise seems to have an unusually variable depth of field -- sometimes it would alert me when a car would pull into my lane 6-8 lengths ahead, and sometimes fail to detect it at all at reasonably close range. And it's particularly bad dealing with cars merging in and out ahead of me. It seems to recognize when cars leave the lane, but not when they cut in ahead of me. This is especially annoying on the freeway. When a car leaves the lane, it will start to accelerate to fill the gap, but if another car then cuts in, it doesn't notice. I'll start to swerve to avoid the car ahead and I end up getting a lane warning when it should have slowed down because a vehicle cut in front of me.

    A few times in slow traffic it would flash and sound a warning while I was dealing with the car in front suddenly slowing down. There's no way in hell I could react to that flash and buzzer in time. However, in every instance, I was already aware of the issue and was already breaking. I've often wondered if the car would stop itself if I didn't hit the brake in time, or just make noise like an annoying 3-year old and collide with the vehicle in front. (I'm tempted to find out, but I'm sure Toyota has some fine print somewhere that would allow the insurance company to get out of covering the accident.)

    This technology is far to inconsistent for me to trust it, although it's really cool that it will sometimes slow down and stop at a light when there's a car in front of me; unfortunately, it doesn't start moving again without a nudge.

    But a few times there was a long way to a red light and cars were already stopped, and the look-ahead radar couldn't tell there was either a red light or that there was a vehicle stopped there. No flashing light, no warning buzzer, but I had to jam on the brake with only a short distance left to travel because it never started to slow the car down. I think I would have hit the stopped car ahead of me at full speed.

    And it seems unable to recognize traffic signals like red or green lights.

    I can't wait until I can get a self-driving vehicle. But I suspect we'll never see Toyota upgrade our equipment beyond the beta-stage software they installed at the factory. At this point, I wish they could just remove it and stop pretending it's at all useful. It's DANGEROUS! They probably even say as much in the manual.

    They should have a way to disable it until they can upgrade it to something more reliable. But I don't see in-the-field software updates happening from any traditional car maker any time soon.
     
    jaqueh likes this.
  4. SteveMucc

    SteveMucc Active Member

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    that's why they tell you to always pay attention. these are driver aids, not driver replacements. It also pops up a message telling you to only use it on a highway so you really shouldn't be using it on roads with traffic lights, or if you are you need to pay attention yourself.

    that said, I really like it... personally I frequently travel a couple hundred miles one way to see my grandkids once very couple weeks. all highway. the adaptive cruise really helps.

    I've also used it in heavy bumper to bumper traffic in NYC and it also really helps there. I wouldn't every want a car to start moving from stop without having much more complex sensors. I cant tell you the number of times people j-walk in between my car and the one in front of me. if the car started to move by itself it could be really bad.

    I can imagine tesla getting sued for one of their cars running over a small child when being recalled from a parking spot.
     
  5. schja01

    schja01 One of very few in Chicagoland

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    Lexus resumes automatically. It also synchronizes the clock to the GPS. Why Toyota doesn’t baffles me.
     
  6. SteveMucc

    SteveMucc Active Member

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    different companies, different lawyers. Everyone has their own threshold of liability. After the "unintended acceleration" fiasco, I doubt the brand could survive the car automatically running over a pedestrian, so suspect they're being very conservative.
     
  7. CharlesH

    CharlesH CA HOV Decal #5 on former PiP

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    Lexus is the upscale Toyota brand. Same lawyers.
     
  8. FuelMiser

    FuelMiser Senior Member

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    To the OP: is your smooth Toyota emblem on the front (the radar sensor) clean?
     
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