Adaptive Cruise Control and Road Sign Assist

Discussion in 'Gen 5 Prius Main Forum' started by notspam3, Nov 24, 2025 at 1:53 PM.

  1. notspam3

    notspam3 New Member

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    Do the 2024 Gen 5 Prime XSE cars have the capability to automatically change/adapt the cruise control set speed to the posted speed limit signs using Road Sign Assist?

    I can't remember if this car has the capability and I shut it off, or does it only provide notification alerts if you are exceeding posted speed limits.

    I was driving a VW Golf rental car in Europe recently with this feature and I grew to like it.
     
  2. KMO

    KMO Senior Member

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    Not fully automatically, but it can prompt you with an up or down arrow on the speed limit sign.

    While the prompt is there, a long press of the speed adjustment button in the corresponding direction will set to the speed limit (with a configurable fixed margin).

    ...

    Except it seems that's not present in North American cars. The "Dynamic Radar Cruise Control with Road Sign Assist" section and associated configuration options seem to be missing in your manual.
     
  3. BiomedO1

    BiomedO1 Senior Member

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    In north America RSA simply warns it doesn't automatically adjust your speed. On my software version, the speed sign would be outlined in red if I'm traveling faster than posted. I'm sure there's other versions of the same software like KMO that has an up/down arrow displayed. Another issue would be if there is NO posted speed limit sign while entering a freeway/highway - is the car only going 30 mph on a roadway until it reaches a posted speed sign???? I should probably turn RSA off; since mine does this all the time - it doesn't stop blinking red until I reach a posted speed limit sign a few miles down the highway.:(:mad:o_O I wonder if the car is relaying this false information to my insurance company????:eek::rolleyes: I'd be flagged as a speeder and my rates would escalate based of that false intel.

    Be careful what you ask for........:whistle::censored:
     
  4. Paul Gregory

    Paul Gregory Senior Member

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    I have a 2024, and the best you can do is set it to turn red when you are exceeding the speed limit.
    Best to be super alert at all times, because a few of the things you might expect the car should do.
    it does not do. For example, when someone is stopped up ahead, the car will give you a warning, but it doesn't always stop. You could easily run into them.
     
  5. fuzzy1

    fuzzy1 Senior Member

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    The version in my 2024 RAV4 can be set to different overages before outlining in red. Default is 1 mph over, other choices 2 or 3 mph over.

    Mine usually just blanks out when it understands that I changed roads.

    It also suffers from a stale database. In what was a construction zone several years ago, it occasionally flips to the work zone speeds that were posted there during active construction. It gets corrected each time it sees a new sign, then reverts to the stale database figure a few miles later. Work in that zone ceased before I bought this vehicle, so it never saw those slower work zone limits itself.

    I got the impression that if the driver efficiency scoring feature was turned on in mine, the results were reported to 'the Cloud'. After it dinged me for too-hard braking when I properly stopped for a last-moment yellow light, instead of running the light (there are a number of red light cameras around here), I shut that feature off.
     
  6. VelvetFoot

    VelvetFoot Active Member

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    Especially if you're watching a YouTube video on your mirrored phone. :)
     
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  7. BiomedO1

    BiomedO1 Senior Member

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    When you believe in all the autopilot scam.
     
  8. Paul Gregory

    Paul Gregory Senior Member

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    If I were brain-dead.
     
  9. VelvetFoot

    VelvetFoot Active Member

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    That'd be after the crash.