One safety feature keeps trying to kill me

Discussion in 'Gen 5 Prius Technical Discussion' started by cool_prius, Aug 18, 2025.

  1. KMO

    KMO Senior Member

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    It's LDA ("Lane Departure Alert"), one of the top-level entries in the three pages of under the settings tab with the cog icon.
     
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  2. Gokhan

    Gokhan Senior Member

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    It is not confusing anything. It is trying to keep you in your lane. It is called lane-keep assist (LKA). It is a very useful feature.

    It also sounds like you are not driving in the middle of the lane. It happens a lot on LA freeways. People bulge into your lane when they pass you. It is dangerous and annoying.
     
  3. cool_prius

    cool_prius Junior Member

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    I don't think so since it's not just an alert.
     
  4. cool_prius

    cool_prius Junior Member

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    What I'm trying to say is that it attempts to pull me out of the lane I'm in. So if I let it, it would steer me into the next lane over, causing a crash. I wouldn't have made this thread if it was steering me towards the center of the lane.
     
  5. cool_prius

    cool_prius Junior Member

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    My first post in this thread was just one theory. Another theory is that it's picking up old lines, cracks, or other imperfections on the road that aren't lane markers, and getting confused where the lanes actually are. Or maybe it's when a glare from a car hits the front camera just right. I've been noticing the glare thing a lot happening with the backup camera actually. It alerts as if there's something passing, I take a closer look, and it's just the sun being bright.
     
  6. Gokhan

    Gokhan Senior Member

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    I don't think this behavior was ever reported. Perhaps it happens in a fork etc. where the lane splits and there are multiple lane marks.

    The other possibility would be a defective system, which could be because of a dirty windshield, improper calibration, etc.
     
  7. Gokhan

    Gokhan Senior Member

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    Well, BSM/RCTA use the rear corner radars, not the backup camera.
     
  8. cool_prius

    cool_prius Junior Member

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    I mean it does try to steer sometimes when a lane merges or splits, like next to exits. But to me that feels completely normal and expected. I don't consider that to be a part this problem.

    A dirty windshield being the source of such a problem seems questionable. If there's even the smallest chance that a dirty windshield can make the car start swerving, then the driver should absolutely be able to disable it.

    Bad calibration does seem more likely. I went to the service center the day after I bought my Prius because the steering wheel didn't turn as easily compared to the one I test drove. Thought it could've been an issue with the power steering, but the techs didn't find anything wrong. Later I realized that I had LTA enabled so turned it off, and the steering wheel stopped being difficult to turn. But this gets even more strange now that I'm learning that LTA is only supposed to work when DRCC is on? I never use DRCC.
     
  9. cool_prius

    cool_prius Junior Member

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    I assumed it used the camera because it stops alerting after I stop and wait a second, so it felt like a thing caused by a camera being slow to focus. Now I'm curious about what's actually happening there.
     
    #29 cool_prius, Aug 23, 2025 at 8:43 PM
    Last edited: Aug 23, 2025 at 8:48 PM
  10. KMO

    KMO Senior Member

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    That phrase covers both the alert and the auto-steering, despite the wording. You seem sufficiently invested in this that you could actually read the manual to find out what the car does, rather than post incorrect non-accepting guesses on a forum.
     
  11. KMO

    KMO Senior Member

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    LTA does only work with DRCC and is controlled with a dedicated steering wheel button.

    It sounds like you turned off LDA in settings.

    You need to pay attention carefully with all these confusing nearly-identical acronyms - thanks, Toyota.
     
  12. Gokhan

    Gokhan Senior Member

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    You can set the DRCC to the lowest possible speed and then use the gas pedal to control the speed. That way LTA will work and you can use the gas pedal normally.
     
  13. Gokhan

    Gokhan Senior Member

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    BSM/RCTA use the radar. BSM does not work at very low speeds or with the vehicle stopped.
     
  14. Prodigyplace

    Prodigyplace 2025 Camry XLE FWD

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    Used in an undocumented hierarchical Settings menu :(
     
  15. Trollbait

    Trollbait It's a D&D thing

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    That is quite likely. Happens with the Subaru; even had it mistake power line shadows for lines.