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LCA? LTA? 2024 Prius fights me for the steering wheel!

Discussion in 'Gen 5 Prius Technical Discussion' started by jmcquaid, Feb 28, 2024.

  1. jmcquaid

    jmcquaid New Member

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    I've had this car one week and I'm hating the driving the experience. Yes, everything is smooth and generally fine. But on the highway, like commuting, the steering fights me on every lane change.

    I've been trying to figure out how to turn this off but so far unsuccessful. I'm ready to sell the car and mad at myself for basing my purchase mostly on my wife's 7 year old Prius which lacks this intrusive feature.
     
  2. Jerry G

    Jerry G New Member

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    LCA can be turned off. Look it up in the owner’s Manuel. It’s a pretty easy fix.
     
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  3. Beach Dweller

    Beach Dweller Junior Member

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    My 2024 acts this way if the lane keeping switch is on and adaptive cruise.
    If you want to change lanes, depress the turn signal, and release when it has completed the change.
    To return to the original lane, repeat the action.
    Or, you can keep the lane keeping switched off.
     
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  4. Trollbait

    Trollbait It's a D&D thing

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    Are you using turn signals?
    Using cruise control?

    There are two systems. LKA is on all the time. It gives a warning and a nudge when the car gets too close to a line. It can be turned off in one of the settings menus.
    LTA is the one that auto steers the car to keep it in the lane. It only comes on with the dynamic cruise control. There is a button to turn it off on the steering wheel.
    Putting on the turn signal temporarily disables both.
     
    #4 Trollbait, Feb 28, 2024
    Last edited: Feb 28, 2024
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  5. Zeromus

    Zeromus Member

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    LCA (Lane Change Assist) is a feature of DRCC (Dynamic Radar Cruise Control) if equipped. When you're using the advanced cruise control, if you hold the turn signal in place without clicking it all the way, the car will change lanes for you when/if it is safe to do so while maintaining speed.

    Lane Tracing Assist is just the feature that tracks where the lines on the road are and the center of the lane. It also works with DRCC by offering "gentle" steering assist to make it easier to follow the road when driving.

    Lane Departure Alert is probably what you're actually feeling. This is the one where, if you're crossing or getting to close to the lines of the road the car has detected *without* using turn signals prior to approaching those lines, the car will use stiffer feedback to get you to put the car back in the centre of the lane. If you aren't signalling early enough the car thinks you're drifting - which is dangerous - and is trying to tell you you're drifting.

    Helpful if you're driving and actually falling asleep at the wheel. Not helpful if you're fully aware - other than making you build a better turn signal habit ;)

    I've only felt it once since getting the car last month and driving 1,000kms now. And it was when I forgot to signal.
     
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  6. dbstoo

    dbstoo Senior Member

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    I've only 2,000 miles on mine and I'm learning. :) A few things that are similar to the OP's complaint revolve around tracking the right lane marker VS the left side.

    The first time that the car tried to make a sudden pull to the right was when I was on a San Diego Interstate with very light traffic. I was traveling in the slow lane. As I passed an off ramp the solid white line on the right receded to the right while the left broken line went straight ahead. The car followed the right line until I over-rode it by simply turning the steering wheel.

    As mentioned above, the design will resist a lane change that will cause a collision with nearby automobiles.
     
  7. JJNY

    JJNY Junior Member

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    It was mentioned above, but using a turn signal will allow lane change.
     
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  8. Trollbait

    Trollbait It's a D&D thing

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    These systems can also confuse cracks in the pavement and shadows for lines.
     
  9. Zeromus

    Zeromus Member

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    Thankfully haven't had that happen yet. But if it did happen often, I guess I'd turn it off.

    So far I've found no issues with the supportive systems, but I also drive in a major city so I'm sure that helps. I also did turn down one or two of the feedback systems though since when I was intentionally pushing them to see how they worked (on empty safe to do it on roads) since they felt a bit strong.

    The biggest one I had issues with was the pre-collision braking support, with the follow distance for DRCC setting set to max. It was a bit aggressive and it was reading cars that poorly park on the side of the road as actually being on the road, so it would engage the brake when I would take my foot off the gas to coast by them. Though maybe that's not right. Since the car would probably try to slam the brake if it thought the car was *in* my lane ahead of me. It was probably just trying to apply some brake power to make stopping in case they open their door suddenly, or pull out randomly, easier. Kind of like when you're taught to hover the brake in case of sudden pedestrians/opening doors when passing parked cars, but with much more pressure.

    I adjusted the strength of the support down from default to 1/3 and its fine now.
     
  10. jmcquaid

    jmcquaid New Member

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    I did find out how to turn off the intrusive steering function. It seems to me that Toyota is trying to implement the beginnings of the self-driving Prius. Which, from a technology standpoint, I find arrogant and dangerous. I am very unhappy with the concept that the car will instruct me in how to drive properly. And, of course, cars are beginning to instruct insurance companies about how to increase rates on selected drivers. Those drivers may be hot-headed and dangerous or merely enjoy driving, of course.

    I guess I'm okay with the things being turned off, although I'm still concerned that the car is going to impose some move or constraint unexpectedly. And, of course, the far bigger issue is privacy and surveillance capitalism. But that's for a different forum I guess.
     
  11. 2023p

    2023p Member

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    Drivers should be using a turn signal. When turn signal is activated you no longer will be fighting against the car or safety. Please drive safe and use your turn signals.
     
  12. TMR-JWAP

    TMR-JWAP Senior Member

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    Laughing so hard as I was reading this.
    Telling us that you never use turn signals when changing lanes, without actually telling us, lol.
    Looks like the car is trying to teach you better driving habits.....
     
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  13. Gokhan

    Gokhan Senior Member

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    Prius does not have LCA. Only Prius Prime has it.
     
  14. Gokhan

    Gokhan Senior Member

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    As others said, lane-keep assist (LKA) is trying to keep you in your lane because you are not signaling when you change lanes.

    You don't get lane-change assist (LCA) on the Prius HEV. It is only available on the Prius Prime PHEV.

    Lane-tracing assist (LTA) will only function if you explicitly turn on dynamic radar cruise control (DRCC) with LTA.
     
  15. Lantaral

    Lantaral Junior Member

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    Had the same problem. It only occurred on vacant roads where I didn't feel the need to use the turn signal to move into a turn lane. When using the turn signal, no issues.

    The reason it needs the turn signal is because the system cannot read a driver's mind. The only way for the car to know that crossing over a lane line is not an unintentional drift is for the driver to actually use their turn signal.

    The car is working perfectly. The system is working perfectly. The problem isn't the car, it's the nut behind the wheel. ;)
     
    #15 Lantaral, Mar 20, 2024
    Last edited: Mar 20, 2024
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  16. rhodes2020

    rhodes2020 Junior Member

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    Okay, everything written is good stuff, and true. BUT my new 2024 with 700 miles. Page 305 of manual describes LCA and page 626 describes how to set to off. And I want to set it to off for now. My Question Is: how to get into that setting. I am
    logged in to my car with an email and password, I have the app working. The screen has a Manual Settings choice, and when I select, it says login to your account. Which I already am, so I do it again, and it puts me on same screen. Manual settings are not opening. In the other settings are there are lots of choices, like Customize drive
    mode, but no LCA choices.
    So although I understand how it should work, I cannot get to the area to make the changes.
     
  17. KMO

    KMO Senior Member

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    No idea about the app, but it's column "B" on those tables, which means you have to do it via the instrument cluster. It's under the settings (cog icon) menu tree. Instructions in page 167 or so of the manual.
     
  18. rhodes2020

    rhodes2020 Junior Member

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    The manual Settings Menu keeps asking me to
    login, even though I am
    logged in (logged in to car and to app).
    it just loops back to manual settings, cannot
    login.
    Under Customize Settings menu cannot find the LCA switch/setting as described in the owners manual
    on pages 305 and page 626.
     
  19. KMO

    KMO Senior Member

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    Are you looking at the multimedia screen? It's on the instrument cluster.
     
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  20. TMR-JWAP

    TMR-JWAP Senior Member

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    Are you trying to disable LCA or LKA?

    You hate using turn signals that much, that you would rather deactivate the safety feature instead?
    The turn signals on our new 2024 Santa Fe also activate the side/rearward viewing camera(s?) that give a really nice view of whichever side of the car you're turning toward.

    With today's systems being so 'linked', you'll probably get a notice from your insurance company in a week or two letting you know your rates are going up due to disabling safety features.
     
    #20 TMR-JWAP, May 23, 2024
    Last edited: May 23, 2024
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