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2020 Prime Steering effort changes unexpectedly

Discussion in 'Prime Main Forum (2017-2022)' started by Peter P, May 23, 2020.

  1. Peter P

    Peter P New Member

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    This is probably a "feature" but if so, it's a very disconcerting one.

    While driving, at times the amount of force required to turn the steering wheel becomes somewhat lighter than normal, causing me to over-steer, i.e. to turn the steering wheel more than I intended.

    If a feature, can it be disabled? If not a feature, has anyone noticed this in their own vehicle and had it fixed?
     
  2. bisco

    bisco cookie crumbler

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    prius has speed controlled power steering. the slower you are going, the more assist you get. but i have never noticed a major difference, it is supposed to adjust to keep effort at similar rates
     
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  3. davecook89t

    davecook89t Senior Member

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    Is Lane Departure Warning/Steering Assist enabled when you have noticed this? Would disabling it make a difference? Possibly the camera that controls that function needs to be calibrated.
     
  4. Peter P

    Peter P New Member

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    We do have the Lane Departure Warning turned on all the time, and occasionally it reacts to me getting too close to the centre line or curb line, but I can't say that I've noticed any correlation between these warnings and the sudden change in steering effort. I'll make a point of watching for that.
     
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  5. Salamander_King

    Salamander_King Senior Member

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    I never noticed a sudden or any change in steering effort in my 2017 or 2020 PRIME. Does this happen in highway drive or any particular speed?
     
  6. Peter P

    Peter P New Member

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    I've noticed it at city speeds and also on a stretch of road posted 70 kmh.
     
  7. Salamander_King

    Salamander_King Senior Member

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    So, what about at above 70kmh on highway speed? I have never noticed it on my previous 2017 PRIME when I drove on a rural road at 30mph (48kmh) or on an interstate at above 65mph (105kmh), but I have not driven my new 2020 PRIME on a highway yet. Maybe something has changed. I don't think I have noticed any change in steering characteristic on my 2020 PRIME when driving around town, but with COVID-19 restriction, I have no plan to do highway drive anytime soon, but when I do, I will keep it in my mind to check the steering effort.
     
  8. Peter P

    Peter P New Member

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    I've only driven at highway speeds once or twice since we bought the car, and not recently, so I can't remember if this problem cropped up then or not. But it's been a regular thing at city speeds and at 70-ish kmh.
     
  9. Leadfoot J. McCoalroller

    Leadfoot J. McCoalroller Senior Member

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    Fair chance this is it. Our Prius has the warning system, it'll beep if it thinks we aren't coloring between the lines. It does NOT have the active steering system that physically influences the wheel.

    I have rented two other Toyotas that did have the full active steering setup, and it's very noticeable- you always get more power assist in whatever the computer thinks is the correct direction.
     
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  10. schja01

    schja01 One of very few in Chicagoland

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    I’ve noticed a correction ONCE when I intentionally pulled off to the shoulder and crossed the white line without signaling and no one was behind me. It started beeping fairly early but the correction was microscopic and only when half the car had crossed the line. :(
     
  11. Salamander_King

    Salamander_King Senior Member

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    FYI, I usually have the Lane Departure Warning turned off, except during long highway trips. That may explain why OP is having this problem (or feature).
     
  12. Peter P

    Peter P New Member

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    Well. I just did a 20 km out-and-back trip. LDW (lane departure warning) was off for the outward segment, on for the return. Speed zones were approximately half of the trip at 50 kmh and half at 70 kmh.

    With LDW off, I didn't notice any of the events mentioned in my original post. As expected, crossing the centre line had no effect.

    On the return portion, with LDW on, crossing the centre line resulted in the usual beeping and flashing displays, but no perceptible change in steering effort in either speed zone. However, I noticed two reduced steering effort events in the 50 kmh zone, not correlated with centre line crossings.

    I don't mind disabling LDW, especially since I won't be doing any highway driving in the near future, but the occurrence of these reduced steering effort events does seem to me to be more of a bug than a feature. And they're disconcerting.
     
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  13. Salamander_King

    Salamander_King Senior Member

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    Sound like LDW has something to do with the steering. I agree the description seems a bit odd that the reduced steering is not happening when the LDW is triggered. As I find LDW feature to be useless during most of my driving situation, I have it turned off. I don't think I noticed any steering effect when I tried using it on my regular commuting route with my previous 2017 PRIME, but I have not tried using LDW on 2020 PRIME at all. I will give a try next time I drive to see if I have the same problem.
     
  14. PT Guy

    PT Guy Senior Member

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    "While driving, at times the amount of force required to turn the steering wheel becomes somewhat lighter than normal,"

    I have not noticed this on my 2017. It is possible that the lane departure warning & assist has been recalibrated for 2020. For 2017 the assist to re-center is almost non-existant.

    Can you find a situation where you can make this happen every time? If you think this is a problem that needs repair, find a way you are certain to demonstrate it to the service writer or tech who can ride along with you. Little is more frustrating than taking the car in for a warranty claim repair and get the response..."cannot duplicate the problem."
     
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  15. Peter P

    Peter P New Member

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    That's the challenge, isn't it? It seems to be random so far, but of course, something is making it happen. Whether or not I can identify what it is remains to be seen. More experience driving the car is required.
     
  16. m8547

    m8547 Senior Member

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    The feature is officially called Lane Departure Alert with Steering Assist. You can tell when the steering assist is active because a little green light turns on briefly on the gauge cluster (near the green cruise control indicator). It's easy to miss it because it's way off to the side.

    Steering Assist comes on then you're close to the edge of a lane. It usually gives up if you're over the line completely. It is very weak. Like a gust of wind trying to push the car back into the lane. It is difficult to get it to reliably activate. It is programmed to be very unobtrusive, so it will not activate or let you overpower it any time it thinks you're making an intentional move. When it's on it will only be active for a few seconds at most.

    The amount of steering assist seems to be independent of the lane departure alert sensitivity. You can set that to normal or high, but high just beeps more without helping you stay in the lane more.