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Brakes pulling in turns

Discussion in 'Gen 2 Prius Main Forum' started by Sky, May 4, 2005.

  1. mdacmeis

    mdacmeis Member

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    Prime Advanced
    <div class='quotetop'>QUOTE(GAGendel\";p=\"87499)</div>
    Watch the speedometer carefully when this occurs. I believe you will find it occurs at 8 mph, the point where regenerative braking becomes ineffective and full hydraulic braking is metered by the brake controller. Some vehicles are more noticeable than others. There is simply not enough hydraulic braking metered into the system at the transition point. The system quickly gets back to the desired deceleration, which is noticed if you keep your foot in the same position. You get uniform decel until about 8 mph, a slight loss of decel, then your target decel returns. All in all, I find the brake system is much more linear than most even with this characteristic.
     
  2. mdacmeis

    mdacmeis Member

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    2018 Prius Prime
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    Prime Advanced
    <div class='quotetop'>QUOTE(Sky\";p=\"90040)</div>
    OK, now things are adding up. You have VSC and you have instances of counter steering on curvy roads. The Prius with VSC has steering assisted VSC. What this does is reduce assist in the direction the control algorithm determines is not the correct direction to steer out of a skid. Assist is boosted in the correct direction. The loss of assist may feel like the car steers itself as the sudden loss of boost will effectively stop the steering wheel motion in the direction opposed to assist. I sounds very much like you are getting VSC hits. This could be caused by several things, including a bad speed sensor or sensor tone wheel (tone wheels on the front axle shafts), a bad "gyro" sensor (the latitude and longitude sensor used for VSE in addition to the yaw sensor for ABS), or a computer problem causing either the skid ECU to request steering changes or the steer ECU incorrectly doing its job. Sounds like a job for the technician with a scan tool so they can monitor variables when the problem is recreated.
     
  3. DanMan32

    DanMan32 Senior Member

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    First, if VSC was kicking in, the squiggly car would blink, and a chime would be heard.

    ABS would only have the squiggly car blink, no chime. Same for Traction control.

    Second, the yaw sensor is strictly for VSC. The yaw sensor module also has a deceleration sensor. This module doesn't exist if you don't have VSC. ABS only uses individual wheel speed sensing.
     
  4. Sky

    Sky New Member

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    Very strange.
    As upset as I am with this steering situation, I keep finding myself making up reasons to drive to the store; any store, for anything. And hey, while I'm at it, why not take the long way there--and back. It won't cost hardly anything for gas!
     
  5. Sky

    Sky New Member

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    Who'd have thought a spike through the tire was a good thing?
    This happened to me Sat., 3 days ago. Jack and lug wrench all worked well. Then I re-read a number of posts in other places in Priuschat, specifically about steering response and tire choice. Based on what I read I decided to change all 4 tires, going to the Goodyear "Assurance" comfortread. And am I ever glad I did.
    What a difference. It completely changed the steering wheel feedback! I no longer find myself "frozen to the wheel" because of strange sensations. I haven't had any of the "pulling while braking in right turns", and driving is once again the fun experience it always used to be for me. Not only is the steering feel dramatically improved, but the ride is noticably smoother also.
    I'm not sure what effect the tire change has had on gas milage, being as our temperatures took a 20 degree jump from the low 70's to the low 90's so I've had my air conditioner on. I was averaging about 48 mpg, and now according to the consumption screen, I'm at about 46 mpg.
    I want to thank all the people who posted here, and in other places in Priuschat, for sharing thier experiences. I am so glad I took a chance and tried the Comfortread, as it has taken my appreciation of my Prius to a whole new level.