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Change in brake pedal suddenly: any significance?

Discussion in 'Model S: Driving Dynamics' started by brianstorms, Feb 3, 2014.

  1. brianstorms

    brianstorms Member

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    In the past 3-4 days I have noticed a change in the way my Model S feels whenever I get in it when it's parked and I turn it on by pressing the brake pedal.

    It's the feel of the brake pedal that has changed. I have owned the car since Aug of 2013, and every single time I have ever started the car I have put my foot on the brake pedal and the pedal has had only some resistance -- it goes down pretty far.

    But in the past few days, when I get in the car to go somewhere, I put my foot on the pedal and it is HARD, the resistance is really harsh, and I feel like I have to actually PUSH the brake pedal a little bit to go from "Car Off" to the car being on.

    Anyone ever noticed this in their car? What does it mean? Why the sudden change? I only have ~5700mi on the car by the way.
     
  2. Apoclyps

    Apoclyps Member

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    Did you allow the car to "wake up" prior to pressing on the brake pedal? It isn't until the car wakes up does the brake pedal "unstiffen" (at least in my experience).
     
  3. brianstorms

    brianstorms Member

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    Well, I haven't changed *my* behavior, the car changed its -- that's what struck me as surprising and unexpected.

    I just walk up to the car in the garage, or in the parking lot at work, and get in, put my foot on the pedal, and it is extremely stiff. This is an entirely new phenomenon just in past 3-4 days. I haven't done any firmware updates so I don't know why it changed.
     
  4. stevezzzz

    stevezzzz R;SigS;P85D;SigX

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    I've noticed the brake pedal stiffness, but only when the car isn't fully awake yet and won't let me put it into Drive. There seems to be a fairly wide variation in the length of time between door handle extension and ready-to-Drive, though I haven't really made a study of it.
     
  5. AnOutsider

    AnOutsider S532 # XS27

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    Yep, same here. OP, do you have sleep mode on?
     
  6. brianstorms

    brianstorms Member

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    Honestly, I don't actually know. I suppose so.

    I do see the car "boot up" -- you know, show the T logo in the dashboard display, and then ... actually, come to think of it, since the last firmware change that everyone got a few weeks ago, I haven't seen the T logo anymore, the car is basically always awake, just says "Car Off" in the center circle area of the dash display when I get in. Maybe I have sleep mode off?

    But I'm baffled as to why the car behavior would suddenly change when nothing about how I interact with the car has changed. Always a bit unsettling, these computers-on-wheels.
     
  7. 4EG-KC

    4EG-KC New Member

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    There is a way to fix the brake pedal problem . But if you change anything no matter what it is . Tesla will no longer work on that car . The contracts and warranty is no good . Like I didn't like the ON/OFF mode or the Wake up Mode so I put a finger scanner on it instead . Works grate but the oil on your finger's is bad for the screen so you have to put a screen saver on it 2 time a year . There are 2 Rules if you try this . 1, Must have a Override Key . 2, There need's to be some one that you trust to scan in also. Like wife or some one that can drive your car other than you.
     
  8. yobigd20

    yobigd20 Well-Known Member

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    say whaaaaaaaaaaaaaaat? I think someone had a little too much drinky-drinky last night.

    that actually brings up a good point though. How would one of those DUI systems (ignition interlock) work on the Model S? (sort of a rhetorical question, since the obvious answer is that they cannot)...

    The Determinator Ignition Interlock System

    Smart Start® - Ignition Interlock Devices Home Alcohol Monitoring Systems

    Interlock Ignition Device | Car Breathalyzer | DrivingLaws.org
     
  9. mnx

    mnx 2013 P85

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    #9 mnx, Feb 4, 2014
    Last edited: Feb 5, 2014
    I have a hard brake pedal occasionally while trying to turn the car "on". I don't believe my car has an issue or anything like that but it has happened sporadically over the last year.

    For completeness, it's just because the vaccum pump hasn't run recently to provide brake boost ie. I believe after the car has been sitting a few days.

     
  10. sfriedrich

    sfriedrich Member

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    I have noticed this for the last week. It really stood out to me when it first happened and it has continued. I'm still on 5.8.4 so there's been no software change. Kinda puzzling.
     
  11. AmpedRealtor

    AmpedRealtor Active Member

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    This is normal behavior if the car has been sitting for a while. The vacuum in the brake line bleeds out over time, stiffening the pedal. Once the car turns on, the vacuum is restored and all is well. All of my previous cars functioned in more or less the same way.
     
  12. caddieo

    caddieo Member

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    Same here. It is stiff first time in the morning (along with slow response of door handles to the fob). No problem with subsequent drives during the rest of the day.
     
  13. brianstorms

    brianstorms Member

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    I'm noticing it's even stiffer today. And it's not just getting the car out in the morning. At noon I took the car to get some lunch and noticed it the brake pedal was like a rock.

    This is an entirely new phenomenon that seems to be worsening. Time to talk to Tesla.
     
  14. cinergi

    cinergi Active Member

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    I've had this happen randomly -- haven't been able to correlate it.
    Normally it's somewhat stiff. Sometimes it's REALLY stiff (I'm thinking about the same level as you're describing, because it's almost shockingly stiff). But not always.
     

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