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Totally lost the brakes!

Discussion in 'Model X: Driving Dynamics' started by mahulkp, Mar 5, 2017.

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  1. mahulkp

    mahulkp Member

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    The other week I came out on Monday morning and sat in the car to go to work. When I pressed the brake pedal went straight down to the floor. No resistance whatsoever. No fading or the like, the car stood still. No braking effect at all. After a few pumping the pedal pressure came back and the brakes felt like usual. Gently I rolled off and test the brakes carefully, everything felt normal. We continued to work, about 20 mile journey and everything worked as it should. When evening came, I left the office and sat down again in the car. Same thing, no braking at all. Fortunately, what the car was flat in the garage and after 3-4 pump the brakes lit a warning "Low brake fluid level - Contact Tesla Service". Not good. However, as the return brake pressure again after some pumping and I slowly rolled out of the garage. It was late at night and I was considering whether I would drive on the brakes but then again worked so I drove home slowly and carefully. No problem, the brake is functioning normally. I figured I call SC tomorrow morning but the other came between them so it took a few days and meanwhile worked the brakes are now back to normal. On Thursday, I called Tesla and got one in the workshop the Monday after.

    Now my car then a week on the SC in Gothenburg. It turns out that the leaked brake fluid out of the container but can not find any leaks. It has torn down the entire brake system and finds no visible faults. The logs can be ensured that the pedal went to the bottom and you also feel my brakes "svampigare" when compared with another car. The case is escalated to Tesla in Fremont and I may not return the car until they solved this. According to the technician at the SC, there are indications that the fault is in the main brake unit but Freemont would like to re-create the error before changing part.

    As always a first-class treatment and handling of my case. Courtesy car, of course, I get daily updates about what they do and how the plan looks like.

    Any one else hos had a similar experience?
     
    • Informative x 4
  2. wcfinvader

    wcfinvader Member

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    Risky move driving it. My brothers ICE had brake failure while he was driving on his way home. He lost enough fluid to result in no brakes. He only made it home thanks to the E-Brake. That's one thing I miss on a Tesla. It's pretty easy for brake failure to happen unfortunately. How would one stop a Tesla with brake failure? E-Brake system works off hydraulic brakes don't they? I have wondered about this ever since my brother had his incident. Even if the E-brakes would still work imagine the ride with it locking the brakes after pushing the button.
     
  3. thimel

    thimel Member

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    The emergency/parking brake is separate from the main hydraulic brakes. If you push the park button for several seconds, it applies the parking break even if you are going at high speed. Someone reported testing this on some thread here.
     
  4. wcfinvader

    wcfinvader Member

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    That's news from me. Never saw that post but that's good to know. I assumed it worked off of the same system. I feel a little safer now knowing that.
     
  5. sladotron

    sladotron Member

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    I had a somewhat similar experience today. I was in a traffic situation where I had to press the brakes hard to stop the car, and the brake pedal went all the way down with a bit of pumping action from the ABS along with a "low brake fluid" message. The car did stop in time but I felt that it wasn't normal breaking behavior. After I released the pedal, the message did go away and the brakes felt firm again.

    I will check the brake fluid level tonight and report back but it definitely is a concern of mine.
     
    • Informative x 1
  6. mahulkp

    mahulkp Member

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    My car is now repaired. The main braking unit (ibooster) had an internal leakage that made this problem. All working fine since then.
     
    • Like x 1
  7. Lasttoy

    Lasttoy Member

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    Look on rear rotor, there are 2 calipers, one normal, one emergency, parking
     
  8. TSLA Pilot

    TSLA Pilot Member

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    No longer true for all Teslas.

    Elon has mentioned "20 hardware changes per week" (or was it "per month?"). One of those changes is the new rear braking system on our Feb, 2017, production MS 90D, although I think it began about 4 months earlier? It has a combined rear caliper with both hydraulic and electro-mechanical brakes in an all-in-one caliper. At least on the MS's going forward, only the "P" versions get a full rear Brembo caliper now, and a separate electro-mechanical Parking/Emergency Brake. (Not "break" by the way! That's a verb and we're talking about a thing, and a thing is a noun.)

    As an aside, one should always be aware that pressing AND HOLDING the "Park" function engages the Emergency Brake on a Tesla, thus bringing the car to a halt should the hydraulic brakes fail. This can also be done via the center display screen. In general, driving a car with no brakes, or brakes that are intermittent, is a bad idea . . . .
     
    • Informative x 2
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  9. sladotron

    sladotron Member

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    For what its worth, I did check the brake fluid level and it appears to be ok. The level is at just below the max mark. Probably will need to visit service center.
     
    • Informative x 1
  10. MS16

    MS16 Member

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    Keep us informed what they find.
     
  11. verygreen

    verygreen Curious member

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    I think I just had something very similar happen to me.
    Tried to brake and suddenly the pedal "fell through" and a "low brake fluid" warning came on.
    Luckily did not hit anything.
    I couple of pumps and the braking restored and the warning is gone, but pedal feels pretty stiff now.
    Called Tesla Service and they told me the car is no longer safe to drive, but I have a scheduled service for tomorrow anyway, so we'll see what they find in the end.
     
  12. Yinn

    Yinn Member

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    In case anyone is wondering...when the brake booster has a leak, you basically get an air bubble where that little bit of fluid used to be in the brake line. Air can be easily compressed where as the liquid brake fluid takes much more force to compress. When you step on the brake pedal, you're feeling that air bubble compress.

    By pumping, you are essentially squeezing the bubble to the point where it can't be compressed anymore and the brakes will function again. But once you release and allow the pressure to flow back, the air will be uncompressed and you will deal with the same squishy pedal. So in an emergency situation, pump like your life depends on it. Just because it feels stiff again, doesn't mean it's safe to drive though.
     
    • Like x 1
  13. verygreen

    verygreen Curious member

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    Well, for me the pedal feels a lot stiffer than before the incident.
    Reminds me of cars without a power brake assist, the play from "no brakes" to "full force" is almost none where as before I remember there was quite a bit of movement to activate the hold mode.
     
  14. SabrToothSqrl

    SabrToothSqrl Active Member

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    I had a brake booster fail while driving down my VERY steep driveway in a 1995 Chevy Tahoe. No power brakes in a vehicle with barely any brakes to start with!
     
  15. verygreen

    verygreen Curious member

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    Just heard from my service center, they now believe the brake problem I experienced is due to an air pocket in brake lines.
    They are going to flush the brake lines and hope the problem won't repeat.
    Time in service this time around is 4 weeks, sigh.
    Hopefully that would be the end of it indeed.
     

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