# Emergency brake?



## NYer (Dec 11, 2018)

Something that I have been trying to figure out is where is the emergency brake? Clearly there is none on the floor nor near/above the console. 

Is the idea that the Tesla brakes never fail and so a redundant braking system is not necessary, unlike every other car I've driven in the past?

Yes, I know that there is a parking brake for incline parking, but after reading the manual, it does not seem like I should be slapping the parking button if my brakes go out on the highway.

I might be entirely overlooking something here. Please let me know if I am... Thanks!


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## skygraff (Jun 2, 2017)

Hi,

As weird as it may sound, the manual puts the info about this under Emergency Braking but it isn't the main body of that section. Instead, it's a caution paragraph in the next column:


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## JasonF (Oct 26, 2018)

Like a lot of newer cars, Teslas have an electric parking brake. You can apply them by holding down the park button on the stalk, but you won't be able to control the braking force with it.

You can also use regenerative braking to slow the car without using the brakes, if they fail.


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## Ed Woodrick (May 26, 2018)

If I remember correctly, you can hear the brakes being set once you shift into park.


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## Klaus-rf (Mar 6, 2019)

Press in on the right stalk button - the same one you use to engage "Park" when stopped.

While moving, hold that button in for more than one second and the rear electric motors on the calipers will start to engage. I've never had the wheels lock, but YMMV. The car will shudder to a complete stop or until you release the park button on the stalk.Steering is not affected.

EVERYONE should practice this at least once just to know how it works.


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## NYer (Dec 11, 2018)

skygraff said:


> Hi,
> 
> As weird as it may sound, the manual puts the info about this under Emergency Braking but it isn't the main body of that section. Instead, it's a caution paragraph in the next column:
> 
> View attachment 39283


This is very helpful. Yes, I see it in the manual now.

I'm just envisioning myself going down the highway at 65 MPH, brakes are out, and I have to hit a little button at the end of a stick to stop the car. Whereas, I was brought up either pulling a hand lever or slamming my foot on an emergency brake pedal. Not that intuitive.

Good info - appreciated.


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## JasonF (Oct 26, 2018)

NYer said:


> I'm just envisioning myself going down the highway at 65 MPH, brakes are out, and I have to hit a little button at the end of a stick to stop the car. Whereas, I was brought up either pulling a hand lever or slamming my foot on an emergency brake pedal. Not that intuitive.


It's also much less likely to happen than on a gas car, because you can always let the resistance from the electric motor (regen) slow you down, and it's pretty good at it. To be totally out of control, you would have to have the drive shafts disconnect or the electric motor go runaway, AND the brakes go out at the same time.


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## NYer (Dec 11, 2018)

JasonF said:


> It's also much less likely to happen than on a gas car, because you can always let the resistance from the electric motor (regen) slow you down, and it's pretty good at it. To be totally out of control, you would have to have the drive shafts disconnect or the electric motor go runaway, AND the brakes go out at the same time.


Well look, I love the transfer of energy from the wheels to the battery when I let off the accelerator to slow down. I also love saving brake bad. That said, in an emergency braking situation, the regenerative braking is not going to cut it. I'm talking about a car cutting my off, a pedestrian stepping off of a sidewalk, etc. Situations where you have to stop quickly, but the main brake fails for one reason or another - very unusual, hope it never happens, but need to stop immediately.


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## FRC (Aug 4, 2018)

Regen and steering would be your best bet in those situations. By the time you realize braking is gone, after a few pumps, it'd be too late for an emergency brake stop.


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## NYer (Dec 11, 2018)

FRC said:


> Regen and steering would be your best bet in those situations. By the time you realize braking is gone, after a few pumps, it'd be too late for an emergency brake stop.


I agree given that I need to slap a sideways button on the tip of a stick... If it were a handbrake or floor pedal, I'd stand a better chance...


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## JasonF (Oct 26, 2018)

NYer said:


> Well look, I love the transfer of energy from the wheels to the battery when I let off the accelerator to slow down. I also love saving brake bad. That said, in an emergency braking situation, the regenerative braking is not going to cut it. I'm talking about a car cutting my off, a pedestrian stepping off of a sidewalk, etc. Situations where you have to stop quickly, but the main brake fails for one reason or another - very unusual, hope it never happens, but need to stop immediately.


I have bad news there - even an old fashioned pull-up e-brake is not going to have enough power to bring you from 60 to zero before you hit that pedestrian. Those only activate two of the brakes, and the _weakest_ two, using only the power in one of your arms, transmitted by a very flexible steel cable. And then the rear of the car will fishtail, and you'll lose most of your ability to steer.


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## NYer (Dec 11, 2018)

JasonF said:


> I have bad news there - even an old fashioned pull-up e-brake is not going to have enough power to bring you from 60 to zero before you hit that pedestrian. Those only activate two of the brakes, and the _weakest_ two, using only the power in one of your arms, transmitted by a very flexible steel cable. And then the rear of the car will fishtail, and you'll lose most of your ability to steer.


Perhaps in terms of time, momentum, and general physics - you might be entirely right. However - flexible steel cable? My older cars had hand brakes and they were very responsive.

No disagreement re: your mentions of it only impacting 2 of 4 wheels, the risk of fishtailing, etc.


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## Ed Woodrick (May 26, 2018)

NYer said:


> This is very helpful. Yes, I see it in the manual now.
> 
> I'm just envisioning myself going down the highway at 65 MPH, brakes are out, and I have to hit a little button at the end of a stick to stop the car. Whereas, I was brought up either pulling a hand lever or slamming my foot on an emergency brake pedal. Not that intuitive.
> 
> Good info - appreciated.


???? If you are going down the highway and at 65 MPH, brakes are out, who cares?
Regenerative braking is your friend!


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## NYer (Dec 11, 2018)

Ed Woodrick said:


> ???? If you are going down the highway and at 65 MPH, brakes are out, who cares?
> Regenerative braking is your friend!


You haven't driven in California in the HOV lane in rush hour... Regen is great - but takes a while and is not meaningful in an emergency.


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## Ed Woodrick (May 26, 2018)

NYer said:


> You haven't driven in California in the HOV lane in rush hour... Regen is great - but takes a while and is not meaningful in an emergency.


And how many times have you had the brakes fail while in the HOV lane in rush hour and regen wasn't enough? I suspect that it has happened as many times as it has while the car was 2,000 leagues under the sea. Never?
since regen will bring you to a stop pretty quickly, I highly suspect that by the time that you realize that the brakes have failed and remember what button to hit, that regen will already have the car at a stop.


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## NYer (Dec 11, 2018)

Ed Woodrick said:


> And how many times have you had the brakes fail while in the HOV lane in rush hour and regen wasn't enough? I suspect that it has happened as many times as it has while the car was 2,000 leagues under the sea. Never?
> since regen will bring you to a stop pretty quickly, I highly suspect that by the time that you realize that the brakes have failed and remember what button to hit, that regen will already have the car at a stop.


Right... It will have stopped due to the crash before regen does the job or before anyone reaches for a sideways button during an emergency... That's the point... Poor design decision...


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## Ed Woodrick (May 26, 2018)

NYer said:


> Right... It will have stopped due to the crash before regen does the job or before anyone reaches for a sideways button during an emergency... That's the point... Poor design decision...


Yes, I've driven in CA HOV lanes. Yes, I know the issues.

If slam the brakes, realized they and regen have failed (yes brakes use regen as well), and then reach to grab the handbrake and pull it. Then you may want to reevaluate your following distance. And how you use the brakes.
A) The probability of the brakes FAILING is probably 0% (yes, it could still happen)
B) If this is a big issue for you then you may want to reevaluate your braking, as it seems that your use it causing a high failure rate.
C) You definitely want t reevaluate your following distance, as you are not meeting the safe following distance.

Honestly, most people are going to take way too long just determining that the brakes have failed. Slam them, try again once or twice, and then move to the backup solution. You've probably already hit the car. But I assume that you have insurance and that the Tesla engage its safety features and bring you to a survivable stop (including when you are probably hit by the car behind you) and you get a new car out of it.;

As any Judge will tell you, if you can't stop in time if the car in front of you stops, then you need to back off.


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## NYer (Dec 11, 2018)

Ed Woodrick said:


> Yes, I've driven in CA HOV lanes. Yes, I know the issues.
> 
> If slam the brakes, realized they and regen have failed (yes brakes use regen as well), and then reach to grab the handbrake and pull it. Then you may want to reevaluate your following distance. And how you use the brakes.
> A) The probability of the brakes FAILING is probably 0% (yes, it could still happen)
> ...


Completely agree in the scenario of tail gating, which I don't do. It's more about going 65 MPH in HOV, someone from lane 2 jumps in without signaling/looking. Happens all the time in CA. Agreed - brakes rarely fail. This is just in the extremely rare case of a braking emergency and primary brake failure. Regen won't cut it.


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## JWardell (May 9, 2016)

Brakes are designed both very simply and with multiple redundancies to NOT fail. Where have you ever known brakes to completely mechanically fail, especially on a car with disc brakes?

Meanwhile the *handbrake* we used to have in the center of the car was barely enough to slow the car a bit and hold it on a hill, it is many times weaker than the hydraulic system or even the mechanical foot pedal, and uses just the rear half of the same actual brakes! I have known handbrakes to fail quite often.

The electronic parking brake in a model 3 presses the rear brakes with MUCH more force (especially if you hold it in a second time) than the old hand brake. ANd older teslas, the EPB activates an independent second set of pads.

And it's all pointless because unlike old cars with a handbrake, teslas slow themselves to a stop without the need for brakes in the first place.


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