Brakes temporarily not working!

[eggy]

Hi

After 8 months I experienced today the following for the 1st time.
After leaving my drive way, I had to stop after 400 feet at a crossing.
When I hit the brakes as usual to get to a stop, nothing happened!!! :scared::scared::scared:
Of course I was very surprised not saying terrified and instinctively hit the brakes as hard as I could, like for an emergency stop.
Luckily this helped and the car came to a stop. After this, braking was fine and back to normal when I continued my way.
Later on, having the car parked for about 15 min., I again took off and the same thing happened!
I will call SC tomorrow.
Anybody experienced something similar?

 

[MsElectric]

This sounds almost implausibly strange, especially because the Tesla brake system has a manual failsafe so your statement that brakes were not "working" can't be true so you might want to edit the subject of this thread.

The worst I can see happen is an issue with the electronic braking system but that should have caused an error to show up.

 

[eggy]

This sounds almost implausibly strange

I could repeat the same behaviour multiple times, why implausible?
No error message appeared.
Happy to change the title. How would you call it ?

 

[Super_Popular]

Hi

Hi!

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I could repeat the same behaviour multiple times

You really should have stopped driving your car if the brakes where not working.

Hopefully you have.

 

[MsElectric]

I could repeat the same behaviour multiple times, why implausible?
No error message appeared.
Happy to change the title. How would you call it ?

I felt it was strange that you saw no error messages for such a critical failure and given a worst case scenario, the brakes should still have worked, albeit with more manual force needed. The braking system is quite robust with a redundant manual backup system.

In any case if you are not sure about your brakes, please do not drive your car. Have Tesla flatbed it and figure out what caused it.

 

[Jhall118]

Was this in heavy rain, or completely dry? A few people in Seattle have experienced a delayed braking response that had a simple fix at the service center, but this only occurred in rainy weather.

Your case sounds a bit different though.

 

[sorka]

What did the brake pedal do? Was it soft? Did it go to the floor? Did it become firmer as you pressed the next time or pumped it? Have you checked the brake fluid level? Or was the pedal firm like usually is when things are normal but the car just seemed to not stop. Were the brakes wet? Was it raining?

 

[eggy]

Was this in heavy rain, or completely dry? A few people in Seattle have experienced a delayed braking response that had a simple fix at the service center, but this only occurred in rainy weather.

Your case sounds a bit different though.

Well, climate conditions as a source for the problem came to my mind too.
We got very humide and foggy conditions today. But I would have expected a delay while breaking like you sometimes experience after a car wash - but this is/was different. I'll keep you posted about my SC visit.

 

[CHG-ON]

I think having nothing happen under normal braking and saying brakes temporarily not working makes complete sense.

I hope it doesn't happen again for you.

 

[eloder]

My own EV won't have regenerative braking when the battery pack is near 100%, or when it is cold outside (anywhere near/below freezing). The brake behavior doesn't change though, so I need to press at least 25% before my brake pedal will do anything in both of those conditions. This doesn't sound too much like something normal, though.

 

[Electricfan]

Perfect thread title. Anything even remotely critical of Tesla will draw a crowd on this forum, you just have to get used to it. Lord knows I have!!! Anyway, thanks for posting and let us know what the SC says, as that's exactly what a forum like this is for! My brakes haven't ever done this, not on my 2013 or my 2015 car, just for reference, and I've never read about this particular symptom in a Model S before. Very interested in the resolution.

 

[Chris]

That sounds like the same issue I, and others, have had when braking in rain (see thread), especially since you have a classic P85. That was very real, despite some forum members claiming that we didn't know how to use the brakes. The SC back then replaced the discs with an upgraded version and I have not had any further problems. Good luck.

Braking in rain - Page 20

 

[thimel]

It sounds like your power brakes were not working. When this happens, one has to press the pedal VERY hard in order to stop. For a very short time about a year ago, there was a firmware bug which allowed the car to be put in drive before the power brake pressure had come up. A couple of people reported they had no brakes immediately after starting their car. Tesla fixed it very quickly. Definitely take it to the SC so they can fix it and let us know what caused the problem.

 

[harry]

Both our Model S are very early production models, and both on occasion do exactly what the OP described. One or the cars has had its rotors and pads replaced with a "cold weather package" (as described by the SC), which didn't fix the problem. It happens rarely, and only on the first attempt to brake after the car has been sitting overnight. With all the force we can muster on the pedal the car still just glides to a stop. We've learned to watch for it at the end of our driveway, and just live with it.

 

[Chrisizzle]

I've had incredibly weak braking performance where my foot goes quite literally to the floor and you can hear/feel the anti-locks let the wheels keep spinning. The second (and all subsequent) brake attempts are fine.

First two times this happened were upon pick up of the car from Tesla service and I didn't know what to think. It's happened three or four times since and always due to wetness. Brakes are useless after a car wash and occasionally after sitting outside in heavy rain. I now deliberately test the brakes every time it's damp out.

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Perfect thread title. Anything even remotely critical of Tesla will draw a crowd on this forum, you just have to get used to it. Lord knows I have!!!

Thread titles should be short summaries that help other forum users search and find topics of interest. Tesla publicity or promotion should not be a top priority. I found this title perfectly accurate and something I experienced.

To your point, even something politically correct like "Brake inconsistencies " would cause a Tesla hater to click, read and spin to their liking. Haters gonna hate.

 

[Cyclone]

This was a bug in one of the 6.1 or 6.2 releases. Hopefully this isn't a bug that reared its ugly head again and instead is an isolated issue to eggy's car.

 

[eggy]

Hi all
Thanks for all the views, hints and tips.
My wife was today @ the SC.
Today the situation was not reproducable anymore. It seems to have something to do with the climate conditions, since it was significant less humid than yesterday. At the SC, they did several checks, verified the logs but couldn't find anything.
The technican meant that this could happen theoretically and very rarely in very humid conditions, but it isn't a pattern that they have come across yet.
He suggested to make sure to push the brake pedal very hard in similar conditions before driving off.
I'm not very happy with this, but will keep on watching very closely and maybe the next time I'll be able to demonstrate to the SC.

Thanks again for your advice!

 

[Todd Burch]

Not sure what the OP's issue was specifically, but in general (not directed at anyone in particular) you should recognize that braking performance is dramatically reduced when the rotors are wet, which is completely normal. You'll encounter this if you've been driving in wet conditions for awhile without using the brakes. When you apply the brakes, the first few seconds you'll notice that braking action is significantly less than usual.

I assume most drivers know this, but from some of the posts above it seemed like some were not aware.

 

[Electricfan]

Not sure what the OP's issue was specifically, but in general (not directed at anyone in particular) you should recognize that braking performance is dramatically reduced when the rotors are wet, which is completely normal. You'll encounter this if you've been driving in wet conditions for awhile without using the brakes. When you apply the brakes, the first few seconds you'll notice that braking action is significantly less than usual.

I assume most drivers know this, but from some of the posts above it seemed like some were not aware.

Do you have a link to any place this is documented? I found some stuff about stopping distance increasing on wet roads, but that's because the road is wet, not the disc brakes. I'd be very interested to read something if you have it. Thanks.

http://www.drivingtesttips.biz/stopping-distances.html

 

[Todd Burch]

Do you have a link to any place this is documented? I found some stuff about stopping distance increasing on wet roads, but that's because the road is wet, not the disc brakes. I'd be very interested to read something if you have it. Thanks.

http://www.drivingtesttips.biz/stopping-distances.html

It's not in a specific manual that I'm aware of--it applies to all cars, and is just a simple result of physics: wet surfaces (brake rotor and pad) have a lower coefficient of friction (less braking force) than dry surfaces because the water fills in microscopic pockets in the surfaces, reducing the roughness and making it easier for the materials to slide along each other.

I have never driven a car that didn't have reduced braking effectiveness (at least for a few seconds) when the brakes were wet. It's true that old school drum brakes were far more affected by this than today's disc brakes, but the effect is still there.