Model 3 brake system is not responding causing bumper-to-bumper accident slow speed

[electrikar]

I would like to know if anyone has a similar experience as what I had with my first version of Model 3 (Long-range - Rear Wheel Drive - Tesla).

Please let me know if you have a similar experience; I did try to bring it back to the Tesla service center in Carlsbad, CA, and they said they could not find any issue. They said they are escalating the issue to the Tesla safety engineer in Fremont, CA and We have not heard back from them. They did ask me about the time/date and GPS location.

Here are the steps that I have experienced:

1. Trying to merge to the left lane ( one of the two left lanes)
2. Because of the traffic ( car in front of )- I could not merge, and I was asking people to let me merge in
3. I can merge only half of the car to the left lane
4. I am in the middle of two-lane ( the divider line is in front of me - the car may try to change / correct to the correct lane )
5. My car is getting close (moving) to the car in from of me - really slow speed
6. I am trying to push the break paddle - the break pad got tight up and did not respond to my force of pressing the paddle
7. the car keep moving and hit the car in front of me
8. when the light is green and the car in front of me was moving. My car was operated normally. However, it did hit another car in this front of me. It was a minor.


My Model 3 Spec:

Rear Wheel Drive 18’’
Aero Wheels -
Full Self-Driving Capability
Long Range Battery
Premium Upgrades Enhanced Autopilot

 

[Radlaw]

Were you in Autopilot?

 

[electrikar]

Were you in Autopilot?

no... - I just had a left light signal light on the camera was on

 

[Dangerous Fish]

Did you check to see if there was a brick under your brake pedal?

 

[buckets0fun]

Driver error.

 

[XPsionic]

What's a break paddle?

If you meant brake pedal, it's a completely hydraulic system and it's overall very reliable and effective.

The modes of failure for the lack of braking force, but yet feeling a firm pedal are few...

1. Mistakenly applied accelerator pedal pressure instead of brake pressure, with object aware acceleration turned on
2. Brake calipers are seized due to lack of maintenance of guide pins and lack of use
3. Brake rotors corroded/pitted due to age and lack of use
4. Brake pads not making good contact with rotor due to debris
5. There's a huge amount of air in the hydraulic system and the brake pedal simply sinks right to the end of travel and doesn't actually brake (highly unlikely)

From your description of events, it sounds like an extremely slow speed event, and even a half functioning hydraulic brake system will have no issues stopping a car from like 10mph basically immediately.

So my questions to you is, what does the brake system feel like when you use/test it during hard braking? What are the conditions of the components? And is it possible that you mistakenly pressed the accelerator instead during your "crash"?

 

[afadeev]

6. I am trying to push the break paddle - the break pad got tight up and did not respond to my force of pressing the paddle

What does "got tight up" means?
I can NOT think of any scenario or reason why a properly directed downward force onto the brake pedal would not result in vehicle deceleration.

a

 

[Radlaw]

no... - I just had a left light signal light on the camera was on

You were expected to be in full control of the vehicle. Just because you had the blinker on doesn't mean you can change the lane. It's just like any other car.

 

[RandyS]

When my 2018 Model 3 Performance was new, I had one incident when leaving home (on a slight downhill) where I discovered suddenly that the power brakes were not working. It caught me by surprise as I tried to use the brakes to slow down while going down the hill. If something would have been in front of me, I probably would have hit it because the overall feel was "No brakes", but I pushed VERY hard and got the car to slow down a little bit. So, yes, basic braking was working but the pressure on the pedal was something like 100x to get anything out of it.

I turned around in the next intersection and went back up to home and parked the car at the curb in front of my house ( and there was still no power brake action). I turned the issue into service and they went over the car remotely. They didn't really tell me much of anything but had me try the car again later and the brakes were working okay at that point. Still not sure what happened, but it never happened again...

So I know the feeling, OP. My first reaction was that the brakes were not working, but I really pressed about as hard as I could and was able to get a little bit of slowing. Could have been a scary situation if it would have occurred later in my drive at higher speed.

 

[XPsionic]

When my 2018 Model 3 Performance was new, I had one incident when leaving home (on a slight downhill) where I discovered suddenly that the power brakes were not working. It caught me by surprise as I tried to use the brakes to slow down while going down the hill. If something would have been in front of me, I probably would have hit it because the overall feel was "No brakes", but I pushed VERY hard and got the car to slow down a little bit. So, yes, basic braking was working but the pressure on the pedal was something like 100x to get anything out of it.

I turned around in the next intersection and went back up to home and parked the car at the curb in front of my house ( and there was still no power brake action). I turned the issue into service and they went over the car remotely. They didn't really tell me much of anything but had me try the car again later and the brakes were working okay at that point. Still not sure what happened, but it never happened again...

So I know the feeling, OP. My first reaction was that the brakes were not working, but I really pressed about as hard as I could and was able to get a little bit of slowing. Could have been a scary situation if it would have occurred later in my drive at higher speed.

Sounds like a brake booster issue. That's how brakes could feel when vacuum assist is lost

 

[Dan D.]

What's a break paddle?

If you meant brake pedal, it's a completely hydraulic system and it's overall very reliable and effective.

I dunno, if we're allowing people to call the accelerator a 'go pedal' then the other one may as well be the 'taking a break' pedal. And modern drivers have less understanding of mechanics, so since there are paddle shifters for the hands so why not paddles for the feet. Thus break paddles.

There. I did it! Anyway we know what was meant. Go pedal, break paddle.

 

[KenC]

I would like to know if anyone has a similar experience as what I had with my first version of Model 3 (Long-range - Rear Wheel Drive - Tesla).

Please let me know if you have a similar experience; I did try to bring it back to the Tesla service center in Carlsbad, CA, and they said they could not find any issue. They said they are escalating the issue to the Tesla safety engineer in Fremont, CA and We have not heard back from them. They did ask me about the time/date and GPS location.

Here are the steps that I have experienced:

1. Trying to merge to the left lane ( one of the two left lanes)
2. Because of the traffic ( car in front of )- I could not merge, and I was asking people to let me merge in
3. I can merge only half of the car to the left lane
4. I am in the middle of two-lane ( the divider line is in front of me - the car may try to change / correct to the correct lane )
5. My car is getting close (moving) to the car in from of me - really slow speed
6. I am trying to push the break paddle - the break pad got tight up and did not respond to my force of pressing the paddle
7. the car keep moving and hit the car in front of me
8. when the light is green and the car in front of me was moving. My car was operated normally. However, it did hit another car in this front of me. It was a minor.


My Model 3 Spec:

Rear Wheel Drive 18’’
Aero Wheels -
Full Self-Driving Capability
Long Range Battery
Premium Upgrades Enhanced Autopilot

Odd. If the brake pedal lit up, as you say, in 6, how would you know? Were you looking at your display?

Honestly, this sounds like a situation where you pressed the accelerator and not the brake, while under AP.

 

[Dan D.]

Odd. If the brake pedal lit up, as you say, in 6, how would you know? Were you looking at your display?

Honestly, this sounds like a situation where you pressed the accelerator and not the brake, while under AP.

He said it wasn't on AP and you may have misread #6 as he said "tight" not "light".

 

[jjrandorin]

I mean no disrespect at all by saying this, either overt or implied, if the following statement is not true.... but when I read the OPs post, my first thought was that it was likely written by someone for whom english is not their mother tongue so we likely need to cut them some slack and infer meaning.

 

[yeahthatguy]

I do believe there is a possible ABS/brake modulation issue that folks may not be giving enough attention to. I have posted about this on here, and gotten feedback on the various tesla subreddits.

I experience the scenario multiple times a week in all weather conditions after swapping on my winter tires (Hakka R5's) where when applying more force than usual to the brake pedal (not standing the brakes by any means but not a leisurely braking event either) the brakes the will engage, then release slightly before reengaging to complete the stop. This does not change the pedal feel (does not go limp/to the floor, is not spongy, etc) but you can 100% feel the temporary increase in momentum before the brakes reengage. This makes the stopping experience have an elastic feel to it. The first few times it caused me a bit of concern as I was unsure when the brakes would reengage fully, however now that I experience it once to twice a week I've learned the time/distance it takes for them to reengage and its only a minor annoyance.

My belief is this is ABS assuming the tires are slipping more significantly, when in actuality its a softer winter compound that the ABS is not happy with. I have gone through and reset the learned wheel details on the car a few times to see if this would help and it has not appeared to. I have put roughly 2,500 miles on the Hakka's since I put them on, which one would assume is more than enough for both the car to calibrate and for the compound in contact with the road surface to be free of manufacturing/install grime.

I run the MPP brake booster brace (and have since the car was new) I routinely check the rotors and have done the brake burnishing process in the service menu. I do not believe this is a hardware issue. I have considered getting a draggy or one of the CANbus monitoring tools to see if I can successfully record a change in G force during these events but I'm also a month or so out from swapping back on some high performance summer tires which very well could alleviate the issue.

 

[gtg465x]

What stopping mode was the car in? I'm guessing creep or roll, not hold?

 

[KenC]

I do believe there is a possible ABS/brake modulation issue that folks may not be giving enough attention to. I have posted about this on here, and gotten feedback on the various tesla subreddits.

I experience the scenario multiple times a week in all weather conditions after swapping on my winter tires (Hakka R5's) where when applying more force than usual to the brake pedal (not standing the brakes by any means but not a leisurely braking event either) the brakes the will engage, then release slightly before reengaging to complete the stop. This does not change the pedal feel (does not go limp/to the floor, is not spongy, etc) but you can 100% feel the temporary increase in momentum before the brakes reengage. This makes the stopping experience have an elastic feel to it. The first few times it caused me a bit of concern as I was unsure when the brakes would reengage fully, however now that I experience it once to twice a week I've learned the time/distance it takes for them to reengage and its only a minor annoyance.

My belief is this is ABS assuming the tires are slipping more significantly, when in actuality its a softer winter compound that the ABS is not happy with. I have gone through and reset the learned wheel details on the car a few times to see if this would help and it has not appeared to. I have put roughly 2,500 miles on the Hakka's since I put them on, which one would assume is more than enough for both the car to calibrate and for the compound in contact with the road surface to be free of manufacturing/install grime.

I run the MPP brake booster brace (and have since the car was new) I routinely check the rotors and have done the brake burnishing process in the service menu. I do not believe this is a hardware issue. I have considered getting a draggy or one of the CANbus monitoring tools to see if I can successfully record a change in G force during these events but I'm also a month or so out from swapping back on some high performance summer tires which very well could alleviate the issue.

Interesting. Are you sure that has nothing to do with the "blended" brake feature? I've had that brake feeling before when I had a Chevy Volt, but never in my Tesla.

 

[Dangerous Fish]

I do believe there is a possible ABS/brake modulation issue that folks may not be giving enough attention to. I have posted about this on here, and gotten feedback on the various tesla subreddits.

I experience the scenario multiple times a week in all weather conditions after swapping on my winter tires (Hakka R5's) where when applying more force than usual to the brake pedal (not standing the brakes by any means but not a leisurely braking event either) the brakes the will engage, then release slightly before reengaging to complete the stop. This does not change the pedal feel (does not go limp/to the floor, is not spongy, etc) but you can 100% feel the temporary increase in momentum before the brakes reengage. This makes the stopping experience have an elastic feel to it. The first few times it caused me a bit of concern as I was unsure when the brakes would reengage fully, however now that I experience it once to twice a week I've learned the time/distance it takes for them to reengage and its only a minor annoyance.

My belief is this is ABS assuming the tires are slipping more significantly, when in actuality its a softer winter compound that the ABS is not happy with. I have gone through and reset the learned wheel details on the car a few times to see if this would help and it has not appeared to. I have put roughly 2,500 miles on the Hakka's since I put them on, which one would assume is more than enough for both the car to calibrate and for the compound in contact with the road surface to be free of manufacturing/install grime.

I run the MPP brake booster brace (and have since the car was new) I routinely check the rotors and have done the brake burnishing process in the service menu. I do not believe this is a hardware issue. I have considered getting a draggy or one of the CANbus monitoring tools to see if I can successfully record a change in G force during these events but I'm also a month or so out from swapping back on some high performance summer tires which very well could alleviate the issue.

The ABS doesn't know or care what tyres you have fitted. What you are describing is normal and I have experienced it too, especially with winter tyres.
What the OP is describing is not something I have ever experienced or can explain, but they haven't given us enough context (road conditions, actual speeds, state of tyres etc.) and the general tone of the post suggests trolling to me.

 

[yeahthatguy]

Interesting. Are you sure that has nothing to do with the "blended" brake feature? I've had that brake feeling before when I had a Chevy Volt, but never in my Tesla.

Yes, I have checked into that possibility a few times and this feature has never been turned on for my profile. I'm not a big "one pedal" driver, I like to use my brakes.

The ABS doesn't know or care what tyres you have fitted. What you are describing is normal and I have experienced it too, especially with winter tyres.
What the OP is describing is not something I have ever experienced or can explain, but they haven't given us enough context (road conditions, actual speeds, state of tyres etc.) and the general tone of the post suggests trolling to me.

There is in fact a setting in the menu to select both the diameter and the compound (standard or winter), Tesla is mum on the specific details but it is a recommended "maintenance" item in the manual:

So there IS some mechanism for determining the tire compound's possible affects on braking performance. What specifically it does (if anything) is a mystery.

Now that all said, I do believe its the winter tires, and it does not sound like what the OP was describing, but I could see if causing alarm if you've never experienced it, add in too short of a stopping distance and I'd bet there would be issues.

 

[Dangerous Fish]

Yes, I have checked into that possibility a few times and this feature has never been turned on for my profile. I'm not a big "one pedal" driver, I like to use my brakes.



There is in fact a setting in the menu to select both the diameter and the compound (standard or winter), Tesla is mum on the specific details but it is a recommended "maintenance" item in the manual:

View attachment 904849

So there IS some mechanism for determining the tire compounds affects on braking performance. What specifically it does (if anything) is a mystery.

Now that all said, I do believe its the winter tires, and it does not sound like what the OP was describing, but I could see if causing alarm if you've never experienced it, add in too short of a stopping distance and I'd bet there would be issues.

No, there isn't, you are assuming that's why the wheel/tyre configurator is there. It makes no difference to braking or ABS operation.