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Musk Says Model 3 Brakes Need Work, Firmware Update Coming in a ‘Few Days’

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Responding to Consumer Reports’ criticism of the Model 3’s braking ability, Tesla CEO Elon Musk tweeted Monday that the company will “make sure all Model 3’s having amazing braking ability at no expense to customers.”

Consumer Reports said the Model 3’s stopping distance of 152 feet from 60 mph was far worse than any contemporary car they have tested. Musk called their results “strange” and inconsistent with other reviews. He suggested that performance may vary by vehicle and Consumer Reports may have had their hands on a dud.


Musk later tweeted that braking tweaks can be made through a firmware update, which Tesla intends to ship in a few days. He said the company is dedicated to making the Model 3’s braking better than any comparable car.

Consumer Reports also said the Model 3’s stiff ride, unsupportive rear seat and excessive wind noise at highway speeds hurt its road-test score. Musk said the magazine was testing an early production car and those issues have since been addressed for cars coming off the assembly line today.


Tesla has acknowledged that the Model 3’s braking needs improvement. The good news is that the company can seemingly avoid an expensive recall and make those performance improvements via a software update.

 
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Elon,
Besides the software you may want to check the brake pads. I have had experience with hard long lasting brake pads which degrade the braking performance substantially.compared to the brake pads optimized for braking performance. As far as ride is concerned you may wan to offer an option, BMW M-3 or 325 like ride for performance enthusiast and Avalon like ride for people like me who don't go around corners very fast and desire a comfortable ultra smooth ride. Many people buy cars based on these two criterion. Just my 2 cents
 
Too bad you haven't learned how to read before you learned how to troll posts.. What he said was the car they tested was an early production vehicle and those nonfirmware adjustments were addressed and that he would request CR retest with a current vehicle. I know that having and using facts is terribly inconvenient when you don't care about reality and only want to perpetuate your personal agenda. Too bad! You lose again and reveal your incompetence at the same time. Thanks i enjoyed being able to laugh at this post

I hope CR doesn't accept a brand new car from Tesla to test. Once the fix is available and applied, the same car(s) should be tested to see if the fix actually took care of the braking problem.
 
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I hope CR doesn't accept a brand new car from Tesla to test. Once the fix is available and applied, the same car(s) should be tested to see if the fix actually took care of the braking problem.
You are mixing up to elements lol - Braking was a firmware update - rest is about early production car and those changes of course wont happen based on over the air update
 
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My experience with Consumer Reports has been relatively good. Toyota Camry was rated as the most reliable car when I bought it and I ended up never having any issues with it other than the plastic door handles breaking which they fixed in the newer versions. I put 250,000 miles on the car so Consumer reports saved me a lot of money. A Lot of their criticism are based on driving so many other cars so they often have some merit. I know nothing about the Model 3 but I can tell you that Consumer reports reviews of other cars are often quite accurate. They are not biased by performance or other things that are typically not important to the average consumer. That is what Car and Driver is for.
 
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If the ABS software was not programmed correctly, and OTA update can theoretically fix that. If it's purely a software issue. Seems like Elon doesn't know if it is just a software issue though.

I am not sure they can push an update to the ABS controller OTA. Usually the ABS controller is a separate and distinct controller (for obvious reasons). I think it is more likely they can push an update to regen during hard braking. If compromises were made on pad performance for longevity (less wear, worse peak performance), it's possible they were made with an assumption that regen would fill the performance gap - something an ICE car can't do. If regen isn't working on some cars as it should, that would explain a lot.

This is pure speculation.
 
I am not sure they can push an update to the ABS controller OTA. Usually the ABS controller is a separate and distinct controller (for obvious reasons). I think it is more likely they can push an update to regen during hard braking. If compromises were made on pad performance for longevity (less wear, worse peak performance), it's possible they were made with an assumption that regen would fill the performance gap - something an ICE car can't do. If regen isn't working on some cars as it should, that would explain a lot.

This is pure speculation.

Anything with a communication bus (or even a single IO line) can be updated (assuming it was programmed to allow it).
It has to be (at least partially) an ABS update since the ABS system should allow maximum braking authority (up to wheel lock up) without the assistance of regen (case in point: full or cold pack with zero regen).
 
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Anything with a communication bus (or even a single IO line) can be updated (assuming it was programmed to allow it).
It has to be (at least partially) an ABS update since the ABS system should allow maximum braking authority (up to wheel lock up) without the assistance of regen (case in point: full or cold pack with zero regen).

Still not sure I'd believe ABS OTA updates are a capability. Seems ... risky. But, I understand your point and recognize that it's very possible.

Just to clarify my point - if ABS is tuned out of the box to work a certain way with regen (as it would have to as you point out with full/cold pack) and in fact regen was not holding up its part of the bargain, then that's something that could theoretically be fixed OTA.

That said, you bring up an interesting case - should a brake test in a Tesla be done with a full or cold pack so regen is off/diminished, or under more typical circumstances where regen can contribute significantly? And if you're Tesla would you dare optimize your braking system assuming regen is available when there are uncommon but not atypical situations where regen might be unavailable entirely??
 
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Still not sure I'd believe ABS OTA updates are a capability. Seems ... risky. But, I understand your point and recognize that it's very possible.

Just to clarify my point - if ABS is tuned out of the box to work a certain way with regen (as it would have to as you point out with full/cold pack) and in fact regen was not holding up its part of the bargain, then that's something that could theoretically be fixed OTA.

That said, you bring up an interesting case - should a brake test in a Tesla be done with a full or cold pack so regen is off/diminished, or under more typical circumstances where regen can contribute significantly? And if you're Tesla would you dare optimize your braking system assuming regen is available when there are uncommon but not atypical situations where regen might be unavailable entirely??

ABS at the basic level only kicks on when a wheel locks up. Up until that point the braking force is 100% based on the driver pedal pressure * booster assist. If you want to brake harder you push harder, so any fixed offset due to assumed regen can be bypassed by pushing harder.

Where it gets funky is if the ABS system anticipates the force need to lock up a wheel. If (made up number) 15kPa locked the wheels the last two braking events, maybe it starts backing off at 14kPa. If that were the setup, then the extra torque of regen would be a critical factor in the calculation (how much regen during the two lock up events vs how much now).
This type of system would be great in adverse conditions due to ability to reduce the number of lock up events and thus reduce stopping distance. The downside being if it 'learns' wrongly and overly reduces maximum braking, then you end up taking longer to stop.
 
ABS at the basic level only kicks on when a wheel locks up. Up until that point the braking force is 100% based on the driver pedal pressure * booster assist. If you want to brake harder you push harder, so any fixed offset due to assumed regen can be bypassed by pushing harder.

Where it gets funky is if the ABS system anticipates the force need to lock up a wheel. If (made up number) 15kPa locked the wheels the last two braking events, maybe it starts backing off at 14kPa. If that were the setup, then the extra torque of regen would be a critical factor in the calculation (how much regen during the two lock up events vs how much now).
This type of system would be great in adverse conditions due to ability to reduce the number of lock up events and thus reduce stopping distance. The downside being if it 'learns' wrongly and overly reduces maximum braking, then you end up taking longer to stop.
We need an ABS expert here! That's not me but you can't do what you're describing because on the first stop you could be stopping on a wet surface and then the next stop you could stopping on a dry surface. The problem with any sort of self calibration is that most people don't drive around using the ABS very often. I've met people who have never used the ABS on their cars!
It always feels to me like ABS is letting the wheels slip a little bit and then letting off the brake pressure. I don't think it's possible to predict how much traction the road surface has without actually getting slippage. I suppose the regen could confuse the ABS controller if it's also modulating the rear "braking" force. That would be a control system nightmare! It would be interesting to see if the same inconsistency in braking distance is seen with the regen off.
 
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We need an ABS expert here! That's not me

True dat, not me either.

ABS usually works the way you mention.

I agree the 'less that I think is possible' braking force method has issues. I'm probably over extrapolating from the "ABS calibration algorithm" tweet.

Maybe the issue is in the slip detection routine? It starts seeing lock up when there isn't any?

I think regen kicks off on lock up. At that point, ABS has to drop pressure anyway to go from slip to rolling traction and then ABS continues as normal (as long as regen stays off).
 
An important point for Tesla to consider:
For Consumer Reports suspension or ride criticisms that Elon addressed in addition to the braking performance, the issue is whether the Model 3 suspension is tuned or designed for a BMW like ride where you feel the bumps but can corner very well or a Avalon like ride where you don't feel the bumps and but cornering is compromised. Since I don't go around corners very fast, I prefer the Avalon ride. Toyota sells a lot more cars than BMW so I would think that if Tesla is interested in maximizing sales they would offer both suspension options. Not all drivers have a the same perspective. Isn't that what it is all about-freedom of choice? Instead of Tesla focusing on performance people only, I suggest an optional suspension package with a ultra smooth suspension with sound dampening like that found in Avalon, most of the Toyota line including the Corolla and higher end Lexus cars since many of the average consumer prefer a smooth quiet car to cruise in.
 
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An important point for Tesla to consider:
For Consumer Reports suspension or ride criticisms that Elon addressed in addition to the braking performance, the issue is whether the Model 3 suspension is tuned or designed for a BMW like ride where you feel the bumps but can corner very well or a Avalon like ride where you don't feel the bumps and but cornering is compromised. Since I don't go around corners very fast, I prefer the Avalon ride.

@Peter Thomas Tesla already made their decision when they softened the suspension back in December, and then offer that as a retro-fit for anyone that got the overly stiff suspension that asks/complains about it. (From what I have read they split the difference between your examples to try to make the most number of people happy with a single suspension option.)
 
I hope CR doesn't accept a brand new car from Tesla to test. Once the fix is available and applied, the same car(s) should be tested to see if the fix actually took care of the braking problem.

@bro1999 Elon never offered to provide them a car for testing. All he said was "Also, Consumer Reports has an early production car. Model 3 now has improved ride comfort, lower wind noise & many other small improvements. Will request that they test current production."

In other words they know early production had issues, so how about you try to get a car more recently built to see how we are doing now instead of how we were doing almost a year ago.
 
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