Accident for unable to brake efficiently: Tesla's or my fault? [early 2020]

[AlanSubie4Life]

Looks like the car ahead of you brakes at 9 seconds. Based on the “dive” of the nose of your car, looks like you did not brake until 12 seconds, immediately after the light turned red.

At that point, presumably the traction provided by the tires was insufficient to stop the vehicle. It appears perhaps you eased off the brake as well (perhaps in response to the sliding), but hard to tell.

This accident was definitely your fault, due to inattention. You need to allow sufficient following distance in all conditions.

I would have expected that if FCW was set sensitive, you would have heard it alarm prior to application of the brakes, in this case. But there is no guarantee of that.

 

[GoodManFrank]

Looks like the car ahead of you brakes at 9 seconds. Based on the “dive” of the nose of your car, looks like you did not brake until 12 seconds, immediately after the light turned red.

At that point, presumably the traction provided by the tires was insufficient to stop the vehicle. It appears perhaps you eased off the brake as well (perhaps in response to the sliding), but hard to tell.

This accident was definitely your fault, due to inattention. You need to allow sufficient following distance in all conditions.

I would have expected that if FCW was set sensitive, you would have heard it alarm prior to application of the brakes, in this case. But there is no guarantee of that.

FCW didn't trigger.

This is an interesting discovery. There was indeed a dive of nose, or say bounce down of the view, around 11.5-12s, but I started braking way before that, with regen first. Maybe it's just a bump on the road, or maybe that's when I slammed the pedal hard when I realized regen won't stop the car in time.

 

[ALSETJC]

Yeah, I'd have to agree with most , rear ending someone means at fault most of the time no matter what occurs. What I do when I know I may need to possibly use the brakes is ride the brakes. You can feel when it is using friction brakes and not so I'm ready to apply slightly extra braking force as needed earlier without locking the brakes up. In winter with less Regen (I see you're from California so might only occur in early mornings), on red lights sometimes you have to apply bit of the brakes. Since you just got your car I know this is something that takes a bit of getting used to.

 

[GoodManFrank]

red light ,green light all the same. trololo.

Sorry I suck at English :-(

 

[Rowan256]

Can you repeat the brake not functioning well? I mean, I would at least steer the other way if I noticed my brakes don't work properly.

 

[qdeathstar]

Thanks everyone. Additional comments:

2. About the speed I was driving at, I was driving at the same speed as other cars before the light. Don't know the exact number unless Tesla tell me from the logs.

Hi, could you count how many cars you passed in the video for me?

 

[ElectricIAC]

This is why I drive like my friction brakes don’t exist 99% of the time, but then again, I hate energy waste when it doesn’t benefit me in time.

 

[Gorpis]

If you rear end someone from behind its your fault, not the cars fault. You passed the first 3 cars in the video and it looks like you were going faster than 35 mph, hard to tell but you know how fast you were going.

 

[MacGreiner]

I've said it multiple times throughout the forum that the M4MXs are by far the very performing tires I have had in the wet. From day 1, I never felt I could trust the car in the wet.

 

[ElectricIAC]

I've said it multiple times throughout the forum that the M4MXs are by far the very performing tires I have had in the wet. From day 1, I never felt I could trust the car in the wet.

Very performing?

 

[vickh]

They don't alarm and don't automatically intervene if you manually override them such as pressing on the accelerator, brake pedal, steering...

so AEB doesn't protect you from yourself.. I wonder if AP would have avoided this accident?

 

[vickh]

Very performing?

very worst performing?

 

[Dangerous Fish]

You had space to your right to steer onto that piece of road without risking hitting the car in front of you. This is exactly what ABS is for.
I'd suggest getting better tyres and going on a skid pan or defensive driving course to gain more awareness of what to do in similar situations.

Also, most drivers don't look far enough ahead or press the brake pedal hard enough when an emergency demands it.

I was running a driving course last week where we did just this sort of exercise - lane changes/obstacle aviodance. It takes most people a few tries before they are confident enough to properly use the ABS and safety systems the car provides, so you're not alone.

 

[YusufT]

Most people forget that you barely use your brakes in this car. I remember Tesla said to brake hard repetitively at least once a week to get the oil going and make sure it’s fine. I forgot to do this for a while. When I pushed the brake pedal hard it was very hard and took a second to catch on and really start slowing down. Especially if you’re on salty roads in the winter it’s even worse. I think you guys just need to ensure your brakes are in good condition instead of not using them for weeks/months and when I bash it in you complain it was just “coasting”

 

[Ol'Blue]

Looks like driving to fast (for the conditions at least). Everyone else was more cautious.

The road surface looked a bit choppy plus the wet conditions may have made for a longer necessary stopping distance.

If you slammed on the peddle you may have triggered the abs when it wasn’t totally needed under lighter breaking, resulting is a slightly less responsive peddle. Smooth application is always best.

the short stop distance you allowed was shortened by the driver in front stopping with a safe distance to the intersection.

can’t comment on why the warning systems didn’t intervene, but safety features are there to help only, and should never be relied on completely. You are responsible for your car, not the car.

 

[holmgang]

Thanks everyone. Additional comments:

1. I was paying full attention to the road, so please do not assume distracted driving. Thanks!

2. About the speed I was driving at, I was driving at the same speed as other cars before the light. Don't know the exact number unless Tesla tell me from the logs.

3. Yes it is a downhill because it's a bridge on the highway, but the slope is negligible when it comes to the traffic light.

Actually it's the reverse. In low-friction situations, a slight slope is all the difference in the world. This is often compounded by the fact that rises caused by bridges means less thermal mass, and thus moisture on bridges freeze much more easily.

In this particular location, conditions did not reach ice, but moisture (and especially oils) significantly reduced the grip, and that it's on a downslope just magnified everything. That's been my experience with hairy moments on the road.

Well, according to my experience, normal vehicle would be able to brake much more efficiently under that situation, especially the last few feet, where it was not slowing down at all.

"that situation" = in the dry.

This situation, the Tesla behaved exactly as a "normal vehicle". When you intially touched the brakes, the car slowed down some. In the last few feet you stomped harder, which MADE it exceed friction threshold, and thus it slowed down less (and triggered ABS system...)

So while the decel response was counter-intuitive to your expectations, it was exactly how it's supposed to happen, in any vehicle, governed by physics/

 

[blazeform]

Tesla has something of a diminished reputation when it comes to brakes, Elon even admitted there were problems back in 2018 when consumer reports found that the model 3 had the worst 60 to 0 braking delta of any car tested. I think it's to Elon's credit that he admitted to the issue instead of trying to excuse it, and vowed to make model 3 braking superior to all other vehicles, even if it meant hardware upgrades for the fleet. An OTA update was released and consumer reports reversed their stance, but here we are in 2020 and it appears that there are still some issues to be worked out (even others in this thread have reported similar experiences). The bottom line is the model 3 is still a work in progress and it's good to be wary of its weaknesses... Yes, braking shouldn't be one of them, but I'm sure Tesla is working hard to fix the issue because if the narrative around their brakes continues to worsen it could irrerepribly damage the brand.

 

[TMThree]

Looks to me like you skidded on the wet pavement. Why do you claim that the brakes didn't work as they were supposed to?

The stock 18" tires are garbage in wet conditions.

 

[Dangerous Fish]

Looks like driving to fast (for the conditions at least). Everyone else was more cautious.

The road surface looked a bit choppy plus the wet conditions may have made for a longer necessary stopping distance.

If you slammed on the peddle you may have triggered the abs when it wasn’t totally needed under lighter breaking, resulting is a slightly less responsive peddle. Smooth application is always best.

the short stop distance you allowed was shortened by the driver in front stopping with a safe distance to the intersection.

can’t comment on why the warning systems didn’t intervene, but safety features are there to help only, and should never be relied on completely. You are responsible for your car, not the car.

In this situation, the brakes were not to blame at all.
If you want to blame it on the car, blame it on the tyres, but the driver could have avoided the accident in any case.

 

[AlanSubie4Life]

Yes, braking shouldn't be one of them, but I'm sure Tesla is working hard to fix the issue because if the narrative around their brakes continues to worsen it could irrerepribly damage the brand.

Lol.