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Brake failure on brand new MYP?

MY-Y

Active Member
Mar 4, 2020
1,492
1,816
MD
Let state my theory more emphatically. If you have new brakes and haven't bedded in the pads, expect a surprise when you try to stop hard. New brakes, and consequently, a new car needs to bed in the brakes. On an ICE car, they'll bed in naturally after a several trips (though you should intentionally bed them and not wait for it to happen with regular driving). On a Tesla with strong regen brakes, it could take months for the brakes to bed in properly. The result is much longer braking distances when braking hard. Unfortunately, the brakes will feel pretty normal when used lightly.
 

H4V0C

MYP MSM|Blk Mar 8 DD
Jan 16, 2022
37
45
Tampa, FL
Can we see the dashcam video?
Sure. I'll put the first 10sec on YouTube but you'll have to go to my OnlyFans account to see the rest.

Just guessing here, but depending on ambient temps, overnight rust on the rotors, temp of the brakes at the time, and (hard?) performance brake pads, there might not have been much bite in the brakes.

I'm also wondering about the distances you're remembering, and how little time you had to react might indicate how close you actually were prior to engaging the brakes and the ultimate crash.

The laws of physics win every time.
It was about 73 degrees, no rust on the rotors (garage kept). Brakes definitely weren't warm, 99.9% of the time I just regen to brake. It's hard to gauge from the video, but as I was hitting the brakes, I was sure I had plenty of time/room to stop...when they didn't grab, I knew I was fuxored.

OP I am going to give you the same caution that I give others when someone asks this question. There is little that TMC members seem to enjoy more, than "digging in" to a video of a crash here, dissecting it frame by frame, and saying things like "if you look at 45 seconds into the video and pause it, you can clearly see......"

You have absolutely NOTHING to gain from posting this video, other than the potential acceptance of your position by a bunch of internet strangers. What you have to lose, however, is what many times turns into a proverbial "witch hunt", that will last long past this thread.

TL ; DR ... I advise that you dont post any video, but of course thats up to you.
Thanks for the heads up. I'm sure some people will clown me but it's all good. If someone feels good about putting me down then I'm glad I could make their day.

This is why I use my brakes hard at least once a week. With the regen on high you really don’t use the brakes and they could have build up on the rotors and pads. When you try to panic stop it won’t. Every time I wash my car the next day I go and do 3 moderates stops and by the 4th she stops very well. Sorry to hear this and hope I’m wrong. But this is my opinion.

as far as the collision avoidance system I keep mine off I had it try to pull me into another lane on a two-lane highway after it told me I was going to go off road sometimes this car is not smarter than the driver. I do use auto pilot in traffic but that’s pretty much it again sorry to hear about your brand new model Y hope it works out for you. If you plan on getting a lawyer I would not post your dash cam video.
I'm no gearhead but if what you're saying is true, that could very well be part of my problem. I can't say I've never used the brakes, but I rely on the regen braking most of the time so I've probably never applied more than 25% brake before the crash. Thanks for the well wishes!

Hmm I don’t think this is a failure of the brake booster master cylinder or the backup hydraulic compensator… usually when those go bad your brake pedal gets really stiff. Your problem is the pedal goes all the way through without resistance.
Brake pedal didn't feel stiff, didn't feel like there was zero resistance either though. Pedal felt normal, just felt like the pads never grabbed.

I wonder if somehow you blew through your brake bleeder screws? so losing one pair of brakes should leave you with pressure on the other pair. 4 wheel brake failures are super uncommon in vehicles with all this redundancy.
Not sure but after reading some of the other replies, I'm thinking my failure to bed the brakes probably has more to do with the crash.

If you never bedded your brakes, they won't be at peak performance.
I definitely never did that :( maybe I'm naive but I didn't even know that was a thing.

Were you charged to 100% when this happened?
I would have been around 70-75%. I charged to 95% the night before and the crash happened after driving 73 miles, most of that on the highway.
 

H4V0C

MYP MSM|Blk Mar 8 DD
Jan 16, 2022
37
45
Tampa, FL
Be careful OP, there is consequence if you fight with Tesla and its fanboys

I'm not looking to fight anyone, was just asking for advice. I definitely get the feeling that there are some fanboys on here fighting me, doesn't bother me though, I get understand and appreciate their passion for the company. I'm not trying to trash the name, just stating my perspective to the best of my recollection and looking for insights from people with more experience. If I'm wrong, I have no problem apologizing, you wouldn't have to force that out of me.

Let state my theory more emphatically. If you have new brakes and haven't bedded in the pads, expect a surprise when you try to stop hard. New brakes, and consequently, a new car needs to bed in the brakes. On an ICE car, they'll bed in naturally after a several trips (though you should intentionally bed them and not wait for it to happen with regular driving). On a Tesla with strong regen brakes, it could take months for the brakes to bed in properly. The result is much longer braking distances when braking hard. Unfortunately, the brakes will feel pretty normal when used lightly.
Man, this really sounds like a big part of my issue. With 700 miles on the car and only using light braking on very rare occasions, my rotors were probably pristine. Wonder if I can get someone at the collision center to send me some pics, I'm definitely curious.
 

Pianewman

2021 MYLR VIN 88,XXX, Rd/Wh, 12/20 delivery
Supporting Member
Oct 28, 2020
2,688
2,434
Fort Worth
I just now remembered having a similar "WTF" moment with braking early on in my MY experience. Like several here, I use regen almost exclusively, but I've started getting on the brakes more energetically. H4VOC's experience reminds me to do it more often. It's easy to do, as I'll charge to 100% every 2-3 weeks, and brake the car vigorously. Doing this has also cut down on the morning brake squeal while reversing out of my driveway.
 

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