I was driving 45 - 50 today in the left lane passing a very large truck, when he suddenly moved into my lane, either he did not see me or was pre-occupied. In any case i hit the brakes hard to fall behind him and the wheels locked and I skidded. It felt like the back is what locked up but I can't be sure. Has anyone else had the wheels lock up?
-
Want to remove ads? Register an account and login to see fewer ads, and become a Supporting Member to remove almost all ads.
I thought we had antilock brakes
- Thread starter Nikola M3
- Start date
Daniel in SD
(supervised)
That seems bad. Have you tried to use them again? If the problem is repeatable it should be easy to diagnose. Make sure no one is behind you!
Maybe this whole updating the ABS through a SW update wasn't such a good idea afterall. 
richrootes
Member
Daniel in SD
(supervised)
This is a lot better than the other possible failure mode!Maybe this whole updating the ABS through a SW update wasn't such a good idea afterall.
This does bring up a good experiment for us to do.
We know ABS is designed to prevent full lock up, but does that mean that it's not possible to lay some tread down while braking?
ABS has been around for a long time, but I constantly see brake trails like this. So what causes it?
Is it because it pulses so quickly that you're still going to get some tread laying down, and you visually can't see where it releases?
We know ABS is designed to prevent full lock up, but does that mean that it's not possible to lay some tread down while braking?
ABS has been around for a long time, but I constantly see brake trails like this. So what causes it?
Is it because it pulses so quickly that you're still going to get some tread laying down, and you visually can't see where it releases?
Daniel in SD
(supervised)
I think there are still a lot of cars and trucks out there without ABS. I drive one
.
Yes, the Model 3 certainly has ABS. Haven't needed to do a full panic stop but have had the ABS kick in when one wheel hit a patch of gravel.
What is with the burn out picture in the right lane?
After it slid I wanted evidence to show the SC, I went back and took this photo of where the tires locked. Not a burn out.
I had this happen last week but I had hit the brakes when in I went into (sand on pavement) on the side of the road, That time it also slid but I had discounted it because of the surface.
Today was a real panic stop on hard surface. I did not feel a pulse but it did stay straight.
I will report back when I get some feedback from the service center.
I think that was probably Traction Control or Dynamic Stability Control where momentary brake application is performed on individual wheels. To really notice the benefits of ABS you need to do a panic stop and the key benefit being the wheels should not lock up.
Daniel in SD
(supervised)
You don't have to panic though, just press hard on the brakes and the ABS will activate
If the wheels lock up, there's a loud screeching noise and there's a lot of smoke your ABS is broken and you've probably flat spotted your tires. If the ABS is working you will feel a pulsation in the pedal and hear the solenoids modulating the brake pressure to all the wheels.
If the wheels lock up, there's a loud screeching noise and there's a lot of smoke your ABS is broken and you've probably flat spotted your tires. If the ABS is working you will feel a pulsation in the pedal and hear the solenoids modulating the brake pressure to all the wheels.
You don't have to panic though, just press hard on the brakes and the ABS will activate
If the wheels lock up, there's a loud screeching noise and there's a lot of smoke your ABS is broken and you've probably flat spotted your tires. If the ABS is working you will feel a pulsation in the pedal and hear the solenoids modulating the brake pressure to all the wheels.
So if you don't feel the solenoids, then you panic?
Daniel in SD
(supervised)
Haha. Then you let off the brakes so you don't flat spot your tires. If your OTA firmware update failed and your solenoids are stuck open, disabling your brakes, then you panicSo if you don't feel the solenoids, then you panic?
silentsnow31802
Member
Wait... if you were in the left lane why are the marks in the right lane?
Also those do seem like acceleration marks to me. They are dark at the start and get lighter as they go on.
Also those do seem like acceleration marks to me. They are dark at the start and get lighter as they go on.
JohnSnowNW
Active Member
Are Tire Marks Still Useful with ABS Systems? - CED BLOG
Granted the beginning of the skid marks are darker than the above description seems to imply, but the idea that ABS equipped vehicles do not leave skid marks is incorrect.
Daniel in SD
(supervised)
The static friction (sticking) of a tire is a little bit higher than the dynamic friction (sliding) so the ABS system try to keep all the tires right on the verge of locking up. A properly functioning ABS system should not lock up any of the wheels. Maybe some of the older system did? But all modern ABS systems are 4-channel so that they can control braking to all the wheels.
ABS leaves very faint marks and you should also see the pulsation in the mark. When you use ABS you can hear that it is skidding a little bit it sounds nothing like fully locked brakes. The marks in the picture do acceleration to me or maybe braking in the opposite direction coming to a full stop. I'm not an accident reconstruction expert though...
