Traction control glitch?

Traction control glitch?

2015 S85D, ~49000 miles

I was driving from San Jose to Santa Cruz on highway 17. If you've done this drive you know how 'interesting' it can in a Tesla.

Coming downhill at high speed in the traffic flow I was under full regen ..the usual concrete barrier off to my left and car to the right....the left front tire 'shuddered' skidding but was fighting me. The traction control icon came on for a brief moment.

I held course and didn't hit the wall or the car to my right. In few minutes it happened again, in the same conditions.

Pavement dry as bone, no oil, no sand. Autopilot (AP1) NOT in use. (I'm not that crazy)

What was this? Did the side ultrasound sensors do this? (Perhaps a car too close to the right?)

I remembered the time for later and also did a 'bug report...traction control'. Should I just ignore this or should i make an appointment to have it checked out?

Bighorn | January 18, 2020

Lane departure warning? That road is tough at night keeping up with the locals who know its course.

Stiction | January 18, 2020

No sir, not lane departure. A real tugging/juddering.. And as I mentioned, the traction control active icon came
on at the same time. | January 18, 2020

Doubtfull anything wrong. Sounds like traction control activated due to uneven pavement undulations or something on the road you didn't actually see (sand/oil or such). Unless you stopped at the exact spot and examined the road - something that is likely suicidal in areas on that highway, it's hard to access what was actually on the road. If you're not getting other traction control warnings that make so sense, it sounds like it really did activate properly.

The camera and ultrasonic sensors are not used as part of traction control. | January 18, 2020

"...that make no sense..."

Stiction | January 18, 2020

Ok TT, that seemed like the most probable thing but I was really watching for anything on the roads after the first event and when it happened the second time there was nothing there I could see.

The road on that side (Cruz) is very smooth.

And in both cases it was not helping me at all. It was trying to put me into the barrier to the left.

Bighorn | January 18, 2020

Does AP1 have Lane Departure Avoidance and Emergency Lane Departure Avoidance? I’ve never seen any issue with AP0 on that stretch. Irregular surfaces can trigger TC, most notably on potholes, like TT said. It’s very easy to push the limits of traction at speed on those curves.

Anthony J. Parisio | January 19, 2020

How old are your tires? You might want to check the wear on your the shuttering tire.

Stiction | January 20, 2020

tires have less than 5k miles.