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TACC slow to brake for cross traffic

TACC slow to brake for cross traffic

Driving along city streets with TACC enabled, when a car makes a turn a couple of hundred feet in front of me, crossing my path, it seems that my Model 3 doesn't even apply the brakes until the turning car is already out of my path. Then it abruptly slows down and I have to press on the accelerator to speed back up.

I would think the computer would react more quickly than that. Of course, I can see the car preparing to turn even before it enters my lane, and I can judge its motion and inertia and clearly see that it will be out of the way well before I get to it, but with a microprocessor and radar and/or front camera, it just seems surprising that the Model 3 is so slow to react.

NOTE: For those of you preparing to admonish me to read the manual, and warn me that TACC is only for highway use, I am well aware of the "official" position from Tesla. I also know that when I got my car over a year ago EAP only worked on limited access highways, but at some point last year it suddenly started working on city streets. To me it's obvious that Tesla wants to collect data from city driving and though they can't officially endorse it, I am helping them by using it anywhere it will engage.

don | April 15, 2019

I haven't seen that behavior probably because I rarely use it on city streets but I have noticed while driving on the freeway once in a while it will react to a car in the lane beside me, hitting the breaks fairly hard but then back off.

Bighorn | April 15, 2019

One of those things that will get better with time and firmware.

Pepperidge | April 15, 2019

I usually apply accelerator before the car trying to slowdown when I know it is not necessary to slowdown.

Magic 8 Ball | April 15, 2019

I have not heard that the car would brake for cross traffic in any situation.

wiscy67 | April 15, 2019

I concur the system can be improved over time. So far I enjoy my driving over the car's best guesses. I had something similar as you but on a freeway. It's not technically cross traffic but here in CA when cars are crossing lanes rapidly to get to an HOV entrance it can seem like cross traffic. I was using TACC and could see traffic up ahead was crawling as I approached. Before I got to the congestion a car in front of me crossed into my lane on its way to the HOV entrance. TACC kicked in and slowed me down (this is good) but when the car exited my lane TACC then sped me up toward the congestion which was only about 20 yds ahead (this was bad). I would have preferred to keep the slow pace as I entered the crawl. I get the feeling the car is just not looking far enough ahead to get the big picture sometimes.

SteveWin1 | April 15, 2019

You are absolutely correct, OP.

As @Pepperidge said, just tap on the accelerator when you notice someone in front of you turning or someone crossing your path that you know is not a threat. It will override the braking. This is probably the most annoying thing about AP right now, IMO. But, I'd much prefer that it brake when it doesn't need to than for it not to brake when it does need to. I'll tolerate a lot of false positives to prevent any false negatives. Its probably a necessary trade-off for now until it improves a little more.