One of the hardest problems for Tesla’s Full Self-Driving (FSD) system has been to take smooth and safe unprotected left turns (UPLs).
This problem was first officially acknowledged by Tesla in 2022 when Tesla owner Chuck Cook showed them FSD v10 struggling at a difficult UPL in Jacksonville, Florida. The AI automaker began special training at this turn and also started sharing the improvement status in the FSD v10.13 release notes.
It has been more than 3 years since Tesla’s internal FSD testing team has been constantly trying to learn and improve the UPL performance of its self-driving AI system. The data they have collected, along with the external beta testers, is now showing significant improvement.
Tesla started rolling out FSD v14 earlier this month. Chuck Cook tested the latest release, FSD v14.1.2, on his difficult UPL. The way it took this UPL was more than impressive — it looks stunning (watch below).
Chuck performed these UPL tests in JAX during a twilight hour (Friday morning around 7:15 AM). This is the time when there is low natural light and the vehicles were all coming from left and right with their headlights turned on.
Influential Tesla YouTuber took multiple attempts at the same unprotected left turn (UPL) on his AI4 Tesla Model Y, with FSD v14.1.2 and car running on Mad Max mode (not much impact on FSD aggressiveness).
Just before the UPL, there’s an NHTSA stop at this location in JAX. FSD v14 felt relaxed at the Stop sign and crept carefully like a human ideally would. Traffic coming from the left was detected and perfectly visualized on the center display of the vehicle.
In all of these UPL attempts, the Tesla vehicle sat in the median perfectly. The position of the vehicle was ideal to look at the traffic coming from the right, and it pre-rolled safely before moving ahead to the left.
“The best thing it’s doing is getting itself in the median at a great angle, so that it could sit there and wait,” Chuck praised FSD v14’s UPL performance.
In one attempt, when the traffic from the right side was at a safe distance, FSD v14.1.2 didn’t stop in the median and moved ahead with constant acceleration. “Same behavior — smooth — no brake-stabbing, no pausing, really, really good,” Chuck Cook expressed his joy after a smooth UPL.
Moderate to heavy traffic was observed at around the sixth attempt at this UPL. However, FSD v14.1.2 took the UPL with the same precision with heavy traffic coming from both sides as well.
Chuck also wrote the following in an X post:
I’m so impressed with what Tesla AI has done on this very complex traffic pattern. Safety-critical systems are NOT easy to deploy to the masses. Don’t underestimate the importance of this core Tesla capability.
One Disengagement / Human Intervention
The only disengagement in Chuck’s UPL testing from yesterday was for a motorcycle due to safety concerns. The headlight of this motorcycle was turned off, and Chuck intervened and took over his Tesla to be extra safe.
Remember, Tesla FSD v14 is still a Supervised version of the software. Chuck Cook delivered the final verdict on the overall UPL performance and this intervention in the following words:
Hey, Tesla, the brake-stabbing and the smoothness on FSD 14.1.2 are obvious in these dynamic situations with lots of traffic.
It did a perfect job executing the question mark every single time. I think its decision-making was probably perfect every time.
I disengaged one time for a motorcycle. Maybe in post analysis with the video I provide, you guys can do your own assessments and whether or not I could have gone or not.
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