In a post on X, Elon Musk mentioned that FSD V12.5 for Hardware 3 vehicles will soon be receiving a smoothness upgrade. This was in response to a user post that they have encountered a lot of phantom braking on FSD V12.5.4 with Hardware 3.
As a HW3 owner with V12.5.4, I can certainly agree with that—there has been a significant increase in phantom braking, especially near and around green lights or traffic merging from behind the vehicle.
For context, phantom braking is when the vehicle uses the brakes harshly for seemingly no reason. There isn’t a single reason for phantom braking, but it could be related to harsh light, the front cameras being obscured, or the vehicle detecting an incoming object across its path.
This smoothness upgrade will hopefully prevent the issues that users—myself included—have been experiencing on FSD V12.5.4, along with other improvements to make the ride smoother. FSD 12.5 currently doesn’t pass the “coffee cup” test like HW4. FSD V12.5 was initially touted as the comfort update, and while it is smoother than V12.3.6, there is still a lot of work to do.
We’re hoping the next update for V12.5 will bring additional braking smoothness to HW3 and better-timed decision-making. V12.5.4 still leaves lane change decisions to the last few seconds, resulting in changing lanes right before your exit. This can result in a jerky or somewhat unexpected motion if you’re going down a new route.
Either way, we’re looking forward to additional improvements to FSD and are happy to see the focus Tesla still has to improve FSD on older hardware. The next major FSD update is expected to include the end-to-end highway stack, just like the Cybertruck.