Autopilot Max Speed

[pobguy]

Here's a question about something that puzzles me. I have a 2021 M3LR. When driving on 2-lane highways using Autopilot (not FSD), set the max speed to be the speed limit (say, 55 mph). When the speed limit changes to, say, 40 mph, the max automatically goes to 45 mph (i.e., 5 mph over the speed limit). When the speed limit returns to 55, the max does it also, without any intervention from me. So here's my question: When in the 40 mph zone, why didn't the max go to 40 rather than 5 mph higher? In the autopilot menu, I have the "offset" set to 0

 

[Supcom]

Here's a question about something that puzzles me. I have a 2021 M3LR. When driving on 2-lane highways using Autopilot (not FSD), set the max speed to be the speed limit (say, 55 mph). When the speed limit changes to, say, 40 mph, the max automatically goes to 45 mph (i.e., 5 mph over the speed limit). When the speed limit returns to 55, the max does it also, without any intervention from me. So here's my question: When in the 40 mph zone, why didn't the max go to 40 rather than 5 mph higher? In the autopilot menu, I have the "offset" set to 0

I assume that when you say you were not using FSD, that you do not have FSD, only the basic AP.

This one puzzles me since basic AP is not supposed to react to changes in speed limits. That requires FSD. However, perhaps what is happening is that you are entering a city limits and autopilot has some limited ability to change speed to some default for the city streets? Then, as you exit the city limits, autopilot restores your previous speed limit.

The fact that the speed was not set correctly, implies to me that the car was not responding to the speed limit sign, but instead, reacting to the map's city limits.

 

[TresLA]

Working off some assumptions here, but it sounds like the 55 MPH road you set the speed limit for is a highway entering what’s considered a surface street (some roads I consider surface streets are actually categorized by Tesla or whatever mapping source as a highway). Auto steer is limited to 5MPH over the speed limit on surface streets, but is limited only to 85 (or 90 if your car was manufactured before May 2021).

I’ve seen these kinds of roads in more rural areas of the country that switch back and forth as you drive into a small town and exit the other side, but basically you’re going from Navigate on Autopilot (NoAP) to surface streets AP, then back to NoAP. Since you set the speed limit to 55, it’ll change to 45 since that’s 5 over the speed limit, then switch back to what you set once you’re back to NoAP (highway).