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AP2 auto steer - adjust to speed limit automatically?

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Before Tesla switched the map data to tomtom (17.24.28, June 2017), my S90D would adjust speed when local road speed limit change. For example, when auto steer was set to 58 (55mph speed limit +3 relative), when road speed change to 50, auto steer will change the speed to 53 (50mph speed limit +3) automatically. This is very convenient and useful.

Ever since the 17.24.28 update, I lost the automatic speed adjust function; and, my S90D does not show road speed limit on most of the major local road.

Did Tesla change how auto steer setting the speed limit or my S90D have some sort of issue?
 
On our S 100D, the only time AutoSteer will change speed is when it believes the car has moved to an area where AutoSteer isn't supported at highway speeds. When that happens, AutoSteer will immediately adjust the speed downward and slow the car down.

Because of numerous errors in the new (TomTom?) speed limit data, this happens on several of the highways in the area with speed limits of 65+ MPH - and having the car quickly slow down to 45 or 50 MPH in the middle of high speed traffic isn't great, especially when the slow down is due to the software thinking the speed limit is 45, when it's really 65.
 
On our S 100D, the only time AutoSteer will change speed is when it believes the car has moved to an area where AutoSteer isn't supported at highway speeds. When that happens, AutoSteer will immediately adjust the speed downward and slow the car down.

Because of numerous errors in the new (TomTom?) speed limit data, this happens on several of the highways in the area with speed limits of 65+ MPH - and having the car quickly slow down to 45 or 50 MPH in the middle of high speed traffic isn't great, especially when the slow down is due to the software thinking the speed limit is 45, when it's really 65.

Hi Bob, thanks for sharing your finding!

I got so fed up with the speed limit, the lack of it, so I called Tesla yesterday. The support person ran a test/diagnostics remotely on my car, he said there few weird errors related to GPS and said that might cause the issue I saw. He forwarded the findings to the technical team so they can take a look what's going on. while on the phone, I asked him if auto-steer is supposed to reduce the speed while in auto-steer mode and road speed limit changed to lower, 55 to 50, for example; he said it is supposed to reduce speed limit accordingly.

On road speed limit, in my case, 80% of the major local road has no speed limit data, I think there is something wrong with my GPS, TomTom is bad, but, it should not be that bad.

I've started record what I see, the uploaded file shows what I am experiencing.

Tesla map issue with details.jpg
 
Unfortunately, it's probably not the GPS.

The speed limit database (TomTom?) is terrible - much worse than the previous data base.

We have a surface street near our house that is a 4 lane divided parkway with water between the two sets of 2 lanes. The posted speed limit is 40MPH. On one side, the software thinks the speed limit is 55 MPH - which causes TACC to set the speed to 60MPH if I let it auto-set the speed. On the other side, the software doesn't have any speed limit data at all.

And there are quite a few roads in our area that are missing speed limit data today - that had correct speed limit data a year ago, when we first got our S 100D.

When I first reported this issue, Tesla's customer support routed me to a website (Here?) where I could report the problems. I spent quite a bit of time reporting the correct speed limits on all of the roads around our house.

It's approaching a year since I did this - and haven't seen any improvement yet.

Because we should be seeing the new navigation software "soon", I recommend waiting until after your car gets the new navigation software and map data - and see if anything has changed. Hopefully they'll include an updated speed limit database or they've switched to a more reliable source (than TomTom?).