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Speed limits

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I have had my "X" for 18 months now .I live in a rural area (out in the country ) in Michigan .
THe X has never had the speed limits right on some roads , namely the ones that unposted state limits .
However in the last month , it has lost all it's sense of the limits ..Almost all the limits on the roads that I drive have changed and not to the correct ones ..Some roads now show a correct limit one way and another the other way .
Other roads just show one limit regardless of the different limits over a few miles .
These are all 2 lane roads and it really messes with auto pilot ...I've now got my foot on the accelerator most of the time .
Most of the problem is a speed limit of 50 and the car thinks 35 ...
Called support , no help ..I have gone through 3 updates with no change .
Looking for advice and just living with it for now
 
The problem is with the new maps, not the OS. Roads are tagged as been unrestricted or restricted to a max of 5mph over the known limit while driving in AP (or less if you have that setting less than 5). The tag can be wrong—it has changed back and forth around here–and/or the known limit can be wrong. Keep filing bug reports so they eventually get the message along with coordinates for the error.
 
I have had my "X" for 18 months now .I live in a rural area (out in the country ) in Michigan .
THe X has never had the speed limits right on some roads , namely the ones that unposted state limits .
However in the last month , it has lost all it's sense of the limits ..Almost all the limits on the roads that I drive have changed and not to the correct ones ..Some roads now show a correct limit one way and another the other way .
Other roads just show one limit regardless of the different limits over a few miles .
These are all 2 lane roads and it really messes with auto pilot ...I've now got my foot on the accelerator most of the time .
Most of the problem is a speed limit of 50 and the car thinks 35 ...
Called support , no help ..I have gone through 3 updates with no change .
Looking for advice and just living with it for now
I helps to know what firmware release you are on and if you have the New Maps / New Nav when reporting these kinds of issues.
 
I have waited through the latest release hoping for a better experience ...currently on 18.20...I have the new mcu update ,or at least the maps load much faster ...I don't see much difference if , in fact, I have the new maps .
Speed assist has always been off ..And the problem is with the software as the speed limit window is showing the wrong number ..My rural area has many roads with very light traffic and auto pilot is very nice to use . A lot of these roads are 50 mph with signs showing this but the car ignores the signs ..My understanding is that the car cannot read the signs and works on the gps area . One odd fact : This change (crazy speed limits ) occurred when there was no update to the car ...Unless it happened without any notice ???
 
So , obviously I had a map update that screwed up the limits ...
THanks for all the comments ...I am going to keep complaining about it to Tesla (bug reports )
I am due to visit the SC in June and will make a stink about it there however the roads in question are in Michigan and my SC is in Ohio .
 
So , obviously I had a map update that screwed up the limits ...
THanks for all the comments ...I am going to keep complaining about it to Tesla (bug reports )
I am due to visit the SC in June and will make a stink about it there however the roads in question are in Michigan and my SC is in Ohio .

Unfortunately Michigan has to be one of the worst States in which to own a Tesla. State law precludes any sales in state, and no service center can be set up. I am amazed they allow Superchargers. Indiana almost became similar, but at the last minute, a Tesla specific exception was carved out. Good luck!
 
Since Tesla shifted to a different speed limit database provider last summer (TomTom?), the speed limit data has been much worse, with missing or incorrect (too high or too low) speed limits in many areas. And the situation hasn't improved much in the past year.

For Tesla to achieve their EAP/FSD goals, the software must have up-to-date road and speed limit data. The NAV 2.0 software fixes part of the problem by shifting routing to a cloud server, using up-to-date maps.

But AP2 cars are still using the onboard speed limit database - which impacts operations in three areas:
  • TACC can automatically set the target speed to the speed limit (plus a few miles, based on settings). If the speed limit is incorrect, this automatic speed limit setting will be incorrect - which is especially bad if the speed limit database has a speed limit too high (such as believing the speed limit is 55 MPH on a 40 MPH street). If you manually set the TACC target speed, you bypass the speed limit database, so you can workaround this problem).
  • AutoSteer will be restricted if the speed limit is too low. This can restrict the speed at which AutoSteer will operate and also prevent it from enabling lane change. There isn't any workaround for this, other than setting AutoSteer and manually increasing speed to what you want, and maintaining that speed until you hit a stretch of road that has the correct speed limit.
  • The most dangerous problem is when AutoSteer is operating at highway speeds, and you hit a section where the speed limit database has the road's speed limit below the AutoSteer threshold. When that happens, AutoSteer immediately begins slowing the car down - in the middle of high speed traffic. You can workaround this problem by disengaging AutoSteer and going back to manual operation OR you can manually increase your speed using the floor pedal. Though when the car immediately brakes in the middle of traffic, that poses a risk cars around you may not be prepared for this - and you could be hit from behind, if that driver isn't paying attention.
Shifting to a cloud-based routing server fixed most of the problems with the navigation system - Tesla still needs to fix the poor speed limit data.

Reading speed limit signs can help, though there are places where the speed limit signs are ambiguous (when multiple roads are running in parallel, such as HOV lanes, main lanes, exit/entry ramps, frontage roads) and it's not always clear which road the speed limit sign applies to. Plus, there are times when the speed limit signs are not visible (blocked by other vehicles).

Tesla really needs to fix this problem - either by shifting to an accurate and up-to-date speed limit database, or providing a way for cars and drivers to report back likely discrepancies - and distribute database updates more frequently.