On Fri, 17 Jan 2020 23:07:36 -0000 (UTC), news18
wrote:

On Fri, 17 Jan 2020 21:04:23 +0000, Ted Heise wrote:
The camera usage is amazing. My car shows current speed limit on the
Car Play screen when I have Google mapping in use. It is occasionally
wrong; I'm pretty confident it comes over the phone from some Google
database.

It does. We noticed this years ago when there was a large scale change
throughout the state to expand town/city boundaries and often the garmin
device with its advisory voice was clearly wrong about when the speed
limit had changed.

I don't think Google Maps devices allow editing the database to
correct speed limits. AFAIK, you send email to Google Feedback and
hope that someone eventually fixes the data:
"Speed Limit Alerts - Editing the Posted Speed on Google Maps"
https://mastrack.zendesk.com/hc/en-us/articles/206572427-Speed-Limit-Alerts-Editing-the-Posted-Speed
"Incorrect speed limits during navigation"
https://support.google.com/maps/thread/10569346

Garmin does allow changes:
"Correcting speed limits on Automotive devices"
https://support.garmin.com/en-US/?faq=Y06fiWRwZQ5zov3DrZ7we9
"Reporting Map Errors on Automotive Devices"
https://support.garmin.com/en-US/?faq=pJLZBzPen9A7OXw5vlRyu5

However, I don't use Garmin's maps and data, which I've replaced with
OpenStreetMap (and OpenCycleMap). If you want to make changes, just
edit the speed limit sign tags in the database:
https://wiki.openstreetmap.org/wiki/Speed_limits
https://wiki.openstreetmap.org/wiki/Key:maxspeed
http://mijndev.openstreetmap.nl/~peewee32/maxspeed/Maxspeed.htm

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558