Neither main Honda dealer who supplied my Civic nor my local Honda dealer knew about updating Honda Garmin Sat Nav system now installed in some Civic, CR-V, HR-V & Jazz models. @Ichiban please correct models if incorrect. My local dealer took trouble to find out and the answer is go to https://honda.garmin.com/honda/ If you go to next page of website you will note that engine may need to be left running for up to an hour for update to take place after USB with update downloaded on it has been plugged into the car. This might pose a problem for dealers if you leave it to them to install updates. I am waiting to receive the 16GB USB memory stick to try an update myself. My Car was registered in May 2015 but many speed limits shown by Garmin Sat Nav are incorrect.