I have a Nuvi 3490LMT with the latest firmware (6.20) and updates. When I create waypoints or routes, I am unable to copy them to 16gb sd card in the 3490 using Basecamp. I get an communication error notice after it tries to copy to the sd card. On a side note the same thing happens if I try to save topo maps to the sd card using Map Install. Removing the card and installing the topo via a card reader works fine and the GPS can see the topo maps as well. I thought I might have an issue with the card and I tried with an 8gb card with the same results. Single waypoints copied to the internal storage do not show up in "Saved" either but routes do. Any ideas?
Edit: I don't know if it is related but Basecamp can not see the topo maps on the sd card either.
You might want to try to set your GPS to MassStorage mode and try again.
1) Go to the 'Volume' screen.
2) Press the upper right corner of the screen until you get an auxiliary menu.
3) Scroll to and press 'MTP Settings'.
4) Change from 'MTP Auto Detect' to 'Mass Storage'.
5) Press 'Save'.
Okay, I have had a little time to experiment with different micro SD cards in the unit and what I have found is that Basecamp and MapInstall will not write to the micro SD card while it is in the 3490 if it is larger than 4 GB. I have tried 2GB and 4GB cards and they all were fine while 8GB and 16GB would not work. In order to install maps to an 8GB and 16GB with Mapinstall the card had to be removed from the GPS and inserted into a Card reader. BTW now running firmware 6.30
