Most Garmin GPS units can transfer data using data cards. Garmin units utilise either SD cards containing Garmin maps or proprietary Garmin-specific data cards. To facilitate the process of transferring their maps, Garmin allows users to add data to their own data cards. This allows users to download new maps directly from Garmin's online store and transfer them onto an SD card or proprietary Garmin data card. Some maps may also require online activation to deter map piracy.
Purchase, download and install the map that you would like on your data card from the Garmin Map Store in the Resources section. Install the MapSource software that is included with the download.
Plug your Garmin Data Card Programmer or SD Card reader into your computer. Allow your computer to install the necessary drivers. Insert a Garmin Data Card into the Data Card Programmer or insert a SD Card into the SD Card reader.
Open the MapSource software from your "Programs" folder. Select "Send To Device" from the "Transfer" menu to bring up the map transfer dialogue.
Select "USB Data Card Programmer" if you are using a Garmin Data Card Programmer or the drive letter of your SD card. Select the data that you want to install onto the device in the "What to Send" area. Click "Send."
Close MapSource and disconnect the Garmin Data Card Programmer or SD Card reader from your computer.
Transferring new maps to your data card will erase all of the original data on the card.