Start by connecting your Garmin Nuvi to your PC with the included USB cable. After a brief loading screen, your Garmin should display the Garmin logo and a small image indicating the connection was successful. At this point, your PC should recognize the connected Nuvi.
Install Garmin Agent
In most cases, your PC will prompt you to install an application called Garmin Agent. If your weren't prompted, don't panic. Simply visit http://www.garmin.com/agent to download the software.
Garmin agent resides in your system tray and directs you to the MyGarmin Web site when a Garmin device is connected.
Once at the MyGarmin Web site, you'll be prompted to install another bit of software, Garmin Communicator.
Garmin Communicator lets your Garmin Nuvi device interface with Garmin's Web site for software updates. Why Communicator and Agent aren't packaged into one application is beyond us. Once Communicator is installed, you may be prompted to reboot your computer.
Once your computer reboots, double-click the Garmin Agent icon in your system tray to be once again whisked away to the MyGarmin site where you should see that your Nuvi model has been recognized. From here, you will see if there are any available map updates. This is also where you can find firmware updates, if available.
Most Garmin devices come with a new maps guarantee that entitles you to one free map update within the first 30 days of your purchase. A few newer models are sold with free quarterly map updates for the lifetime of the unit.
If you're outside of your 30 days and don't have a lifetime map subscription, you can purchase a one time map update for about $70 or, for about $120, purchase a lifetime update subscription.
Map purchase history
Once you've chosen (and paid for) your maps, you'll be taken to a map downloads page that lists product keys for your map updates. This is our second map update for this device, so there are two product keys listed here. Once you're ready to update your new maps, click the blue Download button.
Download Garmin Map Update application
Next, you'll be prompted to download the Garmin Map Update application--that's right; it's a third application, but don't worry, this is the last one.
Garmin Map Update
The Garmin Map Update application handles the downloading, preparation, and installation of map data. It should automatically pull your map product key from the MyGarmin Web site. If it doesn't, you'll be prompted to input the key before the download commences.
Download and you're done
The maps and POIs for North America are about 2GB worth of data, so set some time aside for a big download. The Garmin Map Update application warned us that a full update could take several hours. In our experience, the process required only one hour.