Use the main menu > GPS > Erase Specific Maps command to open window with list of maps to be erased. The list is empty when window opens.
Click on Get Map List from GPS button to download list of maps from the Garmin GPS unit.
Click on Get Map List from IMG file button to load list of maps stored in the IMG file on PC. IMG file can contain single map or map set with many maps. Users can build and edit their map set on PC and then load it to multiple GPS units. Use this option to erase specific maps from your map set file on PC, without need to work with GPS. Mark maps to be erased by clicking on the respective line of the Erase column.
When finished, click on button to perform erasure. All maps marked by X sign will be erased. This operation may last even several minutes.