While many seek a "download," these units are notoriously picky about the quality of burnt CDs.
Turn on the ignition (position II) but do start the engine to avoid voltage fluctuations. Insert the new navigation CD into the drive.
Because a CD only holds 700MB, you cannot download a "Map of Europe" for the NCDC 2013. You must find specific ISO files for the specific regions you intend to travel in. This often leads to users swapping CDs mid-journey, a process that can be cumbersome and distracts from driving.