Direct downloads for the RNS 315 v.4 (or higher) map update to a standard SD card are not officially supported. Unlike newer Volkswagen infotainment systems, the RNS 315 uses a proprietary security system where map data is tied to a unique hardware ID (CID) on official Volkswagen SD cards. Update Options and Restrictions
Proprietary Security: The system requires a "protected" SD card. Even if you find the map files online, a standard SD card will be rejected by the unit because it lacks the correct CID and security lock.
Verify Version: Version 4 (v.4) is quite old. The latest widely available version for many regions is V12. Installation Steps: Start the engine or turn the ignition to "On". Insert the SD card into the slot on the infotainment unit. When the pop-up appears, select "Assign" or "Install".