Touch Screen Display (TSD) And Navigation Diagnostics: Notes
WARNING: This page is about a different car, the 2006 Land Rover Range Rover. However, it is still accessible from the selected car via links, so may be relevant.
The TSD and the navigation module both have built in self tests that allow the technician to diagnose fault conditions. Fault codes and diagnostics can also be retrieved/achieved using the manufacturer approved diagnostic system.