Hard Key
This diagnostic tests the interface dial, the buttons that surround it, the audio remote switch, and the HFL-navigation voice control switch. For this model, the interface dial and buttons use the serial bus for communications.
To complete the test, touch each button on the vehicle's control panel, and move the interface dial to each indicated position. As each function is tested, the corresponding button on the display should highlight.
To exit, push in and hold the selector knob.
NOTE:
You cannot use the onscreen return button to exit this function