Activating iDrive Service mode
1. From the main screen, press and hold the iDrive knob for 10 seconds, until the knob graphic on your screen changes
2. Turn the iDrive knob three clicks clockwise
3. Turn the iDrive knob three clicks counterclockwise
4. Turn the iDrive knob one click clockwise
5. Turn the iDrive knob one click counterclockwise
6. Turn the iDrive knob one click clockwise
7. Press the iDrive knob down and release
You can check your Nav OS version to make sure you have the lastest by selecting "MOST Devices", then Navigation and then scrolling down until you see "Software version"
You can also turn "RDS on" on your radio.