How to enter hidden service menu in RNS-D Navigation Plus (Audi A2 A3 A4 A6 A8)

Audi RNS-D hidden menu (diagnostic service mode Navigation Plus) can help you with troubleshooting issues with GPS navigation and radio tuner in your Audi car (A2 A3 A4 A6 A8). You can test FM tuner signal, GPS position, software version, tire settings, GALA, RDS. More at Music by Dan-O at