How to know if navigation (routing) is active ?

Hello,

I am writing an extended data field to enrich map display on Edge 830/1030.

Is-there an IQ field to know if navigation (routing) is currently active ?

My goal is to display "Distance to Destination" value only if navigation is active. 

So I have to do a "test" to know know if navigation (routing) is currently active ?

Thanks for your help.