Missed this also but finally after checking the expert serie youtube find that you must have nav1 nob to fm1.
Then later on when for example use ils change nav1 nob to v/ils1
Hope that helps 
Missed this also but finally after checking the expert serie youtube find that you must have nav1 nob to fm1.
Then later on when for example use ils change nav1 nob to v/ils1
Hope that helps