I don't have the information on wire colours for connecting a Yeoman to a Navman but I think you are expecting a functionality which doesn't exist. Unless things have changed since I had a Yeoman Plotter, the only things that can be uploded from the Yeoman to a GPS/plotter are waypoints. Probably sends the "WPL" NMEA word to achieve this so you need to check that your Navman can decode and accept this input.