The beginning of this route does not exist. The (only) access to the fields in the south west is via the drivable way that is indicated here as a stippled red line. 

Compare to google maps: 
https://www.google.de/maps/place/Traubenbergstra%C3%9Fe,+66424+Homburg/@49.2648774,7.3259745,18.75z/data=!4m5!3m4!1s0x4795d0455f266287:0x640686eb78db491e!8m2!3d49.2656283!4d7.328615 