You have to set "DesiredAccuracy" before "PositionChanged" event handler (Similar question).
_GeoLocator.MovementThreshold = 1;
_GeoLocator.DesiredAccuracy = PositionAccuracy.High;
_GeoLocator.PositionChanged += (Geolocator sender, PositionChangedEventArgs args) =>
{
//UpdateLocation(args);
Console.WriteLine("Position Changed");
};