One issue is DMS is a string and you need to convert it to a number (Double) so you can plot them
The basic conversion is dd = d + m/60 + s/3600
you could field calculate it in ArcMap two fields DMS has the dms values, and DD a double field where you want to field calc it
.DD= left( [DMS],2) + (mid( [DMS],4,2)/60) + (Mid( [DMS], 7,4)/3600)
The left and mid functions are a way to pull apart the string, in your example
30°11'4.46"N you want the left 2 (maybe 3 if in western hemisphere ie. -30) Mid 4,2 gets the 11 and mid 7,4 gets the 4.46 The °'."N symbols are not math symbols..