I think I know what the problem is. If it will only let you go to lets say 38.599...it could be in the wrong mode. One mode is decimal degrees and another is I think deg/min/secs.

For example 38.5000 in one mode is the same as 38/30/0. The first number stays the same .5 is read one half. Thus in the deg/min/sec it would be 30 because 30min is half an hour.

If that is the problem go to gps settings and change the mode to decimal degrees. Hope this helps.

Odie