cannot change linetype

I am working on a road design project and I would like to change the linetype of the centerline to show as DASH or CENTER. when I select the line and change the linetype in the properties window nothing changes on my drawing. The line was created in another road design program and saved as a DWG to be opened in Autocad.

Perhaps it did change but the linetype scale is such that it is not readily apparent.

change your linetype scale and than see

based on your user details, you're on C3d 2009, perhaps changing the current annotation scale would be a better choice than the line's linetype scale (assuming msltscale is set to 1)