If your macro for the save is named btnSave_Click, the syntax would be like this:
DoCmd.RunMacro "btnSave_Click"
If you are running it as an embedded macro, see
http://office.microsoft.com/en-us/access/HA012142021033.aspx#embeddedmacro please provide more details as to what "doesn't work" means.......didn't compile? didn"t execute? error messages?