Mapping rules can have no visible link if they use only functions
or a default value.
To remove mapping rules with no links:
Procedure
Select the destination node and right-click.
Select one of these options:
Define Default Value. If the
node has a default assigned. Remove the default value in the Default
Value window and click OK.
Edit Function Graph. If the node
has a function graph assigned. Once the function graph is expanded,
right-click the function and select Delete Mapping.