heat transfer and stress analyses

Hi all!!

I am trying to use subroutine VUINTER in ABAQUS to extract the SFDR surface based interaction variable (Heat flux per unit area entering the surface due to frictional dissipation).

If i assume that the subroutine code I have written is correct, how can I request from the software to include SFDR in the field output variables? I am trying to add manually from the field output request dialog but i get a warning message that this is invalid.