Hi
I was talking on the basis of your screenshot of the debugging session.
In your system, If you run function Module "CONVERSION_EXIT_MATN1_OUTPUT" from se37, and input as 017-001813 then what is the output coming.
In our system output is same as input.
Looks like some conversion routine inside the function module is converting it to 3- in your case.
Regards,
Sarbjeet Singh