depot repair service code

dear all,

i am trying to implement depot repair for the first time using wip mode.

i have some issue in diagnostics tab:-

1. can i use diagnostics tab to enter service code area without using diagnostics code area, and Solution area .

if yes,

i did all needed setup (define service code link with inventory item, define bill of material ...etc)

but when test my setup , service code lov is not shown values .

please help me what i miss. and what area to check.

best regards