Solution : https://service.sap.com/sap/support/notes/921112 (SAP Service marketplace login required)
Key words :
'functional area' field caufvd-func_area, 'functional area' text field, 'functional area' field, 'additional data' tab, execute transaction se51, 'layout editor' subobject, plant maintenance order, enter screen number 1130, caufvd-func_area, func_area reason
Related Notes :
| 535318 | IW31: SAPLCOBH termination not_found (AUFK-func_area) |
| 420382 | Functional area cannot be changed in the PM/CS order |
| 317710 | Functional area field is invisible in PM/SM order |