IBM 3270 Maintenance Manual page 205

Do the following:
1.
Press 0 (RUN DIAGNOSTIC ROUTINES)
then Enter.
2. Depending on the configuration of your
system, questions about attached devices may
appear on your screen. Press Y or N as
required, then press Enter.
3. Press Y or N (IS THE LIST CORRECT?) then
press Enter. (If the list is incorrect, follow
the instructions on the screen to correct the
list before answering yes. If you cannot
correct the list, you must still answer yes to
continue.)
CONTINUE
3~600-6
Maintenance Information