IBM 3274 User Manual page 97

Are all four indicators lit?
Y N
009
I
008
A communication problem exists between the 3274 and the
host system (no Carrier Detect from the modem).
Request assistance from your communication service
personnel. When the problem is resolved, all four
indicators will light.
Wait until all four indicators are lit and steady for 1
minute; then continue to step 009 of this procedure.
Perform a normal IML. Request the host system operator to
restore this 3274 to the active list, and resume operation. If
the problem recurs, request appropriate service.
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