IBM 3270 Maintenance Manual page 422

1.
Set the Power switch on the system unit (and
expansion unit, if attached) to Off.
2. Reconnect the right drive power supply
connector.
3. Set the Power switch on the system unit (and
expansion unit, if attached) to On.
IS THE RIGHT DRIVE A DISKETTE DRIVE?
NO The right drive is a fixed disk drive. Go
to page 3-1700-4.
YES
October 1984 3-9999-17