IBM 7012 300 Series Installation And Service Manual page 53

If the symptom did not change and all the disk drives have been
exchanged, in the following order exchange the FRUs that have not been
exchanged:
For Models 320, 32E, and 32H with bus-attached or SCSI-attached disk
drives:
1. Riser card (if present)
2. SCSI adapter (if present)
Note: Refer to POWERstation and POWERserver Common
3. SCSI cable (if present)
4. System planar
5. Power supply.
For Models 340, 34H, 350, 355, 360/36T, 365, 370/37T, and 375,380,
390, 39H, and 397:
1. SCSI bus extender card
Note: Refer to POWERstation and POWERserver Common
2. SCSI cable
3. System planar
4. Voltage regulator card (Model 39H)
5. Power supply.
If the symptom did not change and all the FRUs have been exchanged, call
your service support person for assistance.
If the symptom has changed, check for loose cards, cables, and obvious
problems. If you do not find a problem, return to Step 1 in this MAP and
follow the instructions for the new symptom.
YES Repeat this step until the signal and power connectors for all the disk drives
have been connected.
For Models 320, 32E, and 32H, go to Step 11.
For Models 340, 34H, 350, 355, 360/36T, 365, 370/37T, and 375, 380, 390,
39H, and 397, go to Step 10.
Diagnostics and Service Guide , Chapter One; SCSI-1 Adapter
Fuse Blowing.
Diagnostics and Service Guide , Chapter One; Integrated
SCSI Fuse Blowing .
Maintenance Analysis Procedures
2-1540-11