The problem is in a PCI Differential ultra SCSI controller. The controller could be integrated on a backplane or on a PCI adapter. For the failing FRU part number, see the following table.
| CCIN | Description | Model, expansion unit, or unit type | Part number |
| I/O backplane | 9117-MMA | 42R7352 | |
| SCSI PCI adapter, see Managing I/O adapters, SA76-0092 for FRU part numbers | 9117-MMA | ||
| I/O drawer backplane | 7311-D11 | 80P6626 | |
| I/O drawer backplane | 7311-D20 | 10N7677 |