The expander might be failing. Perform the following:

1. Does the SRC that sent you here begin with 509A?
   • No: Go to step step 3.
   • Yes: Continue with the next step.
2. Find the resource name that this error was logged against. This can be obtained from the Service Action Log (see Using the Service Action Log). Then, using the resource name, perform the following:
   1. Access SST or DST.
   2. Select Start a Service Tool.
   3. Select Hardware Service Manager.
   4. Select Locate resource by resource name.
   5. Enter the resource name that this error was logged against.
   6. Select the Associated packaging resource(s) option for the expander.
   7. Select the option to Display detail for the expander to display its physical location.

   Replace the expander at the location displayed. This ends the procedure.

3. Is the device an internal device (not in an external disk expansion unit)?
   • No: Replace the expanders in the external disk expansion unit one at a time until the problem is resolved. This ends the procedure.
   • Yes: The expander is integrated into the device backplane.

     If you have not replaced the device backplane, replace it. Use the following table to determine the part number for the field replaceable unit (FRU). If you have already replaced the device backplane, continue with the next failing item in the failing item list. This ends the procedure.

     CCIN or FFC	Type and model	Part number	Description	Location code
     	7041-SD1	42R7599	Enclosure Services Manager (ESM)	Un-P3
     	8204-E8A	10N9664	Disk drive backplane with port expander	Un-P3
     	9406-MMA, 9117-MMA	10N9088	Disk drive backplane	Un-P3