A backplane or a connection to the backplane might be failing. Use this procedure to identify which backplane might be failing.

Note: Before replacing any parts, verify the connections to the backplane.

1. Were you sent here by a power reference code (1xxx xxxx)?
   • No: Continue with the next step.
   • Yes: Go to SYSBKPL. This ends the procedure.
2. Determine the location of the device by performing the following:
   1. Use the location information in the error log if it is available. If no location information for the device is available, use the location information for the I/O adapter instead.
   2. If no location information is available for either the device or the I/O adapter, find the address of the device or I/O adapter (see System reference code (SRC) address formats, or see "System reference code (SRC) address formats" in the service guide for the system unit. Use the address to find the location (see Locating FRUs, or see "Locating FRUs" in the service guide for the system unit.
   3. Any backplane connecting the device or I/O adapter might be the cause of the problem. Use the location code to determine in which unit the device, cable, and the connected backplane are located. Then use the following table to determine the part number for the field replaceable unit (FRU):

      CCIN or FFC	Type and model	Part number	Description	Location code
      	8204-E8A	10N9369	System backplane	Un-P1
      	9406-MMA, 9117-MMA	42R7352	I/O backplane	Un-P1
      28BB	5790, 7311-D11	80P6626	I/O backplane	Un-P1
      	0595, 5095, 7311-D20	39J0515	I/O backplane	Un-P1
      520C	5796, 7314-G30	10N7677	I/O backplane	Un-P1
      28B7	5094	39J3058	I/O backplane	Un-CB1

      This ends the procedure.