The problem is in a mezzanine bus arbiter, replace the I/O backplane. Use the following table to determine the FRU part number.
CCIN
Description
Model, expansion unit, or unit type
Part number
2D2
8204-E8A
10N9369
System backplane
Un-P1
2D2
I/O backplane
9117-MMA
42R7352
2D2
I/O drawer backplane
7311-D10
80P2339
2D2
I/O drawer backplane
7311-D11
23R0181
2D2
I/O drawer backplane
7311-D20
39J0515