b.
Remove
the
power
supply
from
the
system
unit
and
replace
it
with
the
new
one.
c.
Power
on
the
system.
Does
a
power
reference
code
occur?
v
Yes:
Perform
the
following:
a.
Remove
the
new
power
supply
that
was
installed
in
step
6
(See
page
and
reinstall
the
original
power
supply.
b.
Replace
the
backplane.
See
symbolic
FRU
This
ends
the
procedure.
v
No:
The
power
supply
that
was
removed
earlier
in
this
step
was
the
failing
item.
This
ends
the
procedure.
7.
Perform
the
following:
a.
Reinstall
all
of
the
cards
you
removed
in
step
2
(See
page
b.
Power
on
the
system.
Does
a
power
reference
code
occur?
v
Yes:
Continue
with
the
next
step.
v
No:
Go
to
step
9
(See
page
8.
Perform
the
following:
a.
Power
off
the
system.
b.
Disconnect
one
of
the
cards
you
reinstalled
in
step
7
(See
page
c.
Power
on
the
system.
Does
a
power
reference
code
occur?
v
Yes:
Have
you
disconnected
all
the
cards?
–
No:
Repeat
this
step.
–
Yes:
Install
all
parts
removed
in
this
procedure
and
go
to
This
ends
the
procedure.
v
No:
Exchange
the
last
card
you
disconnected
in
this
step.
See
the
for
the
model
you
are
working
on.
This
ends
the
procedure.
9.
Perform
the
following:
a.
Power
off
the
system.
b.
Reconnect
all
of
the
I/O
devices
(tape,
diskette,
or
disk
units)
that
you
disconnected
in
step
2
(See
page
c.
Power
on
the
system.
Does
a
power
reference
code
occur?
v
Yes:
Continue
with
the
next
step.
v
No:
The
system
is
working.
The
problem
seems
to
be
intermittent.
This
ends
the
procedure.
10.
Perform
the
following:
a.
Power
off
the
system.
b.
Disconnect
one
of
the
I/O
devices
(tape,
diskette,
or
disk
units)
that
you
connected
in
step
9
(See
page
c.
Power
on
the
system.
Does
a
power
reference
code
occur?
v
Yes:
Have
you
disconnected
all
the
I/O
devices?
Analyze
hardware
problems
155
