error
that
occurred,
and
see
“Light
Path
LED
errors”
on
page
147
to
help
determine
the
cause
of
the
error
and
the
action
you
should
take.
To
view
the
LEDs
on
the
various
main
boards,
look
at
the
board
indicated
by
the
diagnostic
panel.
To
acknowledge
a
system
error
but
not
take
immediate
action,
press
the
REMIND
button,
and
place
the
Light
Path
Diagnostics
feature
in
Remind
mode.
The
system-error
LED
flashes
in
Remind
mode.
If
a
new
failure
occurs,
the
system-error
LED
is
lit
again.
The
diagnostics
panel
The
diagnostics
panel
should
be
the
first
place
you
look
for
help
with
identifying
problems.
If
a
system
error
occurs,
the
system-error
LED
on
the
front
of
this
panel
is
lit.
Press
the
front
of
the
panel
to
open
the
diagnostics
panel,
and
look
for
any
lit
LEDs.
These
lit
LEDs
can
help
you
identify
the
possible
cause
of
the
error.
Make
a
note
of
any
LEDs
that
are
lit,
and
then
close
the
panel.
LEDs
on
the
top
of
the
server
You
can
also
use
the
LEDs
on
the
top
of
the
server
to
find
an
error.
If
the
BOARD
LED
on
the
diagnostics
panel
is
lit,
pull
the
server
out,
and
view
the
top
cover.
In
the
center
of
the
top
cover
is
a
set
of
six
LEDs
and
the
system
service
labels.
The
numbers
next
to
the
LEDs
correspond
to
the
numbers
on
the
system
service
label.
Note
the
lit
LED,
and
see
the
numbered
block
on
the
system
service
label
that
corresponds
to
the
lit
LED.
Then,
follow
the
instructions,
if
any,
in
the
numbered
block.
LEDs
on
the
system
boards
To
locate
the
actual
component
that
caused
the
error,
locate
the
lit
LED
next
to
that
component.
For
example:
A
system
error
has
occurred,
and
you
have
noted
that
the
CPU
LED
is
lit
on
the
diagnostics
panel.
Referring
to
the
LEDs
on
the
top
cover,
you
see
that
LED
2
is
lit.
You
then
locate
the
panel
on
the
system
service
label
with
the
number
2
on
it.
In
this
case,
the
instructions
in
the
panel
tell
you
that
the
problem
occurred
with
one
of
the
microprocessors.
Follow
the
instructions
to
remove
the
processor-board
assembly.
See
“Processor-board
assembly”
on
page
119.
Located
on
the
circuit
board
is
the
light-path
capacitor
switch.
Press
and
hold
the
switch
until
you
locate
the
lit
LED
next
to
the
defective
microprocessor.
Follow
the
instructions
in
“Microprocessor
and
power
module”
on
page
121
and
“Installing
and
replacing
a
microprocessor
and
power
module”
on
page
100
to
remove
and
replace
the
microprocessor.
For
more
information
about
LEDs
and
connectors,
see
“Connector
and
LED
locations”
on
page
80.
Diagnostic
display
If
a
problem
is
detected
with
system
power
on
or
during
initialization,
the
two-hex
character
diagnostic
display
on
the
midplane
board
might
show
an
error
code.
See
“Midplane
board
connectors
and
LEDs”
on
page
84
and
“Diagnostic
display
error
codes”
on
page
181
for
more
information.
Chapter
3.
Diagnostics
37