Lenovo TC A51-8122 Manuel D’Utilisation
Power
supply
and
system
board
Diagnostic
LEDs
You
computer
has
two
LEDs
located
on
power
supply
on
the
back
of
the
chassis.
The
power
button
LED
located
on
front
of
your
computer
and
the
two
LEDs
on
the
back
will
help
you
determine
if
the
power
supply
or
system
board
is
working
correctly.
The
following
table
uses
the
LEDs
to
diagnose
possible
power
supply
and
system
board
problems.
Power
Button
LED
Green
LED
Yellow
LED
Diagnosis
Off
Off
Off
Check
the
following
first:
v
Is
power
cord
plugged
in?
v
Is
the
power
strip
on?
Failing
power
supply
Off
(After
pressing
the
power
button)
On
Off
Failing
system
board
On
On
On
Failing
power
supply
On
On
Off
Normal
working
conditions,
but
if
your
computer
is
not
working
correctly
then
you
have
a
failing
system
board
or
a
failing
microprocessor
If
you
cannot
correct
the
problem,
have
your
computer
serviced.
Note:
To
reset
the
computer
once
a
yellow
LED
is
on,
unplug
the
power
cord.
PC-Doctor
for
DOS
Diagnostics
The
PC-Doctor
for
DOS
Diagnostics
program
runs
independently
of
the
operating
system.
You
can
use
this
program
to
test
hardware
components
of
your
computer.
You
can
use
this
program
when
other
methods
are
not
available
or
have
not
been
successful
in
isolating
a
possible
hardware
problem.
You
can
run
the
diagnostics
from
the
Rescue
and
Recovery
workspace
on
your
hard
disk.
Alternatively,
you
can
create
bootable
diagnostics
diskettes
from
the
Rescue
and
Recovery
workspace.
You
can
also
download
the
latest
version
of
the
diagnostics
program
from
http://www.lenovo.com/think/support/
on
the
World
Wide
Web.
Type
your
machine
type
and
model
number
into
the
Quick
Path
field
to
find
the
downloadable
files
that
are
specific
to
your
computer.
Chapter
5.
Troubleshooting
and
diagnostics
25