Cessna 172N - Page 134

SECTION
7
AIRPLANE
&
SYSTEMS DESCRIPTIONS
CESSNA
MODEL 172N
mounted
at the
edge of each instmment or
control and
provide
direct
lighting.
The
lights
are
operated by
placing
the
PANEL LTS
selector
switch
in the
POST
position
and adjusting
light intensity with
the PANEL
LT rheostat
control knob.
By
placing
the PANEL
LTS
selector switch
in the BOTH
position,
the
post
lights
can
be used
in combination with
the
standard
flood
lighting.
'The
engine instruments,
fuel
quantity
indicators,
radio
equipment,
and
magnetic
compass
have integral
lighting
and operate independently
of
post
or flood
lighting.
Light
intensity of
the
engine
instmments,
fuel
quantity
indicators,
and
radio
lighting is
controlled
by
the RADIO
LT
rheostat
control
knob.
The
integral
compass
light intensity
is
controlled
by
the PANEL
LT rheostat
control
knob.
A cabin
dome
light,
in the
aft
part
of
the
overhead
co4tsole,
is
operated
by
a switch
near the
light. To turn
the
light
on,
move
the
switch
to the right.
A
control
wheel map light
is
arailable and
is
mounted
on
the
bottom of
the
pilotrs
control
wheel.
The
light illuminates
the lower
portion
of
the
cabin
just
forward of the
pilot
and is
helpfuI
when
checking
maps
and
other
flight
data
during
night operations.
To operate the light,
first
turn
on the
NAV LT
switch;
then adjust the map lightrs intensity with
the knurled disk
type
rheostat
control located
at the bottom
of the control
wheel.
A doorpost
map light
is
available,
and
is
located on
the left forward
doorpost.
It
contains
both red and
white
bulbs and
may
be
positioned
to
illuminate
any area desired
by the
pilot.
The light
is controlled by
a
switch,
below
the
light,
which is
labeled RED, OFF,
and
WHITE.
Plac-
ing
the switch
in
the
top
position
will
provide
a red light.
In
the
bot-
tom
position,
standard
white
lighting
is
provided.
In the center
posi-
tion,
the
map light
is turned
off.
The
most
probable
cause
of
a
light
failure is a burned
out bulb; how-
ever,
in the
event
any of the
tighting
systems fail
to illuminate
when
turn-
ed on,
check the appropriate
circuit
breaker. If
the
circuit
breaker has
opened
(white
button
popped
out),
and
there
is no
obvious
indication
of
a
short circuit
(smoke
or
odor),
turn
off
the
light
switch
of
the
affected
lights,
reset
the breaker, and
turn the switch on again.
If
the breaker
opens
again, do not
reset
it.
CABIN
HEATING,
VENTITATING
AND
DEFROSTING
SYSTEM
The temperature
and
volume
of airflow
into
the cabin can be
regulated
to any degree desired
by manipulation
of the
push-pull
CABIN
HT
and
7
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