2003 MERCEDES-BENZ SL500 Ac on off switch

151 Controls in detail
Automatic climate control
Adjusting air distribution
Use the air distribution controls2 and6
(page 148) to separately adjust the air
distribution on each side of the passenger
compartment. The following symbols are
found on the controls:
Adjusting manually

Press the control knob.
The
U
light on the control knob
goes out. The air distribution can be ad-
justed manually.Adjusting automatically

Press the control knob.
The
U
light on the control knob
comes on. The air distribution is adjust-
ed automatically.
Windshield fogged on the outside

Switch the windshield wipers on.

Turn the air distribution control to
h

or
k
.
Maximum cooling MAXCOOL
If the left and right air distribution controls
as well as the airflow volume control are
set to
U
and there is a high need for
cooling, the display MAXCOOL lights up on
the left and right temperature controls.
This provides the fastest possible cooling
of the vehicle interior (when retractable
hardtop is closed).
Defrosting
Activating
Press button
P
(page 148).
The indicator lamp on the button lights
up.
Deactivating

Press button
P
(page 148).
The indicator lamp on the button goes
out. Defrosting is turned off.
Symbol
Function
h
Directs air through the cen-
ter air vents
j
Directs air to the windows
V
Directs air into the entire
vehicle interior
k
Directs air to the footwells
iThese settings should only be selected
for a short time.

152 Controls in detailAutomatic climate controlAir recirculation mode
Switch to air recirculation mode to prevent
unpleasant odors from entering the vehicle
from the outside. This setting cuts off the
intake of outside air and recirculates the
air in the passenger compartment.
Activating
Press button
,
(page 148).
The indicator lamp on the button lights
up.Deactivating

Press button
,
(page 148).
The indicator lamp on the button goes
out.The air recirculation mode is deactivated
automatically


after five minutes if the outside temper-
ature is below approximately 41°F
(5 °C)


after five minutes if the air conditioner
is turned off


after 30 minutes if the outside temper-
ature is above approximately 41°F
(5 °C)
At outside temperatures above 79°F
(26 °C) the system will not automatically
switch back to outside air. A quantity of
outside air is added after approximately
30 minutes.
Warning!
G
When the outside temperature is below
41°F (5°C), only switch to air recirculation
mode for short periods to prevent window
fogging.
iIf you keep button
,
pressed, the
side windows will close.
The air recirculation mode is activated
automatically


at high outside temperatures


if the concentration of carbon mon-
oxide and nitrogen oxide in the out-
side air increases, for example in a
tunnel
If you have turned off the air condition-
er (page 155) or the outside
temperature is below 41°F (5°C), the
air recirculation mode will not switch
on automatically.
iIf you keep button
,
pressed, the
side windows will return to their previ-
ous position.

153 Controls in detail
Automatic climate control
Rear window defroster
The rear window defroster uses a large
amount of power. To keep the battery
drain to a minimum, switch off the defrost-
er as soon as the rear window is clear. The
defroster is automatically deactivated af-
ter approximately 6 to 17 minutes of oper-
ation depending on the outside
temperature.
Activating
Press button
F
(page 148).
The indicator lamp on the button lights
up.Deactivating

Press button
F
(page 148) again.
The indicator lamp on the button goes
out.
Warning!
G
Any accumulation of snow and ice should be
removed from the rear window before driv-
ing. Visibility could otherwise be impaired,
endangering you and others.!The rear window defroster cannot be
switched on when the retractable hard-
top is open. The indicator lamp will
start blinking if the hardtop is open.

Close the retractable hardtop.
The rear window defroster can again be
turned on.
!If the rear window defroster switches
off too soon and the indicator lamp
starts blinking, this means that too
many electrical consumers are operat-
ing simultaneously and there is insuffi-
cient voltage in the battery. The system
responds automatically by deactivating
the rear window defroster.
As soon as the battery has sufficient
voltage, the rear window defroster au-
tomatically turns itself back on.

154 Controls in detailAutomatic climate controlResidual heat and ventilation
With the engine switched off, it is possible
to continue to heat or ventilate the interior
for up to 30 minutes. This feature makes
use of the residual heat produced by the
engine.
Activating
Turn the key in the starter switch to
position1 o r r e m ov e i t f r o m t h e s t a r t e r
switch.

Press button
T
(page 148).
The indicator lamp on button
T

comes on.Deactivating

Press button
T
(page 148).
The indicator lamp on button
T

goes out.
The residual heat is automatically turned
off:


when the ignition is switched on


after about 30 minutes


if the battery voltage dropsDeactivating the automatic climate
control system
Deactivating
It is possible to completely deactivate the
automatic climate control system. 
Press button
M
(page 148).
The indicator lamp on button
M

comes on.
iHow long the system will provide heat-
ing depends on the coolant tempera-
ture and the temperature set by the
operator. The blower will run at speed
setting1 regardless of the air distribu-
tion control setting.
iThis setting is only recommended when
the retractable hardtop is open.

155 Controls in detail
Automatic climate control
Reactivating
There are several ways to reactivate the
automatic climate control system:
Press any button on the automatic cli-
mate control panel (
page 148).
The indicator lamp on button
M

switches off.
or

Turn one of the control knobs on the
automatic climate control.
The indicator lamp on button
M

switches off.
Air conditioning
The air conditioning is operational while
the engine is running and cools the interior
air to the temperature set by the operator.
Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the automatic
climate control system. The air in the vehi-
cle will then no longer be cooled or dehu-
midified.
Press button AC
OFF
(page 148).
The indicator lamp on the
buttonAC
OFF
lights up.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.

Press AC
OFF
again (
page 148).
The indicator lamp on the
buttonAC
OFF
goes out.
The air conditioning uses the refrigerant
R134A. This refrigerant is free of CFCs
which are harmful to the ozone layer.
iCondensation may drip out from under-
neath the vehicle. This is normal and
not an indication of a malfunction.
!If the AC
OFF
button on the automatic
climate control panel starts to blink,
this indicates that the air conditioning
is losing refrigerant. The compressor
has turned itself off. The air condition-
ing cannot be turned on again.


Have the air conditioner checked at
the nearest authorized
Mercedes-Benz Center.

161 Controls in detail
Retractable hardtop

Pull up on the hardtop switch as indi-
cated by the arrow until the hardtop is
completely lowered into its trunk stor-
age compartment and the indicator
lamp in the hardtop switch goes out.
The multifunction display will briefly
show the message
Hardtop open
.Closing the retractable hardtop with
the switch
Before pressing the hardtop switch, you
must make sure that:


the parking brake is engaged
(page 41)


the luggage cover is closed
(page 160)


the trunk lid is closed


the ignition is switched on (key in start-
er switch position2)

Press the hardtop switch as indicated
by the arrow until the hardtop is com-
pletely closed and locked and the indi-
cator lamp in the hardtop switch goes
out.
The multifunction display will briefly
show the message
Hardtop closed
.
iBe sure that the roof is dry before you
open it. Otherwise water may enter the
trunk interior.
Warning!
G
If the retractable hardtop is not fully opened
or closed, a warning will sound after 15 sec-
onds, pressure in the hardtop’s hydraulic
system will drop and the hardtop will lower.
Be sure to keep the hardtop switch pulled or
pressed until the hardtop is fully opened or
closed. The hydraulic pump will then shut
off.
To prevent possible accidents, drive the ve-
hicle only with the hardtop either completely
closed and locked, or fully lowered into its
storage compartment.

163 Controls in detail
Retractable hardtop
Opening the retractable hardtop with
the key

Aim the transmitter eye at the door
handle.

Press and hold button
Œ
until the
retractable hardtop is completely
open.
The seat ventilation switches on. The
rear side windows open. In the tachom-
eter display you will see the message
Hardtop open
.
Warning!
G
If the retractable hardtop does not com-
pletely open or close, the roof hydraulics will
lose pressure and the retractable hardtop is
lowered

after approximately seven minutes
when the ignition is switched on


after approximately 15 seconds when
the ignition is switched off
Shortly before the hardtop is lowered, a
warning will sound and the hardtop switch
lamp will blink. In the speedometer display
you will see
K
, in the tachometer display
you will see the message
being lowered!


Properly lock the retractable hardtop
(page 162) before continuing to drive
Warning!
G
Before operating the switch for the retract-
able hardtop make sure that no persons are
injured by the moving parts (retractable
roof, roof frame, and trunk lid) due to inat-
tention.
Hands must never be placed near the roof
frame, upper windshield area, hardtop, shelf
behind roll bars, or trunk lid while the re-
tractable hardtop is being raised or lowered.
Serious personal injury may occur.
If potential danger exists, release the re-
spective button on the SmartKey. This im-
mediately interrupts the raising or lowering
procedure. You then can operate
Œ
or
‹
to raise or lower the hardtop away
from the danger zone.

164 Controls in detailRetractable hardtopClosing the retractable hardtop with
the key
Aim the transmitter eye at the door
handle.

Press and hold button
‹
until the
retractable hardtop is completely
closed.
The retractable hardtop and the side
windows close. In the tachometer dis-
play you will see the message Hardtop
closed
.Problems when operating the retract-
able hardtop
Indicator lamp in the retractable hard-
top switch is blinking
Several problems may cause the indicator
lamp in the hardtop switch to blink when
activated:


The luggage cover in the trunk is not
closed.
Close the luggage cover in the
trunk.


The trunk lid is open.
Close the trunk lid.


The battery voltage is too low.
Start engine and let run while acti-
vating switch.


The hardtop drive system has shut it-
self down. For safety reasons, no more
than five consecutive attempts may be
made to raise or lower the hardtop.
After about ten minutes you may
again attempt to open or close the
retractable hardtop again.
If the indicator lamp in the retractable
hardtop switch blinks when starting off or
while driving and you hear a warning sound
for a maximum of 10 seconds, the retract-
able hardtop is not locked.

Properly lock the retractable hardtop
(page 162) before continuing to
drive.
If the indicator lamp continues to blink af-
ter you have carried out the above actions,
there is a malfunction.

Have the retractable hardtop system
checked at an authorized
Mercedes-Benz Center.
Warning!
G
If the retractable hardtop does not com-
pletely open or close a warning sounds and
the retractable hardtop switch blinks. In the
speedometer display you will see
K
, in
the tachometer display you will see the mes-
sage
being lowered!
. After about
15 seconds the roof hydraulics lose pres-
sure.
Properly lock the retractable hardtop
(
page 162) before continuing to drive.