199 Controls in detail
Automatic climate control
Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.
Press button 2 once more
(
page 190).
The indicator lamp on the button
comes on.
The air conditioning uses the refrigerant
R134A. This refrigerant is free of CFCs
which are harmful to the ozone layer.
Residual 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
With the SmartKey:
Turn the SmartKey in the starter switch
to position1 or0, or remove it from
the starter switch.
Press button T (page 190).
The indicator lamp on the button
comes on.
With KEYLESS-GO*:
Turn off the engine by pressing the
KEYLESS-GO* start/stop button and
open the driver’s door (with the driver’s
door open, the starter switch is in posi-
tion 0, same as with the SmartKey re-
moved from the starter switch)
Press button T (page 190).
The indicator lamp on the button
comes on.
!If the 2 button on the automatic climate
control panel starts to flash, this indicates that
the air conditioning is losing refrigerant. The
compressor has turned off. The air conditioning
cannot be turned on again.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Center.
iHow long the system will provide heating
depends on the coolant temperature and the
selected temperature. The blower will run at low
speed regardless of the air distribution control
setting.
446 Technical data
Layout of poly-V-belt drive
SL 550
1Idler pulley
2Idler pulley
3Automatic belt tensioner
4ABC tandem pump (pump for
power-steering assistance and ABC
chassis)
5Air conditioning compressor
6Crankshaft
7Coolant pump
8Generator (alternator)SL 55 AMG
The SL 55 AMG has two poly-V-belts (belt
one shown in purple/belt two shown in
black).
1Idler pulley
2Automatic belt tensioner
3ABC tandem pump (pump for
power-steering assistance and ABC
chassis)
4Air conditioning compressor
5Crankshaft
6Coolant pump
7Generator (alternator)
8Idler pulley
9Automatic belt tensioner
aSupercharger
SL 600, SL 65 AMG
1Automatic belt tensioner
2ABC tandem pump (pump for
power-steering assistance and ABC
chassis)
3Air conditioning compressor
4Crankshaft
5Coolant pump
6Generator (alternator)
7Idler pulley
8Idler pulley
9Idler pulley