2004 MERCEDES-BENZ SLK CLASS cooling

46 Getting startedDrivingThe coolant temperature is over 248°F
(120°C)
The coolant is too hot and is no longer
cooling the engine.
Stop the vehicle as soon as possible
and turn off the engine. Allow engine
and coolant to cool down.

Check the coolant level and add cool-
ant if necessary (
page 180).In case of accident
If the vehicle is leaking gasoline:

Do not start the engine under any cir-
cumstances.

Notify local fire and/or police authori-
ties.
If the extent of the damage cannot be de-
termined:

Notify an authorized Mercedes-Benz
Center.
If no damage can be determined on the


major assemblies


fuel system


engine mount

Start the engine in the usual manner.

103 Controls in detail
Climate control
The climate control is operational whenev-
er the engine is running. The system cools
or heats the interior depending on the se-
lected interior temperature and the cur-
rent outside temperature.
Nearly all dust particles, pollutants and
odors are filtered out before outside air en-
ters the passenger compartment through
the air distribution system.
The air conditioning will not engage (no
cooling) if the AC
OFF
mode is selected.
Item
1
Windshield defroster vent
2
Side window defroster vent,
adjustable
3
Thumbwheel for air volume control
for side air vent
4
Side air vent, adjustable
5
Temperature controls for left and
right side passenger compartment
6
Air distribution control
7
Air recirculation/residual heat
8
AC cooling on/off (AC
OFF
)
9
Air volume control
a
Rear window defroster
b
Center air vents, adjustable
c
Thumbwheel for air volume control
for center air vents
iFor draft-free ventilation, move the slid-
ers for the center air ventsb to the
middle position.
Warning
G
When operating the climate control, the air
that enters the passenger compartment
through the air vents in the footwell can be
very hot or very cold (depending on the set
temperature). This may cause burn or frost-
bite to unprotected skin in the immediate
area of the air vents. Always keep sufficient
distance between unprotected parts of the
body and the footwell air vents. If necessary
change the air flow using the air distribution
controls to direct the air away from the foot-
well air vents.Warning!
G
Follow the recommended settings for heat-
ing and cooling given on the following pag-
es. Otherwise the windows could fog up,
impairing visibility and endangering you and
others.

104 Controls in detailClimate control
Setting the temperature
Use temperature controls5 (
page 103)
to separately adjust the air temperature on
each side of the passenger compartment.
You should raise or lower the temperature
setting in small increments, preferably
starting at 72°F (22°C).Increasing

Turn the temperature control5
slightly upwards.
A red marking will be visible and the
climate control system will correspond-
ingly adjust the interior air tempera-
ture.
iThe selected temperature is reached as
quickly as possible.
Severe conditions (e.g. strong air pollu-
tion) may require replacement of the fil-
ter before its scheduled interval. A
clogged filter will reduce the air volume
to the interior.
If the vehicle interior is hot, ventilate
the interior before driving off.
Keep the air intake grille in front of the
windshield free of snow and debris.
iIf you use the standard settings for
heating or cooling the passenger com-
partment (
page 102), you will rarely
need to change the temperature, air
volume or air distribution.

107 Controls in detail
Climate control
Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified. 
Press button± (
page 102).
The indicator lamp on the button±
lights up.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air condition-
ing.

Press button± again (
page 102).
The indicator lamp on the ±button
goes out.
The air conditioning uses the refrigerant
R134a. This refrigerant is free of CFCs
which are harmful to the ozone layer.
Residual heat
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 steering lock to
position1or0, or remove it from the
starter switch.

Press buttonÐ (
page 102).
The indicator lamp on the buttonÐ
comes on.
Warning!
G
While driving, deactivate the air conditioning
only temporarily to prevent window fogging.

180 OperationEngine compartmentBe careful not to spill any oil when adding.
Avoid environmental damage caused by oil
entering the ground or water.
Screw filler cap2 back on filler neck.
More information on engine oil can be
found in the “Technical data” section
(
page 277) and (
page 279).
Transmission fluid level
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the transmission.Coolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze. To check
the coolant level, the vehicle must be
parked on level ground and the engine
must be cool.
The coolant expansion tank is located on
the passenger side of the engine compart-
ment.
!Excess oil must be siphoned or drained
off. It could cause damage to the
engine and catalytic converter not
covered by the Mercedes-Benz Limited
Warranty.
Warning!
G
In order to avoid any possibly serious burns:

Use extreme caution when opening the
hood if there are any signs of steam or
coolant leaking from the cooling system,
or if the coolant temperature gauge indi-
cates that the coolant is overheated.


Do not remove pressure cap on coolant
reservoir if engine temperature is above
194°F (90°C). Allow engine to cool
down before removing cap. The coolant
reservoir contains hot fluid and is under
pressure.


Using a rag, slowly open the cap approx-
imately ½ turn to relieve excess pres-
sure. If opened immediately, scalding
hot fluid and steam will be blown out un-
der pressure.


Do not spill antifreeze on hot engine
parts. Antifreeze contains ethylene gly-
col which may burn if it comes into con-
tact with hot engine parts.


181 Operation
Engine compartment
SLK 230 Kompressor1Coolant expansion tank
2Float in the filler neck
Using a rag, turn the cap to the left to
the first detent position. Allow any ex-
cess pressure to escape.

Continue turning the cap to the left and
remove it.
The coolant level is correct if float2
can be seen at the top through the filler
neck.

Add coolant as required.

Turn the cap back, past the first detent
position, as far as it will go.
More information on coolant can be found
in the “Technical data” section
(
page 281).
SLK 320, SLK 32 AMG1Coolant expansion tank
2Marker in the filler neck
Using a rag, turn the cap slowly approx-
imately one half turn to the left to re-
lease any excess pressure.

Continue turning the cap to the left and
remove it.
iThe drain plugs for the cooling system
are located on the right side of the en-
gine block and at the bottom of the ra-
diator.


182 OperationEngine compartment
The coolant level is correct if the level

for cold coolant: the level must
reach marker2 in the filler neck of
the expansion tank.


for warm coolant: is approx. 0.6 in
(1.5 cm) higher

Add coolant as required.

Replace and tighten cap.More information on coolant can be found
in the “Technical data” section
(
page 281).iThe drain plugs for the cooling system
are located on the right side of the en-
gine block and at the bottom of the ra-
diator.


207 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
The fuel reserve and fuel cap placement
warning lamp:

lights up while driving
The fuel level has gone below the reserve
mark.

Refuel at the next gas station
(page 171).


blinks
The fuel cap is not closed tight.

Check the fuel cap.
A fuel system leak has been detected.

Have the fuel system checked as soon
as possible by an authorized
Mercedes-Benz Center
B
The yellow low engine coolant
level warning lamp remains lit af-
ter starting the engine or lights
up while driving.
The coolant level is too low.

Add coolant (
page 180).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Center.
Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You can be seriously burned.
!Do not ignore the low engine coolant
level warning light. Extended driving
with the light illuminated may cause
serious engine damage not covered by
the Mercedes-Benz Limited Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat, causing major
engine damage.