2008 MERCEDES-BENZ CLK550 climate control

210 Controls in detail
Automatic climate control
Air conditioning
The cooling function, only operational
when the engine is running, cools the vehi-
cle interior down to the selected tempera-
ture. The cooling function also
dehumidifies the air in the vehicle interior,
thus preventing the windows from fogging
up.Deactivating
It is possible to deactivate the air condi-
tioning (cooling) function of the automatic
climate control system. The air in the
vehicle will then no longer be cooled or
dehumidified.
Press button2or9
(
page 201).
The indicator lamp on the button goes
out.
The cooling function switches off after
a short delay.Activating
Moist air can fog up the windows. You can
dehumidify the air with the air
conditioning.
Press button2or9
(
page 201) again.
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.
iCondensation may drip out from underneath
the vehicle. This is normal and not an indication
of a malfunction.
Warning!G
If you turn off the cooling function, the
vehicle will not be cooled when weather
conditions are warm. The windows can fog
up more quickly. Window fogging may
impair visibility and endanger you and
others.
!If the air conditioning cannot be turned on
again, this indicates that the air conditioning is
losing refrigerant. The compressor has turned
itself off.
Have the air conditioning checked at the nearest
authorized Mercedes-Benz Center.

211 Controls in detail
Automatic climate control
Residual heat and ventilation*
(Canada only)
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.ActivatingSwitch off the ignition (page 40).
Press button9 (page 201).
The indicator lamp on the button
comes on.Deactivating
Press button9 (page 201).
The indicator lamp on the button goes
out.
The residual heat is automatically turned
off:

when the ignition is switched on

after about 30 minutes

if the battery voltage drops
iHow long the system will provide heating
depends on

the coolant temperature

the temperature set by the operator
The blower will run at speed setting 1 regardless
of the air distribution control setting.

212 Controls in detail
Automatic climate control
Rear passenger compartment
adjustable air vents
The air conditioning for the rear passenger
compartment is controlled via the auto-
matic climate control panel (
page 201).The air vents for the rear passenger
compartment are located in the rear
center console.
1Thumbwheel for air volume control for
center air vents
2Left center air vent
3Right center air ventAdjusting air distribution
Push the slide for the left center
vent2 or right center vent3 to the
left, right, up or down.
The air flow is directed in the corre-
sponding direction.
Adjusting air volume
Turn thumbwheel1 t o t he l e f t o r r i g h t .
The air volume is increased or de-
creased.
iThe temperature at the center air vents2
and3 for the rear passenger compartment
(
page 212) is the same as at the dashboard
center air vents.iFor draft-free ventilation, move the slider for
the center air vents2 and3 upward.

250 Controls in detail
Power windows
Opening and closing the windows
The side windows are opened and closed
electrically. The switches for all the side
windows are on the driver’s door. The
switches for the respective windows are
on the front passenger door and the rear
side trim panels.
1Left front window
2Right front window
3Right rear window
4Left rear window
5Rear window override switch
(
page 88)
Warning!G
When closing the windows, make sure there
is no danger of anyone being harmed by the
closing procedure.
The closing of the door windows can be im-
mediately halted by releasing the switch or,
if switch was pulled past the resistance
point and released, by either pressing or
pulling the respective switch.
The closing of the rear side windows can be
immediately halted by releasing the switch.
The door windows are equipped with the ex-
press-close and automatic reversal func-
tion. If a door window encounters an
obstruction that blocks its path in a circum-
stance where you pulled the switch past the
resistance point and released it to close the
window, the automatic reversal function will
stop the window and open it slightly.
If a door window encounters an obstruction
that blocks its path in a circumstance where
you are closing the window by pulling and
holding the switch, by pressing and holding
button ‹on the SmartKey, by pressing
and holding the lock button (vehicles with
KEYLESS-GO*) on an outside door handle,
CLK cabriolet: by operating the soft top
switch, or by pressing and holding
button, ore on the climate control
panel, the automatic reversal function will
not operate.
When leaving the vehicle, always remove the
SmartKey or SmartKey with KEYLESS-GO*
from the starter switch, take it with you, and
lock the vehicle. Do not leave children unat-
tended in the vehicle, or with access to an
unlocked vehicle. A child’s unsupervised ac-
cess to a vehicle could result in an accident
and/or serious personal injury.

251 Controls in detail
Power windows
Switch on the ignition (page 40).
Opening the windows
Press switch1 to4 to the resistance
point.
The corresponding window will move
downwards until you release the
switch.
Closing the windows
Pull switch1 to4 to the resistance
point.
The corresponding window will move
upwards until you release the switch.Fully opening the door windows
(Express-open)
Press switch1 or2 past the
resistance point and release.
The corresponding window opens
completely.
iYou can also open or close the windows us-
ing the:

SmartKey (summer opening/convenience
feature) (
page 253)

CLK cabriolet: Soft top switch (page 255).
Depending on current position, the windows may
also open or close when:

the air recirculation button, in the con-
trol panel of the climate control
(
page 191) or automatic climate control
(
page 201) is pressed and held
or

the charcoal filter buttone in the control
panel of the automatic climate control
(
page 201) is pressed and held
iOperating the rear side windows from the
rear is not possible if you activate the override
switch (
page 88).
iAfter switching off the ignition (page 38)
or removing the SmartKey from the starter
switch, the power windows can be operated:

until you open a door

for at least 5 minutes if no door was opened
Warning!G
If you pull and hold the switch up when
closing the window, and upward movement
of the window is blocked by some obstruc-
tion including but not limited to arms, hands,
fingers, etc., the automatic reversal will not
operate.

257 Controls in detail
Power tilt/sliding sunroof* (Coupe)
Switch on the ignition (page 40).Opening and closing the power
tilt/sliding sunroof
To open, close, raise, or lower the
tilt/sliding sunroof, move the sunroof
switch to resistance point in the
required direction of arrows1 to4.
Release the sunroof switch when the
tilt/sliding sunroof has reached the
desired position.
Fully opening (Express-open) and
closing (Express-close) the power
tilt/sliding sunroof
To open, close, raise, or lower the
tilt/sliding sunroof, move the sunroof
switch past the resistance point in the
required direction of arrow1 to4
and release.
The tilt/sliding sunroof opens or closes
completely.
!To avoid damaging the seals, do not trans-
port any objects with sharp edges which can
stick out of the tilt/sliding sunroof.
Do not open the tilt/sliding sunroof if there is
snow or ice on the roof, as this could result in
malfunctions.
The tilt/sliding sunroof can be opened or closed
manually should an electrical malfunction occur
(
page 430).
!Please keep in mind that weather conditions
can sometimes change rapidly. Make sure to
close the tilt/sliding sunroof when leaving the
vehicle. If water enters the vehicle interior,
vehicle electronics could be damaged which is
not covered by the Mercedes-Benz Limited
Warranty.
iWhen the tilt/sliding sunroof is open, reso-
nance noises may result in addition to the usual
wind noises. They are caused by minimal pres-
sure changes in the passenger compartment. To
reduce or eliminate these noises, change the po-
sition of the tilt/sliding sunroof or open a side
window slightly.
iYou can also open or close the tilt/sliding
sunroof using the:

SmartKey (summer opening/convenience
feature) (
page 253)
Depending on current position, the tilt/sliding
sunroof may also open or close when:

the air recirculation button, in the con-
trol panel of the climate control
(
page 191) or automatic climate control
(
page 201) is pressed and held
or

the charcoal filter buttone in the control
panel of the automatic climate control
(
page 201) is pressed and held.

356 Operation
Tires and wheels
Uniform Tire Quality Grading Standards
(U.S. vehicles)
Tire manufacturers are required to grade
tires based on three performance
factors: treadwear, traction and
temperature resistance.
1Treadwear
2Traction
3Temperature resistanceQuality grades can be found, where appli-
cable, on the tire sidewall between tread
shoulder and maximum section width. For
example:
All passenger car tires must conform to
federal safety requirements in addition to
these grades.
Treadwear
The treadwear grade is a comparative rat-
ing based on the wear rate of the tire when
tested under controlled conditions on a
specified government test course. For ex-
ample, a tire graded 150 would wear one
and one-half (1
1/2) times as well on the
government course as a tire graded 100.
The relative performance of tires depends
upon the actual conditions of their use,
however, and may depart significantly from the norm due to variations in driving
habits, service practices and differences in
road characteristics and climate.
Traction
The traction grades, from highest to low-
est, are AA, A, B, and C. Those grades rep-
resent the tire’s ability to stop on wet
pavement as measured under controlled
conditions on specified government test
surfaces of asphalt and concrete. A tire
marked C may have poor traction
performance.
iFor illustration purposes only. Actual data
on tires are specific to each vehicle and may vary
from data shown in above illustration.
TreadwearTractionTemperature
200AAA
Warning!G
The traction grade assigned to this tire is
based on straight-ahead braking traction
tests, and does not include acceleration,
cornering, hydroplaning, or peak traction
characteristics.

369 Operation
Vehicle care
Engine cleaning
Prior to cleaning the engine compartment,
make sure to protect electrical
components and connectors from contact
with water and cleaning agents.
Corrosion protection, such as MB Anticor-
rosion Wax, should be applied to the
engine compartment after every engine
cleaning. Before applying, all control
linkage bushings and joints should be
lubricated. The poly-V-belt and all pulleys
should be protected from any wax.
Vehicle washing
In the winter, thoroughly remove all traces
of road salt as soon as possible.
When washing the vehicle underbody, do
not forget to clean the inner sides of the
wheels.Hand-wash
Do not use hot water or wash your vehicle
in direct sunlight.
Only use a mild car wash detergent,
such as Mercedes-Benz approved Car
Shampoo.
Thoroughly spray the vehicle with a
diffused jet of water.
Direct only a very weak spray towards
the ventilation intake.
Use plenty of water and rinse the
sponge and chamois frequently.
Rinse with clean water and thoroughly
dry with a chamois.
Do not allow cleaning agents to dry on
the finish.Automatic car wash
You can have your car washed in an
automatic car wash from the start.
Automatic car washes without brushes are
preferable.
To protect the filter system, switch the
climate control or automatic climate
control to air recirculation mode, see
“Air recirculation” (
page 191) for
climate control or (
page 201) for
automatic climate control.
If the vehicle is very dirty, prewash it
before running it through the automatic
car wash.
iVehicles with KEYLESS-GO*:
If a door handle is hit by a strong jet of water, and
a SmartKey with KEYLESS-GO* is in close
proximity, i.e. within approximately 3 ft
(approximately 1 m), the vehicle could be
inadvertently locked or unlocked.
!Do not use scouring agents on these parts.
Never apply strong force and only use a soft,
non-scratching cloth when cleaning the vehicle.
Do not attempt to wipe the surface with a dry
cloth or sponge.
Otherwise you nay scratch or damage the paint.
!Do not clean your vehicle in an automatic
touchless car wash which uses caustic spray.
Otherwise the caustic spray will damage the
paint, ornamental moldings, or soft top
(CLK cabriolet).