105 Controls in detail
Locking and unlocking
Important notes on using KEYLESS-GO*
You can also use the SmartKey with
KEYLESS-GO like a normal SmartKey
(
page 100).
You can combine KEYLESS-GO func-
tions with normal SmartKey functions
(e.g. unlocking with KEYLESS-GO and
locking with the‹button).
Always carry the SmartKey with
KEYLESS-GO with you.
Never store the SmartKey with
KEYLESS-GO together with:
Electronic items such as a cellular
phone or another SmartKey with
KEYLESS-GO.
Metallic objects such as coins or
metal foil.
Doing so could impair the function of
the KEYLESS-GO system.
To lock or unlock the vehicle, the
SmartKey with KEYLESS-GO must be
located outside the vehicle within ap-
proximately 3 ft (1 m) of the door to be
opened or the trunk lid.
In order to start the engine with the
SmartKey with KEYLESS-GO:
The SmartKey with KEYLESS-GO
must be located in the vehicle.
All doors must be closed.
The brake pedal must be firmly de-
pressed. Do not depress the accel-
erator.
If the SmartKey with KEYLESS-GO is
positioned farther away from the vehi-
cle, the system may no longer recog-
nize the SmartKey with KEYLESS-GO.
The vehicle then cannot be locked or
the engine started via the KEYLESS-GO
system.
If the SmartKey with KEYLESS-GO is re-
moved from the vehicle (e.g. if passen-
ger exits the vehicle with the SmartKey
with KEYLESS-GO).
iYou can also open and close the windows
(
page 250) and the tilt/sliding sunroof*
(
page 257) or the soft top (page 263) using
the SmartKey with KEYLESS-GO.
!If you can no longer lock or unlock the vehi-
cle with the SmartKey with KEYLESS-GO, then
the batteries in the SmartKey with KEYLESS-GO
are discharged, the SmartKey with KEYLESS-GO
is malfunctioning or the vehicle battery is
drained.
Check the batteries in the SmartKey with
KEYLESS-GO (
page 108) and replace
them if necessary (
page 441).
Use the mechanical key to unlock the driv-
er’s door (
page 427) and the trunk
(
page 428).
Use the mechanical key to lock the driver’s
door (
page 428) and the trunk
(
page 118).
Have the vehicle battery and the battery con-
nections checked (
page 464).
If the SmartKey with KEYLESS-GO is malfunc-
tioning, contact an authorized Mercedes-Benz
Center.
184 Controls in detail
Automatic transmission
Shift to the next higher gear.
The fuel supply will otherwise be inter-
rupted to prevent the engine from over-
revving.
Downshifting
Briefly press the gear selector lever to
the left in theD-direction.
or
Briefly pull left shift paddle1
(
page 181).
The transmission shifts to the next
lower gear.Kickdown
Using the kickdown when driving in the
manual program modeM is not possible.
Deactivating manual shift program
Press the program mode selector
switch (
page 182) repeatedly
until
CorS appears in the multifunction
display.
or
Restart the engine.
The transmission will go to the
automatic program mode (C orS).
The manual program modeM is not
stored.Emergency operation
(Limp-Home Mode)
If vehicle acceleration becomes less re-
sponsive or sluggish or the transmission
no longer shifts, the transmission is most
likely operating in limp-home (emergency
operation) mode. In this mode only second
gear and reverse gear can be selected.
Stop the vehicle in a safe location.
Move the gear selector lever to park
positionP.
Turn off the engine.
Wait at least 10 seconds before
restarting.
Restart the engine.
Move the gear selector lever to
positionD (for second gear) or
positionR.
Have the transmission checked at an
authorized Mercedes-Benz Center as
soon as possible.
Warning!G
On slippery road surfaces, never downshift
in order to obtain braking action. This could
result in drive wheel slip and reduced
vehicle control. Your vehicle’s ABS will not
prevent this type of loss of control.
iWhen you brake or stop, the transmission
shifts down to a gear from which you can easily
accelerate or take off.
198 Controls in detail
Climate control
Air conditioning
The cooling function, is 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 climate
control system. The air in the vehicle will
then no longer be cooled or dehumidified.
Press button2(page 191).
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 condition-
ing.
Press button2(page 191) 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.
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.
311 Operation
Driving instructions
Observe additional messages in the multi-
function display that may appear
(
page 404).
Have the brake system inspected
immediately. Contact an authorized
Mercedes-Benz Center.
All checks and service work on the brake
system should be carried out by qualified
technicians only. Contact an authorized
Mercedes-Benz Center.
Only install brake pads and brake fluid rec-
ommended by Mercedes-Benz.
After hard braking, it is advisable to drive
on for some time, rather than immediately
park, so that the air stream can cool down
the brakes faster.High-performance brake system
(CLK 63 AMG only)
The high-performance brake system is
designed to operate under the extremely
high operating demands required to
accommodate the performance capabili-
ties of the vehicle. The brakes may
produce a squeaking-type noise depending
on the
vehicle speed
brake force applied
ambient conditions, e.g. temperature
and humidity
As with any brake system, the wear of indi-
vidual brake system components such as
brake pads or discs strongly depends on
your driving style and the conditions under
which you operate the vehicle. Thus, a driv-
ing style calling for high demand braking
will cause your vehicle’s brakes to wear
more quickly.
Warning!G
If other than recommended brake pads are
installed, or other than recommended brake
fluid is used, the braking properties of the
vehicle can be degraded to an extent that
safe braking is substantially impaired. This
could result in an accident.
!When driving down long and steep grades,
relieve the load on the brakes by shifting into a
lower gear to use the engine’s braking power.
This helps prevent overheating of the brakes and
reduces brake pad wear.
312 Operation
Driving instructions
Driving off
Apply the brakes to test them briefly after
driving off. Perform this procedure only
when the road is clear of other traffic.
Warm up the engine gradually. Do not
place full load on the engine until the oper-
ating temperature has been reached.Parking
Warning!G
New vehicle brake pads and discs, and
replacement brake pads and discs may take
several hundred miles of driving until they
provide optimum braking efficiency. Until
that time, you may need to use increased
brake pedal pressure while braking. Please
be aware of this and adjust your driving and
braking accordingly during this break-in
period.
Excessive high demand braking will cause
correspondingly high brake wear. Please be
attentive to the brake warning lamp in the
instrument cluster and brake condition mes-
sages in the multifunction display.
Especially for high performance driving, it is
important to maintain and have the brake
system checked regularly.
!When driving off on a slippery surface, do
not allow a drive wheel to spin for an extended
period with the ESP
® switched off. Doing so may
cause serious damage to the drivetrain which is
not covered by the Mercedes-Benz Limited
Warranty.
!Simultaneously depressing the accelerator
pedal and applying the brakes reduces engine
performance and causes premature brake wear
and drivetrain wear.
Warning!G
Do not park this vehicle in areas where com-
bustible materials such as grass, hay or
leaves can come into contact with the hot
exhaust system, as these materials could be
ignited and cause a vehicle fire.
To reduce the risk of personal injury, or
damage to the vehicle or the vehicle
drivetrain, as a result of vehicle movement,
always do the following before turning off
the engine and leaving the vehicle:
Keep right foot firmly on brake pedal.
Firmly depress parking brake pedal.
Move the gear selector lever to
positionP.
Slowly release brake pedal.
When parked on an incline, always turn
the front wheels towards the road curb.
322 Operation
At the gas station
Check regularly and before a long trip
Engine compartment (CLK 550, example)
1Coolant level
2Brake fluid (fuse box cover removed)
3Windshield washer and headlamp
cleaning system*Coolant
For normal replenishing, use water (pota-
ble water quality). For more information,
see “Coolant” (
page 328) and see “Fu-
els, coolants, lubricants, etc.”
(
page 489).
Brake fluid
Removing fuse box cover,
see (
page 473).Windshield washer and headlamp
cleaning system*
For more information on filling up the
washer reservoir, see “Windshield washer
system and headlamp cleaning system*”
(
page 330).
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 325).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
“Replacing bulbs” (
page 443).
For more information, see “Exterior lamp
switch” (
page 55).
Tire inflation pressure
For more information, see “Checking tire
inflation pressure” (
page 341).
iOpening the hood, see (page 323).
!If you find that the brake fluid in the brake
fluid reservoir has fallen to the minimum mark or
below, have the brake system checked for brake
pad thickness and leaks immediately. Notify an
authorized Mercedes-Benz Center immediately.
Do not add brake fluid as this will not solve the
problem. For more information, see also “Practi-
cal hints” (
page 380).
324 Operation
Engine compartment
The hood lock release lever is located to
the left of the steering wheel under the
dashboard.
1Hood lock release lever
Pull lever 1 downwards.
The hood is unlocked.2Lever for opening the hood
Push lever2 under the hood upwards.
Pull up on the hood and then release it.
The hood will be automatically held
open at shoulder height by gas-filled
struts.Closing
Let the hood drop from a height of
approximately 1 ft (30 cm).
The hood will lock audibly.
Check to make sure the hood is fully
closed.
If you can raise the hood at a point
above the headlamps, then it is not
properly closed. Open it again and let it
drop with somewhat greater force.
!To avoid damage to the windshield wipers or
hood, never open the hood if the wiper arms are
folded forward away from the windshield.
Warning!G
When closing the hood, use extreme caution
not to catch hands or fingers.
Be careful that you do not close the hood on
anyone.
Make sure the hood is securely engaged be-
fore driving off. Do not continue driving if the
hood can no longer engage after an acci-
dent, for example. The hood could otherwise
come loose while the vehicle is in motion
and injure you and/or others.