316 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 lever 2 on 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 that the hood is securely en-
gaged before driving off. Do not continue
driving if the hood can no longer engage af-
ter an accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and injure you and/or others.
318 Operation
Engine compartment
CLK 350 / CLK 550
1Oil dipstick
2Upper (max) mark
3Lower (min) mark
CLK 63 AMG
1Oil dipstick
2Upper (max) mark
3Lower (min) mark
To check the engine oil level with the oil
dipstick, do the following:
Open the hood (page 315).
Pull out oil dipstick1.
Wipe oil dipstick1 clean.
Fully insert oil dipstick1 into the
dipstick guide tube.
Pull out oil dipstick1 again after
approximately 3 seconds to obtain ac-
curate reading.
The oil level is correct when it is be-
tween the lower (min) mark3 and
upper (max) mark2 of oil dipstick1.
If necessary, add engine oil.
For adding engine oil, see “Adding en-
gine oil” (
page 319).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 472).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 394).
iCLK 350:
The filling quantity between the upper and lower
marks on the oil dipstick is approximately
2.1 US qt. (2.0 l).
CLK 550 / CLK 63 AMG:
The filling quantity between the upper and lower
marks on the oil dipstick is approximately
1.6 US qt. (1.5 l).
320 Operation
Engine compartment
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
compartment.
1Coolant expansion tank
2CapUsing a rag, turn cap2 slowly
approximately one half turn counter-
clockwise to release any excess pres-
sure.
Continue turning the cap2 counter-
clockwise and remove it.
The coolant level is correct if the level
for cold coolant: reaches the marking
(plastic bridge) inside the reservoir
for warm coolant: is approx. 0.6 in
(1.5 cm) higher
Add coolant as required.
Replace and tighten cap2.
More information on coolant can be found
in the “Technical data” section
(
page 477).
Warning!G
In order to avoid any potentially 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 indicator
indicates that the coolant is overheated.
Do not remove pressure cap on coolant
reservoir if the coolant temperature is
above 158°F (70°C). Allow the coolant
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 1/2 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.
362 Operation
Vehicle care
Cleaning the windows and the wiper
blades
Make sure the hood is fully closed.
Make sure the vehicle’s on-board
electronics have status0 (
page 36).
Fold the wiper arms forward until they
snap into place.
Clean the wiper blade inserts with a
clean cloth and detergent solution.
Use a soft, clean cloth and a mild
window cleaning solution on all outside
and inside glass surfaces.
An automotive glass cleaner is
recommended.Light alloy wheels
If possible, clean wheels once a week.Use Mercedes-Benz approved Wheel
Care, a soft bristle brush and a strong
spray of water for cleaning the light
alloy wheels.!Never open the hood when the wiper arms
are folded forward.
Warning!G
For safety reasons, switch off wipers and
remove SmartKey from starter switch
(vehicles with KEYLESS-GO*: Make sure the
vehicle's on-board electronics have
status0) before cleaning the windshield
and/or the wiper blades. Otherwise, the
wiper motor could suddenly turn on and
cause injury.
!Do not pull on the wiper blade inserts. They
could tear.
!Fold the windshield wiper arms back onto
the windshield before turning the SmartKey in
the starter switch or pressing the KEYLESS-GO
start/stop button (vehicles with KEYLESS-GO*).
Hold on to the wiper when folding the wiper arm
back. If released, the force of the impact from
the tensioning spring could crack the windshield.
!To clean the window interior, do not use a
dry cloth, abrasives, solvents or cleaners
containing solvents. Do not touch the inside of
the front, rear or side windows with hard objects
such as an ice scraper or ring. Doing so may
damage the windows.
!Only use acid-free cleaning materials. Acid
may cause corrosion or damage the clear coat.
!The vehicle should not be parked for an
extended period of time immediately after it has
been cleaned, especially not after the wheel rims
have been cleaned with wheel rim cleaner.
Wheel rim cleaners can lead to increased
corrosion of the brake disks and brake pads.
Non-approved wheel cleaners may also damage
the wheel paint if the car is not driven after
cleaning. Therefore, the vehicle’s brake system
should always be warmed-up before it is parked
after cleaning. To do so, please drive your vehicle
for several minutes to allow the brakes to dry.
When applying Mercedes-Benz approved Tire
Care and Mercedes-Benz approved Wheel Care
products, take care not to spray them on the
brake disks.
371 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
•The red coolant warning lamp
comes on when the engine is
running.There is insufficient coolant in the reservoir.Add coolant to prevent engine from
overheating (
page 320).
If this warning lamp comes on frequently,
there is a leak in the cooling system.Have the cooling system checked.
If the coolant level is correct, the electric ra-
diator fan may be broken.If the coolant temperature is below
257 °F (125 °C), you can continue
driving to the nearest authorized
Mercedes-Benz Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.
•The red coolant warning lamp
comes on while driving and you
hear a warning sound.The coolant temperature has exceeded
257 °F (125 °C).Stop as soon as possible and allow
the engine and coolant to cool down.
Warning!G
Driving when your engine is overheated can
cause some fluids which may have leaked
into the engine compartment to catch fire.
You could be seriously burned.
Steam from an overheated engine can cause
serious burns which can occur just by open-
ing the hood. Stay away from the engine if
you see or hear steam coming from it.Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
392 Practical hints
What to do if …?
During severe operating conditions and
stop-and-go city traffic, the coolant tem-
perature may rise close to 248°F (120°C).
Display symbolDisplay messagePossible cause/consequencePossible solution
Observe the coolant temperature indicator in
the instrument cluster (
page 26).
If the temperature rises again:
Contact an authorized Mercedes-Benz
Center immediately.
•The cooling fan for the coolant is mal-
functioning.Observe the coolant temperature indicator in the
instrument cluster (
page 26).
Have the fan replaced as soon as possible.
Warning!G
Driving when your engine is overheated can
cause some fluids which may have leaked
into the engine compartment to catch fire.
You could be seriously burned.
Steam from an overheated engine can cause
serious burns which can occur just by open-
ing the hood. Stay away from the engine if
you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.!The engine should not be operated with the
coolant temperature above 248°F (120°C). Do-
ing so may cause serious engine damage which
is not covered by the Mercedes-Benz Limited
Warranty.
430 Practical hints
Replacing bulbs
Replacing bulbs for front lamps
Before you start to replace a bulb for a
front lamp, do the following first:
Turn the exterior lamp switch to
positionM (
page 126).
Open the hood (page 315).
Front lamps halogen-type
1Housing cover for low beam headlamp
2Housing cover for high beam head-
lamp, parking and standing lamp3Bulb socket for turn signal lamp bulb
4Bulb holder of low beam bulb
5Bulb holder of high beam bulb
6Bulb socket for parking and standing
lamp bulb
Low beam bulb
Turn housing cover1 counterclock-
wise and remove it.
Turn bulb holder4 with the bulb coun-
terclockwise and remove it.
Pull the bulb at its socket out of bulb
holder4.
Insert the new bulb so that its socket
locates in the recess of bulb holder4
and is level to it.
Reinsert bulb holder4 with the bulb in
the lamp and turn clockwise.
Align housing cover1 and turn it
clockwise.
High beam bulb
Turn housing cover2 counterclock-
wise and remove it.
Turn bulb holder5 with the bulb coun-
terclockwise and remove it.
Pull the bulb at its socket out of bulb
holder5.
Insert the new bulb so that its socket
locates in the recess of bulb holder5
and is level to it.
Reinsert bulb holder5 with the bulb in
the lamp and turn clockwise.
Align housing cover2 and turn it
clockwise.
434 Practical hints
Replacing wiper blades
Removing and installing wiper blades
Remove SmartKey from starter switch
(vehicles with KEYLESS-GO*: make
sure the vehicle's on board electronics
have status 0).
Removing wiper blades
1Unlocking
2Tab
Pull the tab2 in the direction of
arrow1.
The wiper blade is unlocked.
Lift up the wiper arm as far as you need
to remove the wiper blade.
Carefully fold the wiper arm back to
rest on the windshield.
Warning!G
For safety reasons, switch off wipers and
remove SmartKey from starter switch
(vehicles with KEYLESS-GO*: make sure the
vehicle’s on-board electronics have
status0) before replacing a wiper blade.
Otherwise, the wiper motor could suddenly
turn on and cause injury.
Warning!G
Wiper blades are components that are sub-
ject to wear and tear. Change the wiper
blades twice a year, preferably in the spring
and fall. Otherwise the windows will not be
properly wiped. As a result, you may not be
able to observe surrounding traffic condi-
tions and could cause an accident.
!Never open the hood when the wiper arms
are folded forward.
For your convenience, we recommend that you
have this work carried out by an authorized
Mercedes-Benz Center.
!Do not pull on the wiper blade inserts. They
could tear.
!Hold on to the wiper arm. If released, the
force of the impact from the tensioning spring
could crack the windshield.