209 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 38).
Press button9 (page 199).
The indicator lamp on the button
comes on.Deactivating
Press button9 (page 199).
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 de-
pends 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.
311 Operation
Driving instructions
Engine adjustments should not be altered
in any way. Moreover, the specified service
jobs must be carried out regularly accord-
ing to Mercedes-Benz servicing require-
ments. For details refer to the
Maintenance Booklet.Coolant temperature
During severe operating conditions and
stop-and-go city traffic, the coolant
temperature may rise close to
approximately 248°F (120°C).
The engine should not be operated with
the coolant temperature over 248°F
(120°C). Doing so may cause serious
engine damage which is not covered by the
Mercedes-Benz Limited Warranty.
Warning!G
Inhalation of exhaust gas is hazardous to
your health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause un-
consciousness and lead to death.
Do not run the engine in confined areas
(such as a garage) which are not properly
ventilated. If you think that exhaust gas
fumes are entering the vehicle while driving,
have the cause determined and corrected
immediately. If you must drive under these
conditions, drive with at least one window
fully open at all times.
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 opening 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.
314 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 320) and see “Fu-
els, coolants, lubricants, etc.”
(
page 472).
Brake fluid
Removing fuse box cover (
page 457).Windshield washer and headlamp
cleaning system*
For more information on filling up the
washer reservoir, see “Windshield washer
system and headlamp cleaning system*”
(
page 322).
Engine oil level
For more information on engine oil, see
“Engine oil” (
page 317).
Vehicle lighting
Check function and cleanliness. For more
information on replacing light bulbs, see
“Replacing bulbs” (
page 427).
For more information, see “Exterior lamp
switch” (
page 54).
Tire inflation pressure
For more information, see “Recommended
tire inflation pressure” (
page 331).
iOpening the hood, see (page 315).
!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 368).
315 Operation
Engine compartment
Engine compartment
Hood Opening
Warning!G
Do not pull the release lever while the vehi-
cle is in motion. Otherwise the hood could
be forced open by passing air flow.
This could cause the hood to come loose
and injure you and/or others.
Warning!G
If you see flames or smoke coming from the
engine compartment, or if the coolant tem-
perature indicator indicates that the engine
is overheated, do not open the hood. Move
away from vehicle and do not open the hood
until the engine has cooled. If necessary,
call the fire department.
Warning!G
You could be injured when the hood is open
- even when the engine is turned off.
Parts of the engine can become very hot. To
prevent burns, only touch owner serviceable
components described in the Operator’s
Manual and comply with all relevant safety
precautions.
Warning!G
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running.
The radiator fan may continue to run for
approximately 30 seconds or even restart
after the engine has been turned off. Stay
clear of fan blades.
Warning!G
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components
(ignition coils, spark plug sockets, diagnos-
tic socket) of the ignition system
with the engine running
while starting the engine
if ignition is “on” and the engine is
turned manually
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.
347 Operation
Tires and wheels
Tire and loading terminology
Accessory weight
The combined weight (in excess of those
standard items which may be replaced) of
automatic transmission, power steering,
power brakes, power windows, power
seats, radio, and heater, to the extent that
these items are available as
factory-installed equipment (whether
installed or not).
Air pressure
The amount of air inside the tire pressing
outward on each square inch of the tire.
Air pressure is expressed in pounds per
square inch (psi), or kilopascal (kPa) or
bars.
Aspect ratio
Dimensional relationship between tire
section height and section width
expressed in percentage.Bar
Another metric unit for air pressure. There
are 14.5038 pounds per square inch (psi)
to 1 bar; there are 100 kilopascals (kPa)
to 1 bar.
Bead
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the
rim.
Cold tire inflation pressure
Tire inflation pressure when your vehicle
has been sitting for at least 3 hours or driv-
en no more than 1 mile (1.6 km).
Curb weight
The weight of a motor vehicle with stan-
dard equipment including the maximum
capacity of fuel, oil, and coolant, and, if so
equipped, air conditioning and additional
optional equipment, but without passen-
gers and cargo.DOT (Department of Transportation)
A tire branding symbol which denotes the
tire meets requirements of the
U.S. Department of Transportation.
GAWR (G
ross Axle Weight Rating)
The GAWR is the maximum permissible
axle weight. The gross vehicle weight on
each axle must never exceed the GAWR for
the front and rear axle indicated on the
certification label located on the driver’s
door B-pillar.
GVW (G
ross Vehicle Weight)
The GVW comprises the weight of the
vehicle including fuel, tools, spare wheel,
installed accessories, passengers and
cargo and, if applicable, trailer tongue
load. The GVW must never exceed the
GVWR indicated on the certification label
located on the driver’s door B-pillar.
356 Operation
Vehicle care
Cleaning and care of vehicle
Regular and proper care will help to
maintain the value of your vehicle. The
best way to protect your vehicle from
harmful environmental influences is to
wash it and use protective treatments reg-
ularly.While in operation, even while parked, your
vehicle is subject to varying external
influences which, if gone unchecked, can
attack the paintwork as well as the vehicle
underbody and cause lasting damage.
Such damage is caused not only by
extreme and varying climatic conditions,
but also by:
Air pollution
Road salt
Tar
Gravel and stone chipping
To avoid paint damage, you should
immediately remove:
Grease and oil
Fuel
Coolant
Brake fluid
Bird droppings
Insects
Tree resins, etc.Frequent washing reduces and / or
eliminates the aggressiveness and
potency of the above adverse influences.
More frequent washings are necessary to
deal with unfavorable conditions:
near the ocean
in industrial areas (smoke, exhaust
emissions)
during winter operation
You should check your vehicle from time to
time for stone chipping or other damage.
Any damage should be repaired as soon as
possible to prevent corrosion.
In doing so, do not neglect the underbody
of the vehicle. A prerequisite for a
thorough check is a washing of the
underbody followed by a thorough
inspection. Damaged areas need to be
re-undercoated.
Your vehicle has been treated at the
factory with a wax-base rustproofing in the
body cavities which will last for the lifetime
of the vehicle. Post-production treatment Warning!G
Many cleaning products can be hazardous.
Some are poisonous, others are flammable.
Always follow the instructions on the
particular container. Always open your
vehicle’s doors or windows when cleaning
the inside.
Never use fluids or solvents that are not
designed for cleaning your vehicle.
Always lock away cleaning products and
keep them out of reach of children.