139 Controls in detail
Instrument cluster
Coolant temperature indicator
The coolant temperature indicator is on
the right side in the instrument cluster
(
page 28).
Resetting trip odometer
Make sure you are viewing the stan-
dard display in the multifunction dis-
play (
page 147).
If it is not displayed, press buttonè
orÿ on the multifunction steering
wheel repeatedly until the standard dis-
play appears (
page 142).
Press and hold the reset button on the
instrument cluster (
page 138) until
the trip odometer is reset.
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
f r o m t h e e n g i n e i f y o u s e e o r h e a r s t e a m
coming from it.
Stop the vehicle in a safe location away from
other traffic. Turn off the engine, get out of
the vehicle and do not stand near the vehicle
until the engine has cooled down.
!Excessive coolant temperature triggers a
warning in the multifunction display
(
page 406) and the red coolant warning lamp
in the instrument cluster comes on
(
page 383).
The engine should not be operated with the cool-
ant temperature above 248°F (120°C). Doing so
may cause serious engine damage which is not
covered by the Mercedes-Benz Limited
Warranty.
iDuring severe operating conditions, e.g.
stop-and-go traffic, the coolant temperature may
rise close to 248°F (120°C).
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.
319 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.
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).
323 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, let the engine cool off com-
pletely before touching any components on
the vehicle. 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 the ignition is “on” and the engine is
turned manually.
326 Operation
Engine compartment
CLK 63 AMG
1Oil dipstick
2Upper (max) mark
3Lower (min) markTo check the engine oil level with the oil
dipstick, do the following:
Open the hood (page 323).
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 327).
For more information on engine oil, see
“Fuels, coolants, lubricants, etc.”
(
page 489).
For more information on messages in the
multifunction display concerning engine
oil, see the “Practical hints” section
(
page 409).
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).
328 Operation
Engine compartment
Coolant
The engine coolant is a mixture of water
and anticorrosion/antifreeze.
When checking the coolant level,
the vehicle must be parked on level
ground
the coolant temperature must be be-
low 158°F (70°C)
The coolant expansion tank is located on
the passenger side of the engine
compartment.
1Coolant expansion tank
2Cap
Using a rag, turn cap 2 slowly
approximately one half turn counter-
clockwise to release any excess
pressure.
Continue turning the cap 2 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 approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap 2.
More information on coolant can be found
in the “Technical data” section
(
page 494).
Warning!G
In order to avoid 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.
358 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
driven 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.