2003 MERCEDES-BENZ CLK320 CABRIOLET Owner's Manual

206 Driving instructions
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Tire traction
The safe speed on a wet, snow covered or icy road is
always lower than on a dry road.
You should pay particular attention to the condition of
the road whenever the outside temperatures are close to
the freezing point.
We recommend M+S rated radial-ply tires for the winter
season for all four wheels to insure normal balanced
handling characteristics. On packed snow, they can
reduce your stopping distance as compared with
summer tires. Stopping distance, however, is still
considerably greater than when the road is not snow or
ice covered.Tire speed rating
CLK 320:
Your vehicle is factory equipped with “H”-rated tires,
which have a speed rating of 130 mph (210 km/h).
An electronic speed limiter prevents your vehicle from
exceeding a speed of 130 mph (210 km/h).
CLK 320 with Sport Package, CLK 430:
Your vehicle is factory equipped with “W”-rated tires,
which are permissible for speeds up to 168 mph
(270 km/h).
An electronic speed limiter prevents your vehicle from
exceeding a speed of 130 mph (210 km/h).
Despite the tire rating, local speed limits should be
obeyed. Use prudent driving speeds appropriate to
prevailing conditions.
Wa r n i n g !
If ice has formed on the road, tire traction will be
substantially reduced. Under such weather
conditions, drive, steer and brake with extreme
caution.
Wa r n i n g !
Even when permitted by law, never operate a
vehicle at speeds greater than the maximum speed
rating of the tires.

207 Driving instructions
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Use only snow chains that are tested and recommended
by Mercedes-Benz. Your authorized Mercedes-Benz
Center will be glad to advise you on this subject.
Chains should only be used on the rear wheels. Follow
the manufacturer’s mounting instructions.
Snow chains should only be driven on snow covered
roads at speeds not to exceed 30 mph (50 km/h).
Remove chains as soon as possible when driving on
roads without snow.
When driving with snow chains, press the ESP control
switch to OFF, refer to page 218.
Important!
Use of snow chains is not permissible with tire sizes
225 / 45 R17 and 245 / 40 R17.Winter driving instructions
The most important rule for slippery or icy roads is to
drive sensibly and to avoid abrupt acceleration, braking
and steering maneuvers. Do not use the cruise control
system under such conditions.
When the vehicle is in danger of skidding, move
selector lever to position “N”. Try to keep the vehicle
under control by corrective steering action.
Road salts and chemicals can adversely affect braking
efficiency. Increased pedal force may become necessary
to produce the normal brake effect. We therefore
recommend depressing the brake pedal periodically
when traveling at length on salt-strewn roads. This can
bring road salt impaired braking efficiency back to
normal. A prerequisite is, however, that this be done
without endangering other drivers on the road.
Exceeding the maximum speed for which tires are
rated can lead to sudden tire failure causing loss of
vehicle control and resulting in personal injury
and possible death.

208 Driving instructions
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If the vehicle is parked after being driven on salt treated
roads, the braking efficiency should be tested as soon as
possible after driving is resumed while observing the
safety rules in the previous paragraph.Winter driving
Have your vehicle winterized at your authorized
Mercedes-Benz Center before the onset of winter.
•Check engine coolant anticorrosion/antifreeze
concentration.
•Additive for the windshield washer and headlamp
cleaning system: Add MB Concentrate “S” to a
premixed windshield washer solvent/antifreeze
which is formulated for below freezing temperatures
see page 255.
•Test battery: Battery capacity drops with decreasing
ambient temperature. A well charged battery helps
to ensure that the engine can be started, even at low
ambient temperatures.
•Tires: We recommend M+S rated radial-ply tires on
all four wheels for the winter season. Observe
permissible maximum speed for M+S rated
radial-ply tires and the legal speed limit.
In winter operation, the maximum effectiveness of the
antilock brake system (ABS) or of the electronic stability
program (ESP) can only be achieved with M+S rated
radial-ply tires and / or snow chains recommended by
Mercedes-Benz. Snow chains maximize performance.
Wa r n i n g !
If the vehicle becomes stuck in snow, make sure
that snow is kept clear of the exhaust pipe and
from around the vehicle with engine running.
Otherwise, deadly carbon monoxide (CO) gases may
enter vehicle interior resulting in unconsciousness
and death.To assure sufficient fresh air ventilation, open a
window slightly on the side of the vehicle not
facing the wind.

209 Driving instructions
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page 207.
Standing water
Caution!
Do not drive through flooded areas or water of unknown
depth.
If you must dr ive t hrough stand in g water, dr ive slowly to
prevent water from entering the passenger
compartment or the engine compartment. Water in
these areas could cause damage to electrical
components or wiring of the engine or transmission, or
could result in water being ingested by the engine
through the air intake causing severe internal engine
damage. Any such damage is not covered by the
Mercedes-Benz Limited Warranty.
Block heater (Canada only)
The engine is equipped with a block heater.
The electrical cable may be installed at your authorized
Mercedes-Benz Center.Passenger compartment
Traveling abroad
Abroad, there is a widely-spread Mercedes-Benz service
network at your disposal. If you plan to travel into areas
which are not listed in the index of your Mercedes-Benz
Center directory, you should request pertinent
information from your authorized Mercedes-Benz
Center.
Wa r n i n g !
Always fasten items being carried as securely as
possible.In an accident, during hard braking or sudden
maneuvers, loose items will be thrown around
inside the vehicle, and cause injury to vehicle
occupants unless the items are securely fastened in
the vehicle.The trunk is the preferred place to carry objects.

210 Driving systems
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Cruise control
The cruise control allows you to drive in a more relaxed
manner, for example over long distances, as it
automatically maintains the set speed by actively
regulating the throttle setting.
Any given speed above approximately 19 mph
(30 km/h) can be maintained with the cruise control by
operating the lever.1Accelerate and set:
Lift lever briefly to set speed.
Hold lever up to accelerate.
2Decelerate and set:
Depress lever briefly to set speed.
Hold lever down to decelerate.
Normally the vehicle is accelerated to the desired
speed with the accelerator.
Speed is set by briefly pushing the lever to
position 1 or 2. The accelerator can then be
released.
The speed can be increased (e.g. for passing) by
using the accelerator. After the accelerator is
released, the previously set speed will be resumed
automatically.
If a set speed is to be increased or decreased
slightly, e. g. to adapt to the traffic f low, hold lever in
position 1 or 2 until the desired speed is reached, or
briefly tip the lever in the appropriate direction for
increases or decreases in 0.6 mph (1 km/h)
increments. When the lever is released, the newly
set speed remains.
1
4
2
3

211 Driving systems
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To cancel the cruise control, briefly push lever to
position 3.
When you step on the brake pedal or the vehicle
speed drops below approx. 19 mph (30 km/h), for
example when driving upgrade, the cruise control
will be canceled.
If the cruise control cancels by itself and remains
inoperative until the engine is restarted, have the
system checked at your authorized Mercedes-Benz
Center as soon as possible.
4Resume
If the lever is briefly pushed to position 4 when
driving at a speed exceeding approx. 19 mph
(30 km/h), the vehicle resumes the speed which
was set prior to the cancellation of the cruise
control. The last memorized speed is canceled when
the electronic key in the steering lock is turned to
position 1 or 0.Important!
Moving gear selector lever to position “N” switches the
cruise control off.
Wa r n i n g !
Only use the cruise control if the traffic and
weather conditions make it advisable to travel at a
steady speed.• The use of cruise control can be dangerous on
winding roads or in heavy traffic because
conditions do not allow safe driving at a steady
speed.
• The use of cruise control can be dangerous on
slippery roads. Rapid changes in tire adhesion
can result in wheel spin and loss of control.The “Resume” function should only be operated if
the driver is fully aware of the previously set speed
and wishes to resume this particular preset speed.

212 Driving systems
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Notes:
If the engine does not brake the vehicle sufficiently
while driving on a downgrade, the speed you set on the
cruise control may be exceeded. In this case the
automatic transmission shifts down (max. to 3rd gear)
to maintain the set cruise control speed by using the
engine’s braking power.
As soon as the grade eases, the automatic transmission
shifts up again dependent on the selector lever position.
Nevertheless, in some cases you may have to step on the
brake pedal to slow down. In this case the cruise control
is switched off.
Use the lever to resume the previously set speed.Brake assist system (BAS)
The BAS is designed to maximize the vehicle’s braking
capability during emergency braking maneuvers by
having maximum power boost applied to the brakes
more quickly in emergency braking conditions than
might otherwise be afforded solely by the driver’s
braking style. This can help reduce braking distances
over what ordinary driving and braking style might do.
The BAS complements the antilock brake system (ABS).
Wa r n i n g !
BAS cannot prevent the natural laws of physics
from acting on the vehicle, nor can it increase
braking efficiency beyond that afforded by the
condition of the vehicle brakes and tires or the
traction afforded. The BAS cannot prevent
accidents, including those resulting from excessive
speed in turns, following another vehicle too
closely, or aquaplaning. Only a safe, attentive, and
skillful driver can prevent accidents. The
capabilities of a BAS equipped vehicle must never
be exploited in a reckless or dangerous manner
which could jeopardize the user’s safety or the
safety of others.

213 Driving systems
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BAS assistance.
To receive the benefit of the system you must apply
continuous full braking power during the stopping
sequence. Do not reduce brake pedal pressure.
Once the brake pedal is released, the BAS is deactivated.
The malfunction indicator lamp for the electronic
stability program (ESP) is combined with the BAS
malfunction indicator lamp.
The BAS/ESP malfunction indicator lamp in the
instrument cluster comes on with the electronic key in
steering lock position 2 and should go out with the
engine running.
If the BAS/ESP malfunction indicator lamp comes on
permanently while the engine is running, a malfunction
has been detected in either system. As a result, it is
possible that now only partial engine output will be
available. If the BAS malfunctions, the brake system
functions in the usual manner, but without BAS.If the charging voltage falls below 10 volts, the
malfunction indicator lamp comes on and the BAS is
switched off. When the voltage is above this value again,
the malfunction indicator lamp should go out and the
BAS is operational.
With the ABS malfunctioning, the BAS is also switched
off. Both malfunction indicator lamps come on with the
engine running.
If the BAS warning message is displayed, have the BAS
or ESP checked at your authorized Mercedes-Benz
Center as soon as possible.