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288 Operation
Driving instructions
Telephones and two-way radios
Radio transmitters, such as a portable tele-
phone or a citizens band unit should only
be used inside the vehicle if they are con-
nected to an antenna that is installed on
the outside of the vehicle.
Refer to the radio transmitter operation
instructions regarding use of an external
antenna.Catalytic converter
Your Mercedes-Benz is equipped with
monolithic-type catalytic converters, an
important element in conjunction with the
oxygen sensors to achieve substantial
control of the pollutants in the exhaust
emissions. Keep your vehicle in proper
operating condition by following our
recommended maintenance instructions
as outlined in your Maintenance Booklet.
Warning!G
Never operate radio transmitters equipped
with a built-in or attached antenna (i.e. with-
out being connected to an external antenna)
from inside the vehicle while the engine is
running. Doing so could lead to a malfunc-
tion of the vehicle’s electronic system, pos-
sibly resulting in an accident and/or
personal injury.
!To prevent damage to the catalytic
converters, use only premium unleaded gasoline
in this vehicle.
Any noticeable irregularities in engine operation
should be repaired promptly.
Otherwise, excessive unburned fuel may reach
the catalytic converter, causing it to overheat
and potentially start a fire.
Warning!G
As with any vehicle, do not idle, park or op-
erate this vehicle in areas where combusti-
ble 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.
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289 Operation
Driving instructions
Emission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible limits required by law.
These systems, of course, will function
properly only when maintained strictly
according to factory specifications.
Any adjustments on the engine should
therefore only be carried out by qualified
Mercedes-Benz Center authorized techni-
cians.
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
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 possible 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 only with at least one win-
dow 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 and can occur just
by opening the hood. Stay away from
the engine if you see or hear steam com-
ing from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.
Page 291 of 474
290 Operation
Driving instructions
!Excessive coolant temperature triggers a
warning message in the multifunction display
(
page 374).
The engine should not be operated with a
coolant 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 city traffic, the coolant temperature
may rise close to 248°F (120°C).
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291 Operation
At the gas station
At the gas station
Refueling
The fuel filler flap is located on the
right-hand side of the vehicle towards the
rear.
Locking and unlocking the vehicle with the
SmartKey automatically locks and unlocks
the fuel filler flap.1To open fuel filler flap
2To insert fuel filler cap
Remove the SmartKey from the starter
switch.
Open fuel filler flap by pushing at point
indicated by arrow1.
The fuel filler flap springs open.
Turn fuel filler cap counterclockwise
and hold on to it until possible pressure
is released.
Take off fuel filler cap and set it in
direction of arrow2 in the recess on
the inside of fuel filler flap.
To prevent fuel vapors from escaping
into open air, fully insert filler nozzle
unit.
Only fill your tank until the filler nozzle
unit cuts out – do not top off or
overfill.
Replace the fuel filler cap by turning it
clockwise until it audibly engages.
Warning!G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flame or smoking mate-
rials near gasoline!
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and skin contact, extinguish
all smoking materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to
your health.
iIn case that the central locking system does
not release the fuel filler flap, or the opening
mechanism is clamping, contact Roadside
Assistance or an authorized Mercedes-Benz
Center.
Warning!G
Overfilling of the fuel tank may create pres-
sure in the system which could cause a gas
discharge. This could cause the gas to spray
back out when removing the fuel pump noz-
zle, which could cause personal injury.
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292 Operation
At the gas station
Close the fuel filler flap.
Check regularly and before a long trip
Engine compartment
(example illustration, SLK 350)
1Windshield washer system and head-
lamp cleaning system* reservoir
2Brake fluid reservoir
3Coolant expansion tankWindshield washer system and head-
lamp cleaning system*
For information on refilling the reservoir,
see “Windshield washer system and
headlamp cleaning system*”
(
page 301).
Brake fluid
For information on brake fluid, see “Fuels,
coolants, lubricants, etc.” (
page 451).
iMake sure to close the fuel filler flap before
locking your vehicle as the flap locking pin
prevents closing after you have locked the
vehicle.
iOnly use premium unleaded gasoline with a
minimum Posted Octane Rating of 91 (average
of 96 RON/86 MON).
Information on gasoline quality can normally be
found on the fuel pump. Please contact gas
station personnel in case labels on the pump
cannot be found.
For more information on gasoline, see “Premium
unleaded gasoline” (
page 454), refer to the
Factory Approved Service Products pamphlet
(USA only), or contact an authorized
Mercedes-Benz-Center.
iLeaving the engine running and the fuel cap
open can cause the yellow fuel tank reserve
warning lamp to flash and the?malfunction
indicator lamp (USA only) or the
±malfunction indicator lamp (Canada only)
to illuminate.
For more information, see “Practical hints”
(
page 351).
iFor opening the hood, see “Hood”
(
page 294).
!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 “Practical hints”
(
page 350).
Page 294 of 474
293 Operation
At the gas station
Coolant
For normal replenishing, use water
(potable water quality).
For more information on coolant, see
“Coolant level” (
page 300) and “Fuels,
coolants, lubricants, etc.” (
page 451).
Engine oil level
For information on engine oil, see “Engine
oil” (
page 296).Vehicle lighting
Check function and cleanliness.
For more information on vehicle lighting,
see “Replacing bulbs” (
page 400).
For information on switching on the exteri-
or lighting, see “Exterior lamp switch”
(
page 109).
Tire inflation pressure
For information on tire inflation pressure,
see “Important notes on tire inflation
pressure” (
page 313).
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294 Operation
Engine compartment
Hood
Opening
1Hood lock release lever
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 gauge indicates that the engine is
overheated, do not open the hood. Move
away from the vehicle and do not open the
hood until the engine has cooled. If neces-
sary, 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 may 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,
diagnostic socket) of the ignition system
with the engine running
while starting the engine
if ignition is “on” and the engine is
turned manually
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295 Operation
Engine compartment
Pull hood lock release lever1 in direc-
tion of arrow.
The hood is unlocked.
2Lever for opening the hood
Push lever2 on the hood upward to
release hood.
With the hood released, lift the hood by
lifting it at the front edge.
The hood will be automatically held
open at shoulder height by gas-filled
struts.
ClosingLet 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 hand or fingers. Be careful that
you do not close the hood on anyone.
Make sure the hood is securely engaged
before driving. Do not continue driving if the
hood can no longer engage after an accident
for example. The hood could otherwise
come loose while the vehicle is in motion
and injure you and/or others.