Page 169 of 314

169 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 in-
structions regarding use of an external an-
tenna.
Catalytic converter
Your Mercedes-Benz is equipped with
monolithic type catalytic converters, an
important element in conjunction with the
oxygen sensors to achieve substantial con-
trol of the pollutants in the exhaust emis-
sions. Keep your vehicle in proper
operating condition by following our rec-
ommended maintenance instructions as
outlined in your Service 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 con-
verters, 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 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.
Page 170 of 314

170 OperationDriving instructionsEmission control
Certain engine systems serve to keep the
toxic components of the exhaust gases
within permissible legal limits.
These systems, of course, will function
properly only when maintained strictly ac-
cording to factory specifications. Any ad-
justments on the engine should, therefore,
be carried out only 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
according to Mercedes-Benz servicing re-
quirements. For details refer to the Service
Booklet.
Coolant temperature
During severe operating conditions and
stop-and-go city traffic, the coolant
temperature may rise to approx. 248°F
(120°C).The engine should not be operated with
the coolant temperature over 248°F
(120°C). Doing so may cause serious en-
gine 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, and inhaling it can cause uncon-
sciousness 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 only with at least one win-
dow fully open at all times.
Warning!
G
Driving when your engine is badly over-
heated can cause some fluids, which
may have leaked into the engine com-
partment, to catch fire. You could be se-
riously burned.
Steam from an overheated engine can
cause serious burns and can occur just
by opening the engine 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.
Page 171 of 314

171 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/unlocking the vehicle with
the remote control automatically
locks/unlocks the fuel filler flap.
Fuel filler flap
Remove the key from the steering lock.
Open the fuel filler flap by pushing at
the point indicated by the arrow.
The fuel filler flap springs open.
Turn the fuel cap to the left and hold on
to it until possible pressure is released.
Take off the cap and set it in the recess
on the 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 up or overfill.
Warning!
G
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious inju-
ry. Whenever you are around gasoline, avoid
inhaling fumes and skin contact, extinguish
all smoking materials. Never allow sparks,
flame or smoking materials near gasoline!
Failure to remove the cap slowly could result
in personal injury.
iUse only 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.
More information on gasoline can be
found in the Factory Approved Service
Products pamphlet.
Page 172 of 314

172 OperationAt the gas station
Replace the fuel cap by turning it to the
right.
You will hear when the fuel cap is tight-
ened.
Close the fuel filler flap.
You should hear the latch close shut.
Check regularly and before a long trip
1Windshield washer and headlamp
cleaning system*
More information on filling up the res-
ervoir can be found in the “Operation”
section (
page 184).
2Brake fluid3Coolant level
More information on coolant can be
found in the “Operation” section
(
page 180).
4Engine oil level
More information on engine oil can be
found in the “Operation” section
(page 175).
Opening hood (
page 174).
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.iLeaving the engine running and the fuel
cap open can cause the? lamp to
illuminate.
More information can be found in the
“Practical hints” section (
page 205).
!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. Noti-
fy an authorized Mercedes-Benz Center
immediately. Do not add brake fluid as
this will not solve the problem. For
more information, (
page 204).
Page 173 of 314
173 Operation
At the gas station
Coolant
For normal replenishing, use water (pota-
ble water quality). More information on
coolant can be found in the “Operation”
section (
page 180).
Exterior lamp switch (
page 83).Vehicle lighting
Check function and cleanliness. For infor-
mation on replacing light bulbs, see “Prac-
tical hints” section (
page 226).
Exterior lamp switch (page 83).
Tire inflation pressure
More information on tire inflation pressure
can be found in the “Operation” section
(
page 186).
Page 174 of 314

174 OperationEngine compartment
Engine compartmentHood
Opening
1Hood release
Pull hood release1 downwards.
The hood is unlocked.
2Lever for opening the hood
Push lever2 on the hood upwards.
Open the hood (do not pull up on the
lever) and then release it.
The hood will be automatically held
open at shoulder height by gas-filled
struts.
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.
!To avoid damage to the windshield wip-
ers or hood, never open the hood if the
wiper arms are folded forward away
from the windshield.
Warning!
G
To help prevent personal injury, stay clear of
moving parts when the hood is open and the
engine is running. Make sure the hood is
properly closed before driving. When closing
the hood, use extreme caution not to catch
hands or fingers.
The radiator fan may continue to run for ap-
proximately 30 seconds or even restart af-
ter the engine has been turned off. Stay
clear of fan blades.
Page 175 of 314

175 Operation
Engine compartment
Closing
Let the hood drop from a height of ap-
proximately 1ft (30cm).
The hood will lock audibly.
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.
Engine oil
The amount of oil your engine needs will
depend on a number of factors, including
driving style. Higher oil consumption can
occur when
the vehicle is new
the vehicle is driven frequently at
higher engine speeds
Engine oil consumption checks should only
be made after the vehicle break-in period.
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 vehicle and do not open the hood
until the engine has cooled down. If neces-
sary, call the fire department.Warning!
G
The engine is equipped with a transistorized
ignition system. Because of the high voltage
it is dangerous to touch any components (ig-
nition 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
Warning!
G
Be careful that you do not close the hood on
anyone.
iDo not use any special lubricant addi-
tives, as these may damage the drive
assemblies. Using special additives not
approved by Mercedes-Benz will
restrict your warranty entitlement.
More information on this subject is
available at any authorized Mer-
cedes-Benz Center.
Page 176 of 314

176 OperationEngine compartmentChecking engine oil level via display
(SLK 320, SLK 32 AMG only)
When checking the oil level the vehicle
must
be parked on level ground
be at normal operating temperature
have been stationary for at least five
minutes with the engine turned off
To check the engine oil level via the display
in the speedometer, do the following:
Turn the key in the steering lock to
position2.
1Button
Wait until the symbols: andI
appear in the speedometer display.
Within one second press button1
twice.
One of the following messages will
subsequently appear in the display:
OKThe oil level is correct. Engine oil
does not to be added.
-1.0 Q(Canada:
-1.0 L
)
Add 1.0 quart (Canada:
1.0 liter) of engine oil.
-1.5 Q
(Canada:
-1.5 L
)
Add 1.5 quarts (Canada:
1.5 liters) of engine oil.
-2.0 Q(Canada:
-2.0 L
)
Add 2.0 quarts (Canada:
2.0 liters) of engine oil.For adding engine oil see (
page 179).
More information on engine oil can be
found in the “Technical data” section
(
page 277) and (
page 279).
Other display messages
If there is excess engine oil with the engine
at normal operating temperature, a signal
sounds and the following message will
blink in the display:
HIThe oil level is too high.
Have excess oil siphoned or drained
off. Contact your authorized Mer-
cedes-Benz Center.!If the message
-2.0 Q
(Canada:
-2.0 L
) blinks and a signal
sounds, add oil according to amount
displayed.