Page 314 of 481

313 Operation
Engine compartment
Transmission fluid level*
Vehicles with automatic transmission*:
The transmission fluid level does not need
to be checked. If you notice transmission
fluid loss or gear shifting malfunctions,
have an authorized Mercedes-Benz Center
check the transmission.
Coolant level
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.Warning!
G
In order to avoid any possibly 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 gauge indi-
cates that the coolant is overheated.
Do not remove pressure cap on coolant
reservoir if coolant temperature is
above 158°F (70°C). Allow engine 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 ½ 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
glycol which may burn if it comes into
contact with hot engine parts.
Page 315 of 481

314 OperationEngine compartmentThe coolant expansion tank is located on
the passenger side of the engine compart-
ment.SLK 350 (example)1Coolant expansion tank
2Cap
3Marking bar in the expansion tank
Using a rag, turn cap2 slowly approx-
imately one half turn counterclockwise
to release any excess pressure.
Continue turning cap2 counterclock-
wise and remove it.
The coolant level is correct if the level
for cold coolant: reaches marking
bar3 in expansion tank1
for warm coolant: is approximately
0.6 in (1.5 cm) higher
Add coolant as required.
Replace and tighten cap2.
For more information on coolant, see
“Coolants” (
page 453).
Battery
Your vehicle’s battery is located in the en-
gine compartment.
The battery should always be sufficiently
charged in order to achieve its rated ser-
vice life. Refer to the Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to
have the battery charge checked more
frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Center about
steps you need to observe.
Page 316 of 481

315 Operation
Engine compartment
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.Windshield washer system and
headlamp cleaning system*
The windshield washer reservoir is located
on the passenger side of the engine com-
partment.SLK 350 (example)1Washer fluid reservoir cap
Fluid for the windshield washer system and
the headlamp cleaning system* is supplied
from the windshield washer reservoir. It
has a capacity of approx. 7.4 US qt (7 l).
G
Observe all safety instructions
and precautions when handling
automotive batteries.
A
Risk of explosion
D
Keep flames or sparks away
from battery. Do not smoke.
B
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
In case it does, immediately
flush affected area with clean
water and seek medical help if
necessary.
E
Wear eye protection.
C
Keep children away.
F
Follow the instructions in this
Operator's Manual.
Page 317 of 481

316 OperationEngine compartmentDuring all seasons, add MB Windshield
Washer Concentrate “S” to water. Premix
the windshield washer fluid in a suitable
container.
Pull cap upward using latch until it
opens.
Refill the reservoir with MB Windshield
Washer Concentrate and water (or
commercially available premixed wind-
shield washer solvent/antifreeze, de-
pending on ambient temperatures).
Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could re-
sult in damage to the washer sys-
tem/reservoir.
Push cap down until it engages.For more information, see “Windshield
washer system and headlamp cleaning
system*” (
page 456).
Warning!
G
Washer solvent/antifreeze is highly flamma-
ble. Do not spill washer solvent/antifreeze
on hot engine parts, because it may ignite
and burn. You could be seriously burned.
!Only use washer fluid which is suitable
for plastic lenses. Improper washer flu-
id can damage the plastic lenses of the
headlamps.
Page 349 of 481

348 OperationWinter drivingBefore the onset of winter, have your
vehicle winterized at an authorized
Mercedes-Benz Center. This service
includes:
Checking anticorrosion and antifreeze
concentration.
Adding of cleaning concentrate to the
water of the windshield and headlamp
cleaning* system. Add
MB Concentrate “S” to a pre-mixed
windshield washer solvent/antifreeze
which is formulated for temperatures
below freezing point (
page 456).
Battery test. Battery capacity drops
with decreasing ambient temperature.
A well charged battery helps to make
sure the engine can be started, even at
low ambient temperatures.
Tire change.
Winter tires
Always use winter tires at temperatures
below 45°F (7°C) and whenever wintry
road conditions prevail. Not all M+S rated
tires provide special winter performance.
Make sure the tires you use show M+S and
the mountain/snowflake.marking on
the tire sidewall. These tires meet specific
snow traction performance requirements
of the Rubber Manufacturers Association
(RMA) and the Rubber Association of Can-
ada (RAC) and have been designed specif-
ically for use in snow conditions. Using
winter tires is the only way to achieve the
maximum effectiveness of the ABS and
ESP
® in winter operation.For safe handling, make sure all mounted
winter tires are of the same make and have
the same tread design.
Always observe the speed rating of the
winter tires mounted to your vehicle. If the
maximum speed for which your tires are
rated is below the speed rating of your ve-
hicle, you must place a notice to this effect
where it will be seen by the driver. Such no-
tices are available at your tire dealer or any
authorized Mercedes-Benz Center.!When scraping ice or snow from the
rear window, be careful not to damage
the sealing strip or apertures along the
side of the window.
Warning!
G
Winter tires with a tread depth under
1/6 in
(4 mm) must be replaced. They are no long-
er suitable for winter operation.
Page 351 of 481

350 OperationMaintenanceIn the “Operation” section you will find de-
tailed information on operating, maintain-
ing, and caring for your vehicle.
We strongly recommend that you have
your vehicle serviced by an authorized
Mercedes-Benz Center, in accordance with
the Maintenance Booklet at the times
called for by the maintenance service indi-
cator display.
Failure to have the vehicle maintained in
accordance with the Maintenance Booklet
and maintenance service indicator at the
designated times/mileage will result in ve-
hicle damage not covered by the
Mercedes-Benz Limited Warranty.
The maintenance service indicator will no-
tify you when your next maintenance ser-
vice is due.
Starting approximately one month before
maintenance service is due, one of the fol-
lowing messages will appear in the multi-
function display while you are driving or
when you switch on the ignition (example
service A):
Service A in XXXXX miles (km)
Service A in XXX days
Service A in X day
Carry out service AThe maintenance services will be indicated
by showing a service type A through
type H in the multifunction display.
Types A through H are classified based on
estimated time needed to perform the
maintenance service, ranging:
from
Service A(approx. 1 hour)
toService H(approx. 8 hours)
iVehicles equipped with FSS PLUS
(Flexible S
ervice S
ystem PLUS) only
(Canada vehicles): The interval be-
tween maintenance services depends
on your driving habits. A gentle driving
style, moderate engine speeds and the
avoidance of short-distance trips will
lengthen the interval between mainte-
nance services.
Page 353 of 481

352 OperationMaintenance
Resetting the maintenance service indicator
In the event that the maintenance service
on your vehicle is not carried out by an au-
thorized Mercedes-Benz Center, you can
have the maintenance service indicator re-
set. The automotive maintenance facility
carrying out the maintenance service will
find the information for resetting the main-
tenance service indicator in the mainte-
nance-relevant information for your
vehicle. Such information is available from
either your authorized Mercedes-Benz
Center or directly from Mercedes-Benz.
iIf the battery is disconnected, the days
of disconnection will not be included in
the count shown by the maintenance
service indicator. To arrive at the true
maintenance service deadline, you will
need to subtract these days from the
days shown in the maintenance service
indicator.
Do not confuse the maintenance ser-
vice indicator with the engine oil level
indicatorN.
iIf the maintenance service indicator
was inadvertently reset, have an autho-
rized Mercedes-Benz Center correct it.
Only reset if the proper maintenance
service has been performed. Resetting
the system without performing the
proper maintenance service as called
for by the maintenance service indica-
tor will result in engine damage and/or
other vehicle damage not covered by
the Mercedes-Benz Limited Warranty.
Page 356 of 481

355 Operation
Vehicle care
Paintwork, painted body components
Mercedes-Benz approved Paint Care
should be applied when water drops on the
paint surface do not “bead up”. This should
normally be done every 3 to 5 months, de-
pending on the climate and washing deter-
gent used.
Mercedes-Benz approved Paint Cleaner
should be applied if the paint surface
shows signs of embedded dirt (i.e. loss of
gloss).
Do not apply any of these products or wax
if your vehicle is parked in the sun or if the
hood is still hot.
Use the appropriate MB-Touch-Up
Stick for quick and provisional repairs
of minor paint damage (i.e. chips from
stones, vehicle doors, etc.).Engine cleaning
Prior to cleaning the engine compartment,
make sure to protect electrical compo-
nents and connectors from the intrusion of
water and cleaning agents.
Corrosion protection, such as
MB Anticorrosion Wax should be applied to
the engine compartment after every en-
gine cleaning. Before applying, all control
linkage bushings and joints should be lu-
bricated. The poly-V-belt and all pulleys
should be protected from any wax.Vehicle washing
In the winter, thoroughly remove all traces
of road salt as soon as possible.
Hand-wash
Do not use hot water or wash your vehicle
in direct sunlight.
Use only a mild car wash detergent,
such as Mercedes-Benz approved Car
Shampoo.
Thoroughly spray the vehicle with a dif-
fused jet of water.
Direct only a very weak spray towards
the ventilation intake.
Use plenty of water and rinse the
sponge and chamois frequently.
Rinse with clean water and thoroughly
dry with a chamois.
Do not allow cleaning agents to dry on
the finish.
!Affixing stickers, adhesive tape or sim-
ilar materials to painted body compo-
nents may damage the paintwork.