
XUsing a rag, slowly open cap :
approximately 1/2 turn counterclockwise
to relieve excess pressure.
XContinue turning cap : counterclockwise
and remove it.
The coolant level is correct if the level
Rfor cold coolant: reaches marking bar
= in coolant expansion tank ;
Rfor warm coolant: is approximately 0.6 in
(1.5 cm) higher
XAdd coolant as required.XScrew cap : back on and tighten it.
For more information on coolant, see the
“Technical data” section (Y page 334) and
(Y page 337).
Washer system and headlamp
cleaning system
GWarning!
Washer solvent/antifreeze is highly
flammable. Do not spill washer solvent/
antifreeze on hot engine parts, because it may
ignite and burn. You could be seriously
burned.
! Always use washer solvent/antifreeze
where temperatures may fall below
freezing point. Failure to do so could result
in damage to the washer system/fluid
reservoir.
! Only use washer fluid which is suitable for
plastic lenses. Improper washer fluid can
damage the plastic lenses of the
headlamps.
! Do not use distilled or deionized water in
the washer fluid reservoir. Otherwise, the
washer fluid level sensor could be
damaged.
Fluid for the washer system, rear window
washer system, and the headlamp cleaning
system is supplied from the washer fluid
reservoir.
During all seasons, use MB Windshield
Washer Concentrate “MB SummerFit”. Mix it
with water or premixed washer solvent/
antifreeze depending on the ambient
temperature (Y page 339).
XOpening washer fluid reservoir: Pull tab
of cap : upwards.
XRefill the washer fluid reservoir.XClosing washer fluid reservoir: Press
cap : onto filler hole until it engages.
For more information, see “Washer system
and headlamp cleaning system”
(Y page 335).
Brake fluid level
! 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. Contact an authorized
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XMake sure the automatic transmission is in
park position P (Y page 103).XEngage the parking brake for the vehicle
( Y page 102).XClose all doors and the tailgate.XAttach the trailer.XPlug in all electrical connectors.
Towing a trailer
There are many different laws, including
speed limit restrictions, having to do with
trailer towing. Make sure your rig will be legal,
not only for where you reside, but also for
where you will be driving. A good source for
this information can be the police or local
authorities.
Note the following, when driving with a trailer:
R In order to gain skill and an understanding
of the vehicle’s behavior, you should
practice turning, stopping and backing up
in an area which is free of traffic.
R Before you start driving check the
- trailer hitch
- break-away switch
- safety chains
- electrical connections
- lighting
- tires
R Adjust the mirrors ( Y page 84) to permit
unobstructed view beyond rear of trailer.
R If the trailer has electric brakes, start your
vehicle and trailer moving slowly, and then
apply only the trailer brake controller by
hand to make sure the brakes are working
properly.
R Always secure items in the trailer to
prevent load shifts while driving.
R When towing a trailer, check occasionally
to make sure the load is secure, and that
trailer lighting and brakes (if so equipped)
are functioning properly.
R Take into consideration that when towing a
trailer, the handling characteristics are
different and less stable from those when
operating the vehicle without a trailer.
It is important to avoid sudden maneuvers.
R The vehicle and trailer combination is
heavier, and therefore limited in
acceleration and climbing ability, and has a
larger braking distance.
It is more prone to reacting to cross wind
gusts, and requires more sensitive steering
input.
R If possible, do not brake abruptly, but
rather engage the brake slightly at first to
permit the trailer to activate its brake. Then
increase the braking force.
! If the trailer should begin to sway, reduce
the vehicle’s speed immediately.
Do not attempt to straighten out the tow
vehicle and trailer by increasing the speed.
R If the transmission shifts between gears on
inclines repeatedly, shift to a lower gear
range manually ( Y page 106). Select 4, 3 ,
2 or 1.
A lower gear and reduction of speed
reduces the chance of engine overloading
and/or overheating.
R When going down an incline, shift into a
lower gear and use the engine’s braking
effect.
Avoid riding the brakes, thus overheating
the vehicle and trailer brakes (if so
equipped).
R If the engine coolant rises to an extremely
high temperature when the air conditioning
is on, turn off the air conditioning system.
Engine coolant heat can be additionally
vented by opening the windows, switching
the climate control fan speed to high and
setting the temperature control to the
maximum.
R During a passing maneuver extreme care
must be exercised since your vehicle with
a trailer will require additional passing248Driving instructionsOperation
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Display messagesPossible causes/consequences and M Solutions?Coolant
Low Stop
Vehicle!
Turn
Engine OffThe coolant is too hot.XStop the vehicle immediately as soon as it is safe to do so.XTurn off the engine immediately.XEngage the parking brake.XOnly start the engine again after the message disappears.
You could otherwise damage the engine.XObserve the coolant temperature gauge in the instrument
cluster.XIf the temperature rises again: Contact an authorized
Mercedes-Benz Center immediately.
During severe operation conditions and stop-and-go city
traffic, the coolant temperature may rise close to 248‡
(120†).
GWarning!
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
engine hood. Stay away from the engine if you see or hear steam 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.
! The engine should not be operated with the coolant temperature above 248‡ (120†).
Doing so may cause serious damage which is not covered by the Mercedes-Benz Limited
Warranty.
280Vehicle status messages in the multifunction displayPractical hints
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Display messagesPossible causes/consequences and M Solutions?Coolant
Low Stop
Vehicle!
Turn
Engine OffThe poly-V-belt could be broken.XStop the vehicle immediately as soon as it is safe to do so.XTurn off the engine immediately.XCheck the poly-V-belt.XIf it is broken: Do not continue to drive. Otherwise the
engine will overheat due to an inoperative water pump
which may result in damage to the engine. Contact an
authorized Mercedes-Benz Center.XIf it is intact: Do not continue to drive the vehicle with this
message displayed. Doing so could result in serious engine
damage that is not covered by the Mercedes-Benz Limited
Warranty.XObserve the coolant temperature gauge in the instrument
cluster.XDrive to the nearest authorized Mercedes-Benz Center
immediately.?The radiator cooling fan is malfunctioning.XObserve the coolant temperature gauge in the instrument
cluster.
If the coolant temperature is below 248‡ (120†), you may
continue driving to an authorized Mercedes-Benz Center.XAvoid placing heavy loads on the engine (e.g. by driving
uphill) as well as stop-and-go traffic.XHave the fan replaced as soon as possible.#The battery is no longer charging.
Possible causes:
R alternator malfunctioning
R broken poly-V-belt
R a malfunction in the electronic systemXStop immediately in a safe location or as soon as it is safe
to do so and check the poly-V-belt.XIf it is broken: Do not continue to drive. Otherwise the
engine will overheat due to an inoperative water pump
which may result in damage to the engine. Contact an
authorized Mercedes-Benz Center.XIf it is intact: Drive to the nearest authorized Mercedes-
Benz Center immediately. Adjust driving to be consistent
with reduced braking responsiveness.Vehicle status messages in the multifunction display281Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 281Z

EngineProblemPossible causes/consequences and M Solutions;
The yellow engine
malfunction indicator
lamp comes on when
the engine is running.There may be a malfunction in
R the fuel management system
R the ignition system
R the emission control system
R systems which affect emissions
Such malfunctions may result in excessive emissions values and
may switch the engine to limp-home (emergency operation) mode.XHave the vehicle checked as soon as possible at an authorized
Mercedes-Benz Center.
i Some states may by law require you to visit a workshop as
soon as the engine malfunction indicator lamp comes on. Check
local requirements.
;
The yellow engine
malfunction indicator
lamp comes on when
the engine is running.A loss of pressure has been detected in the fuel system. The fuel
cap may not be closed properly or the fuel system may be leaky.XCheck the fuel cap ( Y page 212).XIf it is not closed properly: Close the fuel cap.XIf it is closed properly: Have the fuel system checked by an
authorized Mercedes-Benz Center.?The red coolant
temperature
warning lamp
comes on when
the engine is
running.There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently, there is a leak in the
cooling system.
If the coolant level is correct, the electric radiator fan may be
broken.XImmediately add coolant to prevent engine from overheating
( Y page 216).XHave the cooling system checked.XIf the coolant temperature is below 248‡ (120†), you can
continue driving to the nearest authorized Mercedes-Benz
Center.XAvoid high engine loads (e.g. driving uphill) and stop-and-go
driving.What to do if …295Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 295Z

ProblemPossible causes/consequences and M Solutions?The red coolant
temperature
warning lamp
comes on when
the engine is
running and an
acoustic
warning sounds.The coolant temperature has exceeded 248‡ (120†).XStop in a safe location as soon as possible and allow the engine
and coolant to cool down.GWarning!
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 engine hood. Stay away from the engine
if you see or hear steam 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.
! The engine should not be operated with
the coolant temperature above 248‡
(120†). Doing so may cause serious
damage which is not covered by the
Mercedes-Benz Limited Warranty.
Tires
ProblemPossible causes/consequences and M SolutionshCombination
low tire pressure
telltale/TPMS
malfunction
telltale for the
Advanced TPMS
illuminates
continuously.The Advanced TPMS detects a loss of pressure in at least one tire.XCarefully bring the vehicle to a halt, avoiding abrupt steering and
braking maneuvers. Observe the traffic situation around you.XRead and observe messages in the multifunction display
( Y page 262).
If the tire inflation pressure in the respective tire(s) has (have) been
corrected, the combination low tire pressure/TPMS malfunction
telltale goes out after a few minutes of driving.
hCombination
low tire pressure
telltale/TPMS
malfunction
telltale for the
Advanced TPMS
flashes 60
seconds and
then stays
illuminated.There is a malfunction in the Advanced TPMS.XRead and observe messages in the multifunction display
( Y page 262).XHave the Advanced TPMS checked at an authorized Mercedes-
Benz Center.
After the malfunction has been remedied, the combination low tire
pressure/TPMS malfunction telltale goes out after a few minutes
of driving.
296What to do if …Practical hints
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Viscosity grades for engine oils
Using the chart below, select oil viscosity
according to the lowest air temperature
expected before the next oil change.
Engine oil additives
! Do not blend oil additives with engine oil.
They may damage the engine. Damage or
malfunctions resulting from blending oil
additives are not covered by the Mercedes-
Benz Limited Warranty.
Air conditioning refrigerant
R134a (HFC) refrigerant and special PAG
lubricating oil are used in the air conditioning
system.
! Never use R 12 (CFC) or mineral-based
lubricating oil. Otherwise damage to the
system will occur.
Brake fluid
GWarning!
During vehicle operation, the boiling point of
the brake fluid is continuously reduced
through the absorption of moisture from the
atmosphere.
Under extremely strenuous operating
conditions, this moisture content can lead to
the formation of bubbles in the system, thus
reducing the system’s efficiency.
Therefore, the brake fluid must be replaced
regularly. Refer to your vehicle’s Maintenance
Booklet for replacement interval.
Only brake fluid approved by Mercedes-Benz
is recommended. Any authorized Mercedes-
Benz Center will provide you with additional
information.
Premium unleaded gasoline
GWarning!
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline!
Turn off the engine before refueling.
Whenever you are around gasoline, avoid
inhaling fumes and any skin or clothing
contact. Extinguish all smoking materials.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging your
health.
! To maintain the engine’s durability and
performance, premium unleaded gasoline
must be used.
If premium unleaded gasoline is not
available and low octane gasoline is used,
follow these precautions:
RHave the fuel tank only partially filled
with unleaded regular gasoline and fill up
with premium unleaded gasoline as soon
as possible.
RAvoid full throttle driving and abrupt
acceleration.
RDo not exceed an engine speed of
3 000 rpm if the vehicle is loaded with a
light load such as two persons and no
luggage.
RDo not exceed 2/3 of maximum
accelerator pedal position if the vehicle
336Fuels, coolants, lubricants, etc.Technical data
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The coolant solution must be used year round
to provide the necessary corrosion protection
and increase boil-over protection. Refer to
the Maintenance Booklet for replacement
interval.
Coolant system design and coolant used
determine the replacement interval. The
replacement interval published in the
Maintenance Booklet is only applicable if
MB 325.0 Anticorrosion/Antifreeze solution
or other Mercedes-Benz approved products
of equal specification are used to renew the
coolant concentration or bring it back up to
the proper level.
For information on other Mercedes-Benz
approved products of equal specification,
contact an authorized Mercedes-Benz Center
or visit www.mbusa.com (USA only).
To provide important corrosion protection,
the solution must be at least 50%
anticorrosion/antifreeze (equivalent to
freeze protection to approximately -35‡
[-37†]).
If you use a solution that is more than 55%
anticorrosion/antifreeze (freeze protection
to approximately -49‡ [-45†]), the engine
temperature will increase due to the lower
heat transfer capability of the solution.
Therefore, do not use more than this amount
of anticorrosion/antifreeze.
If the coolant level is low, water and MB 325.0
Anticorrosion/Antifreeze should be used tobring it up to the proper level (have cooling
system checked for signs of leakage). Please
make sure the mixture is in accordance with
label instructions.
The water in the cooling system must meet
minimum requirements, which are usually
satisfied by normal drinking water.
If you are not sure about the water quality,
contact an authorized Mercedes-Benz
Center.
Anticorrosion/antifreeze
Your vehicle contains a number of aluminum
parts. The use of aluminum components in
motor vehicle engines necessitates that
anticorrosion/antifreeze coolant used in
such engines be specifically formulated to
protect the aluminum parts. Failure to use
such anticorrosion/antifreeze coolant will
result in a significantly shortened service life.
Therefore, the following product is strongly
recommended for use in your vehicle:
MB 325.0 Anticorrosion/Antifreeze agent.
Before the start of the winter season (or once
a year in hot southern regions), you should
have the anticorrosion/antifreeze
concentration checked.
The coolant is also regularly checked each
time you bring your vehicle to an authorized
Mercedes-Benz Center for service.
ModelApproximate freeze protection-35‡ (-37†)-49‡ (-45†)Cooling systemAll models4.4 US qt (4.2 l)4.9 US qt (4.6 l)338Fuels, coolants, lubricants, etc.Technical data
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