
SmartKey
Display messages Possible causes/consequences and
M
MSolutions Â
Key Does Not Key Does Not
Belong to Vehicle Belong to Vehicle You have put the wrong SmartKey in the ignition lock.
X
Use the correct SmartKey. Â
Take Take
Your
YourKey
Keyfrom
from
Ignition
Ignition The SmartKey is in the ignition lock.
X
Remove the SmartKey. Â
Obtain a New Key Obtain a New Key The SmartKey needs to be replaced.
X
Visit a qualified specialist workshop. Â
Replace Replace
Key
KeyBattery
Battery The batteries of the KEYLESS-GO key are discharged.
X
Change the batteries (Y page 85).Â
Don't Forget Your Don't Forget Your
Key Key The display message is shown for a maximum of 60 seconds and
is only a reminder.
You have opened the driver's door with the engine switched off.
The KEYLESS-GO key is not in the ignition lock.
X
Remember to take the KEYLESS-GO key with you when you
leave the vehicle. Â
Key Not Detected Key Not Detected
(red display message) The KEYLESS-GO key is not in the vehicle.
A warning tone also sounds.
If the engine is switched off, you can no longer lock the vehicle
centrally or start the engine.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 182).
X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running
because there is interference from a strong source of radio waves.
A warning tone also sounds.
X
Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 182).
X Operate the vehicle with the SmartKey in the ignition lock. 284
Display messagesOn-board computer and displays
ProCarManuals.com

Problem Possible causes/consequences and
M
MSolutions ?
The red coolant
warning lamp lights up
while the engine is
running and the coolant
temperature gauge is
at the start of the scale.
The temperature sensor for the coolant temperature gauge is
defective.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X
Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions. Do not continue
driving under any circumstances.
X Secure the vehicle against rolling away (Y page 182).
X Consult a qualified specialist workshop. Indicator and warning lamps in the instrument cluster
293On-board computer and displays Z
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Problem Possible causes/consequences and
M
MSolutions ?
The red coolant
warning lamp comes on
while the engine is
running.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be
malfunctioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 182).
X Leave the vehicle and keep a safe distance from the vehicle until
the engine has cooled down.
X Check the coolant level and add coolant, observing the warning
notes (Y page 339).
X If you need to add coolant more often than usual, have the
engine coolant system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.
X Do not start the engine again until the coolant temperature is
under 248 ‡(120 †). Otherwise, the engine could be damaged.
X Drive to the nearest qualified specialist workshop.
X Avoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic. ?
The red coolant
warning lamp comes on
while the engine is
running. A warning tone
also sounds.
The coolant temperature has exceeded 248 ‡ (120 †). The
airflow to the engine radiator may be blocked or the coolant level
may be too low.
G WARNING
The engine is not being cooled sufficiently and may be damaged.
Do not drive when your engine is overheated. This can cause some
fluids which may have leaked into the engine compartment to
catch fire.
Steam from the overheated engine can also cause serious burns
which can occur just by opening the hood.
There is a risk of injury.
X Observe the additional display messages in the multifunction
display.
X Pull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 182).294
Indicator and warning lamps in the instrument clusterOn-board computer and displays
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Checking the oil level using the oil
dipstick G
WARNING
Certain components in the engine
compartment, such as the engine, radiator
and parts of the exhaust system, can become
very hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following. Example: vehicles with a gasoline engine
Example: vehicles with a diesel engine
X
Pull oil dipstick :out of the dipstick guide
tube.
X Wipe off oil dipstick :.
X Slowly slide oil dipstick :into the guide
tube to the stop, and take it out again.
If the level is between MIN mark =and
MAX mark ;, the oil level is correct.
X If the oil level has dropped to MIN mark
= or below, add 1.1 US qt (1.0 liter) engine
oil. Adding engine oil G
WARNING
Certain components in the engine
compartment, such as the engine, radiator
and parts of the exhaust system, can become
very hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following. G
WARNING
If engine oil comes into contact with hot
components in the engine compartment, it
may ignite. There is a risk of fire and injury.
Make sure that engine oil is not spilled next
to the filler neck. Let the engine cool down
and thoroughly clean the engine oil off the
components before starting the engine. H
Environmental note
When adding oil, take care not to spill any. If
oil enters the soil or waterways, it is harmful
to the environment.
! Only use engine oils and oil filters that
have been approved for vehicles with a
service system. You can obtain a list of the
engine oils and oil filters tested and
approved in accordance with the
Mercedes-Benz Specifications for Service
Products at any Mercedes-Benz Service
center.
Damage to the engine or exhaust system is
caused by the following:
R using engine oils and oil filters that have
not been specifically approved for the
service system
R replacing engine oil and oil filters after
the interval for replacement specified by
the service system has been exceeded
R using engine oil additives.
! Do not add too much oil. adding too much
engine oil can result in damage to the 338
Engine compartmentMaintenance and care
ProCarManuals.com

engine or to the catalytic converter. Have
excess engine oil siphoned off.
Example: engine oil cap
X
Turn cap :counter-clockwise and remove
it.
X Add engine oil.
If the oil level is at or below the MIN mark
on the oil dipstick, add 1.1 US qt (1.0 l) of
engine oil.
X Replace cap :on the filler neck and turn
clockwise.
Ensure that the cap locks into place
securely.
X Check the oil level again with the oil
dipstick (Y page 338).
Further information on engine oil
(Y page 422). Additional service products
Checking coolant level G
WARNING
Certain components in the engine
compartment, such as the engine, radiator
and parts of the exhaust system, can become
very hot. Working in the engine compartment
poses a risk of injury.
Where possible, let the engine cool down and
touch only the components described in the
following. G
WARNING
The engine cooling system is pressurized,
particularly when the engine is warm. When
opening the cap, you could be scalded by hot
coolant spraying out. There is a risk of injury.
Let the engine cool down before opening the
cap. Wear eye and hand protection when
opening the cap. Open the cap slowly half a
turn to allow pressure to escape. X
Park the vehicle on a level surface.
Only check the coolant level when the
vehicle is on a level surface and the engine
has cooled down.
X Turn the SmartKey to position 2in the
ignition lock (Y page 159).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 159).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
158 ‡ (70 †).
X Turn the SmartKey to position
0 (Y page 159) in the ignition lock.
X Slowly turn cap :half a turn counter-
clockwise to allow excess pressure to
escape.
X Turn cap :further counter-clockwise and
remove it.
If the coolant is at the level of marker bar
= in the filler neck when cold, there is
enough coolant in coolant expansion
tank ;.
If the coolant level is approximately 0.6 in
(1.5 cm) above marker bar =in the fuel Engine compartment
339Maintenance and care Z
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X
Make sure the vehicle is stationary and the
ignition is switched off.
X Turn the SmartKey to position 2in the
ignition lock (Y page 159).
Use the SmartKey instead of the Start/
Stop button on vehicles with KEYLESS-GO.
X Depress and hold the brake pedal.
X Shift the automatic transmission to
position N.
X Release the brake pedal.
X Release the parking brake.
X Switch off the ignition and leave the
SmartKey in the ignition lock.
You can wash the vehicle in an automatic car
wash from the very start.
If the vehicle is very dirty, pre-wash it before
cleaning it in an automatic car wash.
After using an automatic car wash, wipe off
wax from the windshield and the wiper
blades. This will prevent smears and reduce
wiping noises caused by residue on the
windshield.
Washing by hand In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements in all
countries concerned.
X Do not use hot water and do not wash the
vehicle in direct sunlight.
X Use a soft sponge to clean.
X Use a mild cleaning agent, such as a car
shampoo approved by Mercedes-Benz.
X Thoroughly hose down the vehicle with a
gentle jet of water.
X Do not point the water jet directly towards
the air inlet.
X Use plenty of water and rinse out the
sponge frequently.
X Rinse the vehicle with clean water and dry
thoroughly with a chamois.
X Do not let the cleaning agent dry on the
paintwork. When using the vehicle in winter, remove all
traces of road salt deposits carefully and as
soon as possible.
Power washers G
WARNING
The water jet from a circular jet nozzle (dirt
blasters) can cause invisible exterior damage
to the tires or chassis components.
Components damaged in this way may fail
unexpectedly. There is a risk of an accident.
Do not use power washers with circular jet
nozzles to clean the vehicle. Have damaged
tires or chassis components replaced
immediately.
! Always maintain a distance of at least
11.8 in (30 cm) between the vehicle and the
power washer nozzle. Information about
the correct distance is available from the
equipment manufacturer.
Move the power washer nozzle around
when cleaning your vehicle.
Do not aim directly at any of the following:
R tires
R door gaps, roof gaps, joints, etc.
R electrical components
R battery
R connectors
R lights
R seals
R trim
R ventilation slots
Damaged seals or electrical components
can lead to leaks or failures.
! If the SmartKey is within the rear
detection range of KEYLESS-GO, the
following situations, for example, could
lead to the unintentional opening of the
trunk lid/tailgate:
R using a car wash
R using a power washer Care
343Maintenance and care Z
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Vehicles with a collapsible spare wheel
:
Towing eye
; One pair of gloves
= Jack
? Folding wheel chock
A Alignment bolt
B Sheet for faulty wheel
C Tire inflation compressor
D Lug wrench
E Fuse allocation chart
X Open the trunk lid.
X Lift the trunk floor upwards (Y page 312).Flat tire
Preparing the vehicle
Your vehicle may be equipped with:
R MOExtended tires (tires with run-flat
properties) (Y page 354)
Vehicle preparation is not necessary on
vehicles with MOExtended tires.
R a TIREFIT kit (Y page 352)
R an emergency spare wheel(Y page 410)
Information on changing/mounting a wheel
(Y page 395).
X Stop the vehicle on solid, non-slippery and
level ground, as far away as possible from
traffic.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 182). X
If possible, bring the front wheels into the
straight-ahead position.
X Vehicles with AIRMATIC: make sure that
"normal" level is selected (Y page 204).
X Switch off the engine.
X Vehicles without KEYLESS-GO: remove
the SmartKey from the ignition lock.
X Vehicles with KEYLESS-GO: open the
driver's door.
The on-board electronics now have status
0. This is the same as the SmartKey having
been removed.
X Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(Y page 159).
X All occupants must get out of the vehicle.
Make sure that they are not endangered as
they do so.
X Make sure that no one is near the danger
area while a wheel is being changed.
Anyone who is not directly assisting in the
wheel change should, for example, stand
behind the barrier.
X Get out of the vehicle. Pay attention to
traffic conditions when doing so.
X Close the driver's door. MOExtended tires (tires with run-flat
properties)
General notes With MOExtended tires (tires with run flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tires. The affected
tire must not show any clearly visible damage.
You can recognize MOExtended tires by the
MOExtended marking which appears on the
sidewall of the tire. You will find this marking
next to the tire size designation, the load-
bearing capacity and the speed index
(Y page 389).
MOExtended tires may only be used in
conjunction with an active tire pressure loss 354
Flat tireBreakdo
wn assis tance
ProCarManuals.com

warning system or with an active tire pressure
monitor.
If the pressure loss warning message
appears in the multifunction display:
R Observe the instructions in the display
messages ( Ypage 280).
R Check the tire for damage.
R If driving on, observe the following notes.
The maximum driving distance is
approximately 50 miles (80 km) when the
vehicle is partially laden and approximately
18 miles (30 km) when the vehicle is fully
laden.
In addition to the vehicle load, the driving
distance possible depends upon:
R speed
R road condition
R outside temperature
The driving distance possible in run-flat mode
may be reduced by extreme driving
conditions/maneuvers, or it can be increased
through a moderate style of driving.
The maximum permissible distance which
can be driven in run-flat mode is counted from
the moment the tire pressure loss warning
appears in the multifunction display.
You must not exceed a maximum speed of
50 mph (80 km/h).
i When replacing one or all tires, make sure
that you use only tires:
R of the size specified for the vehicle and
R marked "MOExtended"
If a tire has gone flat and cannot be
replaced with a MOExtended tire, a
standard tire may be used as a temporary
measure. Make sure that you use the
proper size and type (summer or winter
tire).
i Vehicles equipped with MOExtended tires
are not equipped with a TIREFIT kit at the
factory. It is therefore recommended that
you additionally equip your vehicle with a
TIREFIT kit if you mount tires that do not feature run-flat properties, e.g. winter tires.
A TIREFIT kit may be obtained from a
qualified specialist workshop.
Important safety notes G
WARNING
When driving in emergency mode, the driving
characteristics deteriorate, e.g. when
cornering, accelerating quickly and when
braking. There is a risk of an accident.
Do not exceed the stated maximum speed.
Avoid abrupt steering and driving maneuvers,
and driving over obstacles (curbs, potholes,
off-road). This applies in particular to a laden
vehicle.
Stop driving in emergency mode if:
R you hear banging noises.
R the vehicle starts to shake.
R you see smoke and smell rubber.
R ESP ®
is intervening constantly.
R there are tears in the sidewalls of the tire.
After driving in emergency mode, have the
wheel rims checked at a qualified specialist
workshop with regard to their further use. The
defective tire must be replaced in every case. TIREFIT kit
Using the TIREFIT kit TIREFIT sticker, 2-part Flat tire
355Breakdown assistance Z
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