
Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Enabled
See Operator's
ManualThe front-passenger air bag is enabled during the journey, even
though:
R a child, a small adult or an object weighing less than the
system's weight threshold is located on the front-passenger
seat.
R the front-passenger seat is unoccupied.
The system may detect objects or forces applying additional
weight on the seat.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XOpen the front-passenger door.XRemove the child and the child restraint system from the front-
passenger seat.XIf necessary, secure the child in a child restraint system on a
suitable rear seat.XMake sure that there are no objects on the seat adding to the
weight.
The system may otherwise detect the additional weight and
interpret the seat occupant's weight as greater than it actually
is.XKeep the seat unoccupied, close the front-passenger door and
switch on the ignition.
Observe the 45(Y page 43) indicator lamp and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45 indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS ( Y page 43) has deactivated the
front-passenger air bag.
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabl'd See
Operator's Manual display messages must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
220Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsXVisit a qualified specialist workshop immediately.GWARNING
If the 45 indicator lamp remains off even after performing the above corrective steps, do
not have any children 12 years old and under and other small individuals use the front-passenger
seat until the system has been repaired.
Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Disabl'd
See Operator's
ManualThe front-passenger air bag is deactivated during the journey even
though an adult or a person larger than a certain size is occupying
the front-passenger seat. If additional forces are applied to the
seat, the system may interpret the occupant's weight as lower
than it actually is.XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XEngage the parking brake.XSwitch off the ignition.XHave the occupant get out of the vehicle.XKeep the seat unoccupied, close the front-passenger door and
switch on the ignition.
Observe the 45(Y page 43) indicator lamp and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 45 indicator lamp must light up and remain lit. When
the indicator lamp is on, OCS ( Y page 43) has deactivated the
front-passenger air bag.
R the Front Passenger Airbag Enabled See Operator's
Manual or Front Passenger Airbag Disabled See
Operator's Manual display messages must not appear in the
multifunction display. Wait for a period of at least 60 seconds
until the necessary system checks have been completed and to
make sure that the display messages do not appear in the
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the 45 indicator lamp remains lit
or goes out depends on how OCS classifies the occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
XVisit a qualified specialist workshop immediately.Display messages221On-board computer and displaysZ

Display messagesPossible causes/consequences and M Solutions?
Coolant Level Low
Stop Vehicle Turn
Engine OffThe coolant is too hot.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.XWait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.XPay attention to the coolant temperature display.XIf the temperature increases again, visit a qualified specialist
workshop immediately.The poly-V-belt may have torn.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XOpen the hood.XCheck whether the poly-V-belt is torn.
If the poly-V-belt is torn:
! Do not continue driving. The engine could otherwise overheat.
XConsult a qualified specialist workshop.
If the poly-V-belt is not damaged:
XWait until the display message disappears before restarting the
engine. Otherwise, there is a risk of engine damage.XPay attention to the coolant temperature display.XVisit a qualified specialist workshop.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.
! If the coolant temperature exceeds 248 ‡(120 †) do not continue driving. The engine will
otherwise be damaged.
226Display messagesOn-board computer and displays

Display messagesPossible causes/consequences and M SolutionsDISTRONIC PLUS
Currently
Unavailable See
Operator's ManualDISTRONIC PLUS is deactivated and is temporarily inoperative if:
R the DISTRONIC PLUS cover in the radiator grill is dirty.
R its function is impaired due to heavy rain or snow.
R the sensors in the bumpers are dirty.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio
stations or other sources of electromagnetic radiation.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
A warning tone also sounds.
DISTRONIC PLUS is operational again and the display message
disappears if:
R the dirt (e.g. slush) drops away while the vehicle is in motion.
R the system detects that the sensors are fully available again.
R the system is within the operating temperature range.
If the display message continues to be displayed:XClean the DISTRONIC PLUS cover in the radiator grill
( Y page 284).XClean the bumpers ( Y page 284).XRestart the engine.DISTRONIC PLUS
InoperativeDISTRONIC PLUS is defective. BAS PLUS (Brake Assist PLUS) and
PRE-SAFE ®
Brake may be inoperative as well.
A warning tone also sounds.XVisit a qualified specialist workshop.DISTRONIC PLUS
OverrideYou have depressed the accelerator pedal. DISTRONIC PLUS is no
longer controlling the speed of the vehicle.XTake your foot off the accelerator pedal.DISTRONIC PLUS
--- mphAn activation condition for DISTRONIC PLUS is not fulfilled.XCheck the activation conditions for DISTRONIC PLUS
( Y page 166).232Display messagesOn-board computer and displays

ProblemPossible causes/consequences and M Solutions?
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.XObserve the additional display messages in the multifunction
display.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.XCheck the coolant level and add coolant (Y page 276). Observe
the warning notes.XIf you need to add coolant more often than usual, have the
engine coolant system checked.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.XAt coolant temperatures under 248 ‡ (120 † ), drive to the next
qualified specialist workshop.XAvoid 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.
The engine is not being cooled sufficiently and may be damaged.XObserve the additional display messages in the multifunction
display.XPull over and stop the vehicle safely and switch off the engine,
paying attention to road and traffic conditions.XAllow the engine and coolant to cool.XCheck the coolant level and add coolant (Y page 276). Observe
the warning notes.XIf you need to add coolant more often than usual, have the
engine coolant system checked.XMake sure that the air supply to the engine radiator is not
blocked, e.g. by snow, slush or ice.XAt coolant temperatures under 248 ‡ (120 † ), drive to the next
qualified specialist workshop.XAvoid subjecting the engine to heavy loads, e.g. driving in
mountainous terrain, and stop-and-go traffic.Warning and indicator lamps in the instrument cluster247On-board computer and displaysZ

not carried out, the system may not be
activated.
If you have questions about the activation,
contact one of the following telephone
assistance services:
R USA: Mercedes-Benz Customer
Assistance Center under
1-800-FOR-MERCedes
(1-800-367-6372) or 1-888-990-9007
R Canada: Customer Service at
1-888-923-8367
An emergency call is dialed automatically if
an air bag or Emergency Tensioning Device is
triggered.
i An mbrace emergency call that has been
initiated automatically cannot be
terminated by the customer.
An emergency call can also be initiated
manually.
As soon as the emergency call has been
initiated, the indicator lamp in the SOS button
flashes. The Connecting Call message
appears on the multifunction display.
The audio output is muted.
Once a connection has been established, the
Call Connected message appears in the
multifunction display.
All important information on the emergency
is transmitted, for example:
R current location of the vehicle (as
determined by the GPS system)
R vehicle identification number
R information on the type of emergency
Shortly after the emergency call has been
initiated, a voice connection is automatically
established between the Mercedes-Benz
Customer Assistance Center and the vehicle
occupants. If the vehicle occupants respond,
the Mercedes-Benz Customer Assistance
Center attempts to get more information on
the emergency.
i If no vehicle occupant answers, an
ambulance is immediately sent to the
vehicle.GWARNING
If the indicator lamp in the SOS button is
flashing continuously and no voice
connection to the Mercedes-Benz Customer
Assistance Center was established, then the
mbrace system could not initiate an
emergency call (e.g. the relevant cellular
phone network is not available).
The message Call Failed appears in the
multifunction display for approximately
10 seconds.
Should this occur, assistance must be
summoned by other means.
Making an emergency call
XTo initiate an emergency call
manually: press cover : briefly to open
it.XPress SOS button ; briefly.
The indicator lamp in SOS button ;
flashes until the emergency call is
concluded.XWait for a voice connection to the
Mercedes-Benz Customer Assistance
Center.XAfter the emergency call is ended, close
cover :.GWARNING
If you feel in any way in jeopardy when in the
vehicle (e.g. smoke or fire in the vehicle,
vehicle in a dangerous road location), please
do not wait for voice contact after you have
pressed the SOS button. Carefully leave the
vehicle and move to a safe location. The
Features263Stowing and featuresZ

Mercedes-Benz Customer Assistance Center
will automatically contact local emergency
officials with the vehicle's approximate
location if they receive an automatic SOS
signal and cannot make voice contact with the
vehicle occupants.
Roadside Assistance buttonXPress and hold Roadside Assistance
button : for more than two seconds.
This initiates a call to the Mercedes-Benz
Customer Assistance Center. The indicator
lamp in Roadside Assistance button :
flashes while the call is active. The
Connecting Call message appears in the
multifunction display. The audio output is
muted.
If a connection can be established, the Call
Connected message appears in the
multifunction display.
If a cellular phone network is available and
there is sufficient GPS reception, the mbrace
system transmits data to the Mercedes-Benz
Customer Assistance Center, for example:
R current location of the vehicle
R vehicle identification number
i The COMAND display shows that an
mbrace call is active. During the call, you
can change to the navigation menu by
pressing the NAVI button on COMAND, for
example.
Voice output is not available.
A voice connection is established between
the Mercedes-Benz Customer Assistance
Center and the vehicle occupants.XDescribe the type of assistance needed.
The Mercedes-Benz Customer Assistance
Center either sends a qualified Mercedes-
Benz technician or organizes for your vehicle
to be transported to the nearest authorized
Mercedes-Benz Center. You may be charged
for services such as repair work and/or
towing. Further details are available in your
mbrace manual.
i The mbrace system failed to initiate a
Roadside Assistance call if:
R the indicator lamp in Roadside
Assistance button : is flashing
continuously.
R no voice connection to the Mercedes-
Benz Customer Assistance Center was
established.
This may be because the corresponding
mobile phone network is not available.
The Call Failed message appears in the
multifunction display.
XTo end a call: press the ~ button on the
multifunction steering wheel.
or
XPress the corresponding button for ending
a phone call on COMAND.
MB Info call button
264FeaturesStowing and features

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops ( Y page 23).
Engine compartment
Hood
Opening the hood
GWARNING
Do not pull the release lever while the vehicle
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.
GWARNING
Do not open the hood when the engine is
overheated. You could be seriously injured.
Observe the coolant temperature gauge to
determine whether the engine may be
overheated. If you see flames or smoke
coming from the engine compartment, move
away from the vehicle. Wait until the engine
has cooled. If necessary, call the fire
department.
GWARNING
There is a risk of injury if the hood is open,
even if the engine is not running.
Some engine components can become very
hot.
To avoid the risk of burns, only touch those
components described in the Operator's
Manual and observe the relevant safety notes.
GWARNING
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.
GWARNING
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:
R with the engine running
R while starting the engine
R when the ignition is switched on and the
engine is turned manually
XMake sure that the windshield wipers are
switched off.GWARNING
The windshield wipers and wiper linkage
could be set in motion.
When the hood is open, you or others could
be injured by the wiper linkage.
Make sure that the windshield wipers are
switched off. Remove the SmartKey or make
sure that no ignition position has been
selected with KEYLESS-GO. All indicator
lamps must be off in the instrument cluster.
274Engine compartmentMaintenance and care