
trailer combination carefully, manually
brake using the brake controller, and check
the brakes for correct function.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
R If you couple up a trailer, regularly check
the cargo for secure fastening and make
sure that the trailer lamps and (if
applicable) the trailer brakes are
functioning correctly.
R Bear in mind that the handling will be less
stable when towing a trailer than when
driving without one. Avoid sudden steering
movements.
R The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
R If possible, avoid abrupt braking. Depress
the brake pedal moderately at first, so that
the trailer can activate its own brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission continues to
shift back and forth between two gears
when driving up or downhill, restrict the
shift range. Select shift range 4, 3, 2, or 1.
A lower gear and lower speed reduce the
risk of engine failure.
R When driving downhill, shift to a lower gear
to utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if
installed, the trailer brakes.
R If the coolant temperature increases
dramatically while the air-conditioning
system is switched on, switch off the air-
conditioning system.
Coolant heat can additionally be dissipated
by opening the windows and by setting theblower fan and the interior temperature to
maximum.
R When overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination.
Due to the length of your vehicle/trailer
combination, you will have to travel an
additional distance beyond the vehicle you
are overtaking before returning to the
previous lane.
Decoupling a trailer
GWarning!
Vehicles with AIRMATIC: While you are
coupling or decoupling a trailer, make sure
nobody locks or unlocks the vehicle and/or
opens or closes doors or the tailgate.
The vehicle’s level could change and you
could endanger yourself and/or others as a
result.
Make sure that you do not operate the ADS
switch or the vehicle level control system
when coupling/decoupling the trailer.
XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XClose all doors and the tailgate.XApply the trailer's parking brake.GWarning!
Vehicles with AIRMATIC: As soon as you
disconnect the electrical connection between
the trailer and the vehicle, the vehicle will
lower. To help avoid personal injury, make
sure no one is near the wheel housing or
underneath the vehicle before the electrical
connection is disconnected.
When you decouple the trailer, the vehicle is
temporarily raised because the springs are
relieved of load. Be especially careful during
this process, as you could otherwise injure
yourself and/or others. Make sure that any
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Vehicle equipment
i This manual describes all the standard
and optional equipment of your vehicle
which was available at the time of
purchase. Country-specific differences are
possible. Bear in mind that your vehicle
may not feature all functions described
here. This also refers to safety-related
systems and functions.
Important safety guidelines
You will find an illustration of the instrument
cluster in the "At a glance" section
( Y page 28).
GWarning
A driver's attention to the road and traffic
conditions must always be his/her primary
focus when driving.
For your safety and the safety of others,
selecting features through the multifunction
steering wheel should only be done by the
driver when traffic and road conditions permit
it to be done safely.
Bear in mind that at a speed of just 30 mph
(approximately 50 km/h ), your vehicle is
covering a distance of 44 feet (approximately
14 m) every second.
GWarning!
No messages will be displayed if either the
instrument cluster or the multifunction
display is inoperative.
As a result, you will not be able to see
information about your driving conditions,
such as
R speed
R outside temperature
R warning/indicator lamps
R malfunction/warning messages
R failure of any systems
Driving characteristics may be impaired.
If you must continue to drive, do so with added
caution. Contact an authorized Mercedes-
Benz Center as soon as possible.GWarning
Malfunction and warning messages are only
indicated for certain systems and are
intentionally not very detailed. The
malfunction and warning messages are
simply a reminder with respect to the
operation of certain systems. They do not
replace the owner's and/or driver's
responsibility to maintain the vehicle's
operating safety. Have all required
maintenance and safety checks performed on
the vehicle. Bring the vehicle to an authorized
Mercedes-Benz Center to address the
malfunction and warning messages.
Displays and operation
Tachometer
The red band in the tachometer indicates the
engine's overrevving range.
! Do not drive in the overrevving range, as
this could damage the engine.
The fuel supply is interrupted to protect the
engine when the red band is reached.
Outside temperature display
The outside temperature display is in the
multifunction display.
GWarning!
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges.
Changes in the outside temperature are
displayed after a short delay.
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Display messages
Hiding display messages
GWarning
All categories of messages contain important information which should be taken note of and,
where a malfunction is indicated, addressed as soon as possible at an authorized Mercedes-Benz
Center.
Failure to repair the condition noted may cause damage not covered by the Mercedes-Benz
Limited Warranty, or result in property damage or personal injury.
Display messages appear in the multifunction display.
XPress the V, U , & or * button on the steering wheel to select another display.
or
XPress reset button . on the instrument cluster ( Y page 28).
The display message is cleared.
The multifunction display shows high-priority display messages in red.
You cannot hide display messages of the highest priority. The multifunction display shows
these messages continuously until the causes for the messages have been remedied.
Certain display messages are accompanied by an audible warning tone or a continuous tone.
Please respond in accordance with the display messages and follow the additional notes in
this Operator's Manual.
Message memory menu
The on-board computer saves certain display messages. You can call up the display messages
in the message memory menu.
The message memory menu is only shown if any display messages have been stored.
XPress the V or U button repeatedly, until either the original menu or the message
memory menu is shown.
If there are display messages, the multifunction display shows, for example, 2 messages.XUsing & or * scroll through the display messages.
When the ignition is switched off, all display messages are deleted apart from some high-
priority display messages. Once the causes of the high-priority display messages have been
rectified, the corresponding display messages are also deleted.
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Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Enabled
See Operator's
ManualThe front-passenger air bag is enabled during the journey,
although:
R there is a child, a small adult or an object weighing less than the
system's weight threshold is on the front-passenger seat.
R the front-passenger seat is unoccupied
The system may detect the additional weight of objects on the
seat or forces acting 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 no forces are acting on the seat, such as:
R trapped books, bags, etc. lying on, behind or beside the seat
R head restraints pressing against the headliner
The system may otherwise detect these forces and interpret the
seat occupant's weight as greater than it actually is.XMake sure that the seat is unoccupied and has no objects placed
on it, close the front-passenger door, and switch on the ignition.
Observe the 42 indicator lamps (Y page 42) and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 42 indicator lamp must light up and remain lit.
When the indicator lamp is on, OCS ( Y page 42) has disabled
the front-passenger air bag.
R the display messages Front Passenger Airbag Enabled
See Operator's Manual or Front Passenger Airbag
Disabled See Operator's Manual 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 met, the front-passenger seat can be
occupied again. Whether the 42 indicator lamp
remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not met, the system is not operating correctly.
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Display messagesPossible causes/consequences and M SolutionsFront Passenger
Airbag Disabled
See Operator's
ManualThe front-passenger air bag is disabled 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 weight the system detects may be too low.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.XSet the seat higher ( Y page 100).XMake sure that no objects are exerting force on the seat, e.g.
books, bags, etc. lying under, behind or beside the seat. These
forces may otherwise cause the system to detect too low a
weight and interpret the seat occupant's weight as less than it
actually is.XMake sure that the seat is unoccupied and has no objects placed
on it, close the front-passenger door, and switch on the ignition.
Observe the 42 (Y page 42) indicator lamps and the
multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the 42 indicator lamp must light up and remain lit.
When the indicator lamp is on, OCS ( Y page 42) has disabled
the front-passenger air bag.
R the display messages Front Passenger Airbag Enabled
See Operator's Manual or Front Passenger Airbag
Disabled See Operator's Manual cannot 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 met, the front-passenger seat can be
occupied again. Whether the 42 indicator lamp
remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not met, the system is not operating correctly.
XVisit a qualified specialist workshop immediately.GWarning
If the 42 indicator lamp remains lit with an adult occupant on the front-passenger
seat even after performing the above corrective steps, do not have any passenger use the front-
passenger seat until the system has been repaired.
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Display messagesPossible causes/consequences and M Solutions?
Coolant Stop car,
switch 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 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 OK:
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.
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Driving systemsDisplay messagesPossible causes/consequences and M Solutions°
Vehicle Rising
Wait BrieflyThe vehicle level is too low. XPull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.XWait until the display message disappears before pulling away.°
STOP Car Too LowGRisk of accident
You have pulled away while the vehicle level is still too low or
AIRMATIC is faulty.
AIRMATIC sets the vehicle to the selected level after a short
period. While the display message is displayed:
XMake only slight steering movements. The front fender or the
tires could otherwise be damaged when the steering movement
is too large.XListen for scraping sounds.XDo not drive faster than 50 mph (80 km/h).
If the display message continues to be displayed:
XHave the vehicle checked at a qualified specialist workshop.°
Level Selection
Not PermittedYou cannot change the vehicle level because you are exceeding
the permissible speed for the selected vehicle level.XDrive more slowly and then select the desired vehicle level again
( Y page 183).°
Compressor Cooling
DownYou have selected a higher vehicle level. The compressor first
needs to cool down because of frequent level changes.XDrive in a manner appropriate for the current vehicle level.XMake sure that there is sufficient ground clearance.XAllow the compressor to cool down.
When the compressor has cooled down, the display message
disappears. The vehicle then continues rising to the selected
level.°
MalfunctionAIRMATIC is faulty.XDo not drive faster than 50 mph(80 km/h).XMake sure that there is sufficient ground clearance.XHave the vehicle checked at a qualified specialist workshop.228Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsBlind Spot Assist
Currently
Unavailable See
Operator's ManualBlind Spot Assist is temporarily inoperative if:
R the sensors are dirty.
R its function is impaired due to heavy rain or snow.
R the radar sensor system is outside the operating temperature
range.
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 on-board voltage is too low.
The yellow 9 indicator lamps also light up in the exterior
mirrors.
Blind Spot Assist is operational again and the display message
disappears when:
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 radar sensor system is back within the operating
temperature range.
If the display message continues to be displayed:XClean the sensors ( Y page 287).XRestart the engine.Blind Spot Assist
InoperativeBlind Spot Assist is faulty.
The yellow 9 indicator lamps also light up in the exterior
mirrors.XVisit a qualified specialist workshop.Cruise Control
InoperativeCruise control is faulty. XVisit a qualified specialist workshop.Cruise Control
--- mph A condition for activating cruise control has not been met.
You wanted to save a speed of less than 20 mph (30 km/h).XIf the situation allows, drive faster than 20 mph (30 km/h) and
save the speed.XCheck the activation conditions for cruise control
( Y page 173).DISTRONIC
--- MPH An activation condition for DISTRONIC is not fulfilled.XIf the situation allows, drive faster than 20 mph (30 km/h) and
save the speed.XCheck activation conditions for DISTRONIC ( Y page 175).Display messages229On-board computer and displaysBA 251 USA, CA Edition A 2011; 1; 3, en-USd2sboikeVersion: 3.0.3.52010-04-16T14:31:55+02:00 - Seite 229Z