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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persons remaining in the vehicle do not press
the switches for vehicle level control or the
ADS.XDetach the trailer cable and decouple the
trailer.XDetach the trailer cable and decouple the
trailer.XSwitch off the engine.
Permissible trailer load and drawbar
noseweight
Weight specifications
The Gross Trailer Weight (GTW) is the
combined weight of the trailer together with
the cargo and equipment loaded on the
trailer. Permissible gross weight: 3500 lb
(1588 kg).
The permissible Trailer drawbar Weight
Rating (TWR) is the maximum weight
permitted on the trailer drawbar: 350 lb
(158 kg) limit for Mercedes-Benz-approved
trailer couplings.
Loading a trailer
R When loading a trailer, please note that
neither the permissible gross trailer weight
nor the permissible Gross Vehicle Weight
Rating (GVWR) may be exceeded. The
permissible Gross Vehicle Weight Rating
(GVWR) is specified on the type plate
located on the B-pillar on the driver's side
of your vehicle.
You can find the maximum permissible
values on the type plates of your vehicle
and the trailer. Always observe the lowest
respective value when determining the
maximum weight with which you can load
the vehicle and the trailer.
R The drawbar noseweight acting on the ball
coupling has to be added to the rear axle
weight in order to prevent the permissible
Gross Axle Weight Rating (GAWR) from
being exceeded. The permissible Gross
Vehicle Weight Rating (GVWR) is specified
on the type plate located on the B-pillar on
the driver's side of your vehicle.
i Mercedes-Benz recommends loading the
trailer so that the drawbar noseweight
remains between 8% and 10% of the
permissible gross trailer weight.
i The weight of additional accessories,
passengers, and cargo reduces the
permissible trailer load and drawbar
noseweight for your vehicle.
Checking the vehicle and trailer weight
R To check that the weights of the towing
vehicle and the trailer comply with the
maximum permissible values, have the
vehicle/trailer combination (including the
driver, passengers, and cargo with a fully
laden trailer) weighed on a calibrated
weighbridge.
R Check the permissible axle weight of the
front and rear axle, the Gross Trailer Weight
(GTW), and the drawbar noseweight.
Check the permissible axle weight of the
front and rear axle, the Gross Trailer Weight
(GTW), and the drawbar noseweight.
Trailer power supply
The trailer power socket of your vehicle is
designed for connecting the 7-pin connector
supplied as part of the Mercedes-Benz-
approved trailer coupling.
i Depending on your trailer, you may need
an adapter to connect your trailer to the
vehicle.
Further information is available from any
authorized Mercedes-Benz Center.
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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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Safety systemsDisplay messagesPossible causes/consequences and M SolutionsESP
Unavailable See
Operator's ManualGRisk of accident
ESP ®
(Electronic Stability Program) and therefore also PRE-
SAFE ®
are temporarily unavailable. The self-diagnosis function
might not be complete, for example. BAS (Brake Assist System)
has also been deactivated.
The brake system continues to function normally, but without the
functions listed above.
XCarefully drive a short distance making slight steering
movements at a speed above 12 mph (20 km/h)
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
XDrive on carefully.XVisit a qualified specialist workshop.ESP ®
and therefore also BAS and PRE-SAFE ®
are not available due
to undervoltage.
The brake system continues to function normally, but without the
functions listed above.XDrive on carefully.XVisit a qualified specialist workshop immediately.If the display message is shown during the journey and the ä
warning lamp is flashing, then 4ETS (Electronic Traction System)
is deactivated. The brakes on the drive wheels could otherwise
overheat.XLet the brakes cool down until the display message disappears
and the ä warning lamp goes out.
4ETS is activated again.ESP
Inoperative See
Operator's ManualGRisk of accident
ESP ®
and therefore also Brake Assist and PRE-SAFE ®
are not
available due to a malfunction. The d warning lamp also lights
up in the instrument cluster.
The brake system continues to function normally, but without the
functions listed above.
XDrive on carefully.XVisit a qualified specialist workshop immediately.214Display messagesOn-board computer and displays
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Display messagesPossible causes/consequences and M SolutionsG
Tele Aid
InoperativeUSA only: one or more main functions in the mbrace system are
malfunctioning.
Canada only: one or more main functions in the Tele Aid system
are malfunctioning.XUSA only: have the mbrace system checked at a qualified
specialist workshop.XCanada only: have the Tele Aid system checked at a qualified
specialist workshop.PRE-SAFE
Inoperative See
Operator's ManualGRisk of injury
Important functions of PRE-SAFE ®
have failed. All other occupant
safety systems, e.g. air bags, remain available.
XVisit a qualified specialist workshop immediately.+
Restraint Sys.
Malfunction
Service RequiredGRisk of injury
The restraint systems are malfunctioning.
XVisit a qualified specialist workshop immediately.GWarning
In the event a malfunction of the SRS is indicated as outlined above, the SRS may not be
operational.
For your safety, we strongly recommend that you contact an authorized Mercedes-Benz Center
immediately to have the system checked. Otherwise the SRS may not be activated when needed
in an accident, which could result in serious or fatal injury, or it might deploy unexpectedly and
unnecessarily which could also result in injury.
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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 SolutionsXVisit a qualified specialist workshop immediately.GWarning
If the 42 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.
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