recognize dangers in time, cause an accident
and injure yourself and others.
Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the turn
signal, a double warning tone sounds. Red
warning lamp : flashes. If the turn signal
remains on, detected vehicles are indicated
by the flashing of red warning lamp :. There
are no further warning tones.
Switching on Blind Spot Assist
XMake sure that the radar sensor system
( Y page 208) and Blind Spot Assist
( Y page 210) are activated in the on-board
computer.XTurn the key to position 2 in the ignition
lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical
connection. This can be accomplished by
checking the trailer lighting. In this event,
Blind Spot Assist is deactivated. The indicator
lamp lights up yellow in the exterior mirrors
and the message: Blind Spot Assist
Currently Unavailable See
Operator's Manual appears in the
multifunction display.
i The indicator lamps in the exterior mirrors
can be switched off.
To do this, you must deactivate Blind Spot
Assist when:
R the key is in position 2 in the ignition
lock.
R the engine is not running.
R the electrical connection to the trailer
has been established.
Towing a trailer
Notes on towing a trailer
Important safety instructions
GWarning!
Failure to use proper equipment and driving
technique can result in a loss of vehicle
control when towing a trailer.
Improper towing or failure to follow the
instructions in this manual can result in
vehicle damage and/or serious personal
injury. Follow the guidelines below carefully
to assure safe trailer operation.
Contact an authorized Mercedes-Benz Center
should you require an explanation of
information contained in this manual.
General information
R Only install an approved trailer coupling on
your vehicle.
Further information on availability and on
installation is available from any authorized
Mercedes-Benz Center.
R The bumpers of your vehicle are not
suitable for installing detachable trailer
couplings.
R Do not install hired trailer couplings or
other detachable trailer couplings on the
bumpers of your vehicle.
R To reduce the risk of damage to the ball
coupling, remove it from the ball coupling
recess when not in use.
Coupling up 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.
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Make sure that you do not operate the ADS
switch or the vehicle level control system
when coupling/decoupling the trailer.
Observe the maximum permissible trailer
dimensions (width and length).
Most federal states and all Canadian
provinces require by law:
R safety chains between the towing vehicle
and the trailer. The chains should be cross-
wound under the trailer drawbar. They must
be fastened to the vehicle's trailer
coupling, not to the bumper or the axle.
Allow for enough play in the chains to
facilitate turning tight corners.
R a separate brake system for certain types
of trailer.
R a safety switch for braked trailers. Check
the specific legal requirements applicable
to your federal state.
If the trailer detaches from the towing
vehicle, the safety switch applies the
trailer's brakes.
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is
equipped with an anti-lock brake system.
Doing so will result in a loss of function of
the brake systems of both the vehicle and
the trailer.
i The vehicle's wiring harness features a
line to the brake indicator lamp.XMake sure that the automatic transmission
is set to position P.XApply the vehicle's parking brake.XStart the engine.XVehicles with the AIRMATIC package:
select highway level and set ADS to
AUTO or COMF .XSwitch off the engine.XClose all doors and the tailgate.XCouple up the trailer.XEstablish all electrical connections.i
Vehicles with the AIRMATIC package:
with a trailer attached, the vehicle will
always remain at highway level. When
coupling up a trailer, please observe the
following:
R if highway level has not been set
manually, the vehicle will automatically
sink to highway level as soon as it
reaches a speed of 5 mph (8 km/h).
R high-speed level is not available.
These restrictions apply to all accessories
powered through a connection to the trailer
power socket of your vehicle, e.g. a bicycle
carrier.
Towing a trailer
There are numerous legal requirements
concerning the towing of a trailer, e.g. speed
restrictions. Make sure that your vehicle/
trailer combination complies with the local
requirements not only in your area of
residence but also at any location to which
you are traveling. The police and local
authorities can provide reliable information.
Please observe the following when towing a
trailer:
R To acquaint yourself with driving with a
trailer and with the resulting changes to
handling, you should practice cornering,
stopping and reversing in a traffic-free
location.
R Before driving, check:
- the trailer coupling
- the safety switch for braked trailers
- the safety chains
- the electrical connections
- the lights
- the wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer features electronically
controlled brakes, pull away the vehicle/
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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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GWarning
Driving with the brake warning lamp illuminated can result in an accident. Have your brake system
checked immediately if the brake warning lamp stays on. Do not add brake fluid before checking
the brake system.
Overfilling the brake fluid reservoir can result in spilling brake fluid on hot engine parts and the
brake fluid catching fire. You can be seriously burned.
Seat belt
ProblemPossible causes/consequences and M Solutions7
After starting the
engine, the red seat
belt warning lamp lights
up for 6 seconds.The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.XFasten your seat belt ( Y page 54).7
After starting the
engine, the red seat
belt warning lamp lights
up. In addition, a
warning tone sounds
for up to 6 seconds.GRisk of injury
The driver's seat belt is not fastened.
XFasten your seat belt ( Y page 54).
The warning tone ceases.7
The red seat belt
warning lamp lights up
after the engine starts,
as soon as the driver's
or the front-passenger
door is closed.GRisk of injury
The driver or front passenger has not fastened their seat belt.
XFasten your seat belt ( Y page 54).
The warning lamp goes out.GRisk of injury
There are objects on the front-passenger seat.
XRemove the objects from the front-passenger seat and stow
them in a secure place.
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ProblemPossible causes/consequences and M Solutions7
The red seat belt
warning lamp flashes
and an intermittent
audible warning
sounds.GRisk of injury
The driver or front passenger has not fastened their seat belt. In
addition, you are driving faster than 15 mph (25 km/h) or you have
briefly driven faster than 15 mph (25 km/h).
XFasten your seat belt ( Y page 54).
The warning lamp goes out and the intermittent audible warning
ceases.GRisk of injury
There are objects on the front-passenger seat. In addition, you are
driving faster than 15 mph (25 km/h) or you have briefly driven
faster than 15 mph (25 km/h).
XRemove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out and the intermittent audible warning
ceases.238Warning and indicator lamps in the instrument clusterOn-board computer and displays
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Vehicle equipment ............................246
Loading guidelines ............................246
Stowage compartments ...................246
Stowage areas .................................. 249
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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.
Loading guidelines
GWarning!
Always fasten items being carried as securely
as possible. Use cargo tie-down rings and
fastening materials appropriate for the weight
and size of the load.
In an accident, during hard braking or sudden
maneuvers, loose items will be thrown around
inside the vehicle. This can cause injury to
vehicle occupants unless the items are
securely fastened in the vehicle.
To help avoid personal injury during a collision
or sudden maneuver, exercise care when
transporting cargo. Do not pile luggage or
cargo higher than the seat backrests.
The cargo compartment is the preferred place
to carry objects. Always use cargo tie-down
rings, and if so equipped, always use the cargo
net when transporting cargo.
Never drive a vehicle with the tailgate open.
Deadly carbon monoxide (CO) gases may
enter vehicle interior resulting in
unconsciousness and death.
The gross vehicle weight (GVW) is the weight
of the vehicle including fuel, the vehicle tool
kit, spare tire, any installed accessories,
vehicle occupants and luggage/cargo.
The load limit and the gross vehicle weight
rating (GVWR) of your vehicle must never be
exceeded. The load limit and the GVWR are
stated on the vehicle identification plate on
the B-pillar on the driver's side
( Y page 330).
Additionally, the cargo must be distributed so
that the weight on each axle never exceeds
the maximum gross axle weight rating
(GAWR) for the front and rear axles. The data
on GVWR and GAWR is stated on the vehicle
identification plate on the B-pillar on the
driver's side ( Y page 330).
Further information can be found in the
"Loading the vehicle" section ( Y page 330).
The handling characteristics of a laden
vehicle are dependent on the distribution of
the load within the vehicle. For this reason,
you should observe the following notes when
transporting a load:
R Position heavy loads as far forwards as
possible and as low down in the cargo
compartment as possible.
R The load must not protrude above the
upper edge of the seat backrests.
R always place the load against the rear or
front seat backrests. Make sure that the
seat backrests are securely locked into
place.
R Hook in the cargo net when loading.
R Always place the load behind unoccupied
seats if possible.
R Secure the load with sufficiently strong and
wear-resistant tie down. Pad sharp edges
for protection.
Stowage compartments
Important safety guidelines
GWarning!
To help avoid personal injury during a collision
or sudden maneuver, exercise care when
storing objects in the vehicle. Put luggage or
cargo in the cargo compartment if possible.
Do not pile luggage or cargo higher than the
seat backrests.
246Stowage compartmentsLoading, stowing and features
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