
sequence will continue upon subsequent
vehicle start-ups as long as the malfunction
exists. When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of
incompatible replacement or alternate tiresor wheels on the vehicle that prevent the
TPMS from functioning properly. Always
check the TPMS malfunction telltale after
replacing one or more tires or wheels on your
vehicle to ensure that the replacement or
alternate tires and wheels allow the TPMS to
continue to function properly.
Lamp in center console
ProblemPossible causes/consequences and  M SolutionsCanada only:
42
The front passenger
front air bag off
indicator lamp
illuminates and
remains illuminated
( Y  page 47).A BabySmart TM
 child seat is installed on the front passenger seat.
Therefore the front passenger front air bag is switched off.The system is malfunctioning when there is no BabySmart TM
 child
seat installed on the front passenger seat.XHave the system checked as soon as possible at an authorized
Mercedes-Benz Center.Canada only:
42
The front passenger
front air bag off
indicator lamp does not
illuminate or does not
remain illuminated with
a BabySmart TM
 child
seat properly installed
on the passenger seat.The system is malfunctioning.XMake sure there is nothing between seat cushion and child seat.XCheck installation of the child seat ( Y page 58).
If the front passenger front air bag off indicator lamp remains out:
XHave the system checked as soon as possible at an authorized
Mercedes-Benz Center.
Do not use the BabySmart TM
 restraint to transport children on the
front passenger seat until the system has been repaired.
USA only:
42
The front passenger
front air bag off
indicator lamp
illuminates and
remains illuminated
with the weight of a
typical adult or
someone larger than a
small individual on the
front passenger seat.The system is malfunctioning.XHave the system checked as soon as possible at an authorized
Mercedes-Benz Center.XRead and observe messages in the multifunction display and
follow corrective steps ( Y page 287).322What to do if …Practical hints
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GWarning!
If the 42 indicator lamp
illuminates and remains illuminated with the
weight of a typical adult or someone larger
than a small individual on the front passenger
seat, do not have any passenger use the front
passenger seat until the system has been
repaired.
ProblemPossible causes/consequences and M SolutionsUSA only:
42
The front passenger
front air bag off
indicator lamp does not
illuminate and/or does
not remain illuminated
with the weight of a
typical 12-month-old
child in a standard child
restraint or less on the
front passenger seat.
The system is malfunctioning.XMake sure there is nothing between seat cushion and child seat
and check installation of the child seat.
XMake sure no objects applying supplemental weight onto the
seat are present.
XMake sure no objects which apply forces to the seat are present
(e.g. objects such as books, briefcases etc. lodged behind or
around the seat, head restraints pushing against roof etc.). The
system may recognize such forces as supplemental weight.
XIf the front passenger front air bag off indicator lamp remains
out, have the system checked as soon as possible at an
authorized Mercedes-Benz Center. Do not transport a child on
the front passenger seat until the system has been repaired.
XRead and observe messages in the multifunction display and
follow corrective steps (Y page 287).
GWarning!
If the 42 indicator lamp does not
illuminate or remains out with the weight of a
typical 12-month-old child in a standard child
restraint or less on the front passenger seat,
do not transport a child on the front
passenger seat until the system has been
repaired.
Unlocking/locking manually
Unlocking the vehicle
If you cannot unlock the vehicle with the
SmartKey or with KEYLESS-GO, unlock the
driver’s door using the mechanical key.
The anti-theft alarm system will trigger when
you
Runlocking the driver’s door with the
mechanical key
and
Ropen the driver’s door
To cancel the alarm, insert the SmartKey into
the starter switch.
Removing the mechanical key 
SmartKey
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SmartKey with KEYLESS-GO
XMove locking tab : in the direction of
arrow.
XSlide mechanical key ; out of the housing.
Unlocking the driver’s door
XInsert mechanical key ; into the driver’s
door lock.
XTurn mechanical key ; counterclockwise
to position 1.
XPull the door handle past the resistance
point until the locking knob moves up.
The driver’s door is unlocked.
XPull the door handle once more to open the
driver’s door.
XTurn mechanical key ; back and remove
it from the driver’s door lock.Locking the vehicle
If you cannot lock the vehicle with the
SmartKey or with KEYLESS-GO, lock it as
follows:
XClose the front passenger door, the right
rear door, and the tailgate.
XOpen the driver’s door and the rear left
door.
XPress the central locking switch
(Y page 75).
The locking knobs of the front passenger
door and the rear doors move down.
XIf the vehicle battery is disconnected or 
drained: Press down the locking knobs on
the front passenger door and the rear
doors.
XExit the vehicle.XClose the driver’s door.XEnter the vehicle through the rear left door.XPress down the locking knob of the driver’s
door.
! To prevent inadvertent lockout, make
sure to have the SmartKey with you before
proceeding with the next step. The next
step will lock the vehicle.
XExit the vehicle.XClose the rear left door.
The vehicle is locked.
iThis procedure does not arm the anti-
theft alarm system, nor does it lock the fuel
filler flap.
Fuel filler flap
GWarning!
Avoid contact with the vehicle walls as they
may contain sharp edges. Otherwise, you
could injure yourself while releasing the fuel
filler flap.
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In case the central locking system does not
release the fuel filler flap, you can open it
manually.
The fuel filler flap release is located on the
passenger side in the cargo compartment
behind the cover.
XOpen the tailgate (Y page 75).XOpen the cover on the passenger-side trim
panel (Y page 332).
XPull red fuel filler flap release : in
direction of arrow.
The fuel filler flap is unlocked.
XOpen the fuel filler flap (Y page 226).XClose the cover.XClose the tailgate.
Resetting activated NECK-PRO active 
front head restraints
If the NECK-PRO active front head restraints
have been triggered in a rear-end collision,
they must be reset.
You can tell that the NECK-PRO active front
head restraints have been triggered when
they have been moved forward and cannot be
adjusted.
GWarning!
For safety reasons, have the NECK-PRO active
front head restraints checked at an
authorized Mercedes-Benz Center after a
rear-end collision.
GWarning!
When pushing back the head restraint
cushion, make sure your fingers do not
become caught between the head restraint
cushion and the cover. Failing to do so may
lead to injury.
iPressing the head restraint cushion back
requires high force. If you encounter
difficulties when pushing the head restraint
back, please have the procedure
performed at an authorized Mercedes-Benz
Center.
Head restraints (standard)
XPull the top of the head restraint cushion in
direction of arrow : as far as it will go.
XAdjust the head restraint cushion
downward in direction of arrow ; as far as
it will go.
XFirmly press the top of the head restraint
cushion towards the head restraint cover in
direction of arrow = until it engages.
XRepeat this procedure on the NECK-PRO
active front head restraint for the second
front seat.
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Correct headlamp adjustment is extremely
important. High beam adjustments
simultaneously aim the low beam. To check
and readjust a headlamp, follow the steps
described:
XPark the vehicle on a level surface 25 feet
(7.6 m) from a vertical test screen or wall.
XMake sure the vehicle has a normal tailgate
load.
XSwitch on the low beam headlamps L.
If the beam does not show a beam pattern as
indicated in the figure left, then follow the
steps below:
XOpen the hood (Y page 228).
The adjustment screws are located under the
cover panel.
XInsert a suitable tool into the openings in
the panel cover. The direction of arrows
= and ? indicate the angle in which the
tool has to be inserted in oder to access the
adjustment screws.
XAlways turn the adjustment screws equally
for vertical adjustment until the headlamp
is adjusted as shown in :. Turn clockwise
for upward movement and
counterclockwise for downward
movement.
Graduations:
RScrew at arrow =: 0.67° pitch
RScrew at arrow ?: 0.50° pitch
The left and right headlamps must be
adjusted individually.
iIf it is not possible to obtain a proper
headlamp adjustment, have the system
checked at an authorized Mercedes-Benz
Center.
Replacing wiper blades
Safety notes
GWarning!
For safety reasons, switch off the wipers and
remove the SmartKey from the starter switch
(vehicles with KEYLESS-GO: Make sure the
vehicle’s on-board electronics have status 0)
before replacing a wiper blade. Otherwise, the
wiper motor could suddenly turn on and cause
injury.
GWarning!
Wiper blades are components that are subject
to wear and tear. Replace the wiper blades
twice a year, preferably in the spring and fall.
Otherwise the windows will not be wiped
properly. As a result, you may not be able to
observe surrounding traffic conditions and
could cause an accident.
! Never open the hood when a front wiper
arm is folded forward.
Hold on to the wiper when folding a wiper
arm back. If released, the force of the
impact from the tensioning spring could
crack the windshield or the rear window.
Do not allow a wiper arm to contact the
windshield glass or the rear window
without a wiper blade inserted.
Mercedes-Benz recommends that you have
this work carried out at an authorized
Mercedes-Benz Center.
XRemove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO:
XMake sure the vehicle’s on-board
electronics have status 0 (Y page 80).
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Rear wiper bladeXInsert wiper blade ; into wiper arm :.XHold wiper arm : and engage wiper
blade ; by pushing it in direction of arrow
until it locks into place.
XCheck whether the wiper blade is securely
fastened.
XFold wiper arm : to rest on the rear
window.
Make sure to hold on to the wiper when
folding the wiper arm back.
! Make sure the wiper blade is installed
properly. An improperly installed wiper
blade may cause rear window damage.
Flat tire
Safety notes
Your vehicle may be equipped with an
MOExtended system or a Minispare wheel.
Vehicles with an MOExtended system do not
have a spare wheel or a TIREFIT kit.
For information on your vehicle’s equipment,
see “Rims and tires” (Y page 365).
GWarning!
The dimensions of the spare wheel are
different from those of the road wheels. As a
result, the vehicle handling characteristics
change when driving with a spare wheel
mounted. Adapt your driving style
accordingly.
The spare wheel is for temporary use only.
When driving with a spare wheel mounted,
ensure proper tire inflation pressure and do
not exceed a vehicle speed of 50 mph
(80 km/h).
Contact the nearest authorized Mercedes-
Benz Center as soon as possible to have the
spare wheel replaced with a regular road
wheel.
Never operate the vehicle with more than one
spare wheel mounted.
Do not switch off the ESP® when a spare
wheel is mounted.
GWarning!
Your vehicle is equipped with air suspension
program. Do not open or close any doors or
the tailgate while mounting a spare wheel. The
vehicle could rise or lower to a previously
selected level. You or others could be injured
as a result.
Preparing the vehicle
XMake sure the vehicle level is set to
highway level (Y page 159).
XWhenever possible, park the vehicle in a
safe distance from moving traffic on a hard,
flat surface.
XTurn on the hazard warning flasher.XTurn the steering wheel so that the front
wheels are in a straight-ahead position.
XEngage the parking brake.XShift the automatic transmission into park
position P.
XTurn off the engine.XRemove the SmartKey from the starter
switch.
or
XVehicles with KEYLESS-GO: Open the
driver’s door (this puts the starter switch in
position 0, same as with the SmartKey
removed from the starter switch). The
driver’s door can then be closed again.
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GWarning!
Have the tightening torque checked after
changing a wheel. The wheels could come
loose if they are not tightened to a torque of
110 lb-ft (150 Nm).
XFully collapse the jack to storage position,
see ( Y page 286).XStore the jack and the other vehicle tools
in the designated storage space.
For information on storing the spare wheel
after it has been replaced by a regular road
wheel, see ( Y page 286).
i The damaged road wheel cannot be
stored in the spare wheel well under the
cargo compartment floor. It should be
transported in the cargo compartment
wrapped in a protective wrap.
i USA only:
Do not restart the tire inflation pressure
monitor until a full size wheel/tire with
functioning sensor has been placed back
into service on the vehicle.
MOExtended system
The MOExtended system allows you to
continue driving your vehicle even if there is
a total loss of pressure in one or more tires.
You may only use the MOExtended system in
conjunction with the tire pressure loss
warning system ( Y page 237) or the
Advanced TPMS ( Y page 239).
The maximum distance in emergency mode
depends on the vehicle’s load. It is 50 miles
(80 km) if the vehicle is partially loaded and
18 miles (30 km) if the vehicle is fully loaded.
The point at which the maximum driving
distance in emergency mode begins is when
the warning message appears in the
multifunction display indicating that there is
a loss of tire inflation pressure.
XDo not exceed the maximum speed of
50 mph (80 km/h).GWarning!
In emergency mode, your vehicle’s driving
characteristics are diminished in such
situations as:
R driving around curves
R while braking
R while accelerating rapidly
Therefore, your driving style must be adapted
accordingly. Avoid abrupt steering and driving
maneuvers, as well as driving over obstacles
(road curbs, potholes, or off-road areas). This
is especially important if the vehicle is heavily
loaded.
The emergency driving distance that can be
achieved greatly depends on the demands
placed on the vehicle. Depending on speed,
load, driving maneuvers, road conditions,
outside temperature, etc., the distance can be
significantly shorter or, if the vehicle is driven
cautiously, somewhat longer.
Do not continue driving in emergency mode if
R you notice knocking sounds
R the vehicle starts to shake
R smoke develops and you smell rubber
R ESP ®
 is intervening continuously
R you notice tears on the tire sidewalls
After driving in emergency mode, you must
have the rims inspected by an authorized
Mercedes-Benz Center to check if they are
suitable for further use. The failed tire must
be replaced in any case.
When replacing individual or all tires on the
vehicle, make sure only tires marked with
“MOExtended” are mounted in the size
specified for your vehicle ( Y page 365).
Bleeding the fuel system (diesel 
engine only)
Driving the vehicle until the fuel tank is empty
is not recommended. Otherwise, air may be
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sucked into the fuel system. If this happens,
the malfunction indicator lamp  = (USA
only) or  ; (Canada only) comes on and the
engine may not start immediately after
refueling the vehicle.
After refueling:XMake sure the automatic transmission is in
park position  P.
The transmission position indicator in the
multifunction display should be on  P.XDo not depress the accelerator.XIf necessary, remove the KEYLESS-GO
start/stop button from the starter switch.XTurn the SmartKey in the starter switch to
position  2 for at least 10 seconds.XReturn the SmartKey in the starter switch
to position  0.XTurn the SmartKey in the starter switch to
position  3 and hold it there for a maximum
of 10 seconds or until the engine runs
surge-free.
If the engine does not start:
XTurn the SmartKey in the starter switch
once more to position  2 for at least
10 seconds.XReturn the SmartKey in the starter switch
to position  0.XTurn the SmartKey in the starter switch
once more to position  3 and hold it there
for a maximum of 10 seconds or until the
engine runs surge-free.XIf necessary, repeat the above steps.
If the engine still does not start after
3 attempts:
Do not make any further attempts to start the
engine. Contact an authorized Mercedes-
Benz Center or call Roadside Assistance
( Y  page 216).
i When the malfunction indicator lamp
=  (USA only) or  ; (Canada only) in
the instrument cluster has been illuminated
for the above condition, it will remain
illuminated until the engine was cycled on
and off four times in a row.
AdBlue ®
 (diesel engine only)
The BlueTEC exhaust gas aftertreatment
system requires a reducing agent (AdBlue ®
)
in order to function properly. Refilling with
AdBlue ®
 is part of the regular maintenance
service work. A tankful of AdBlue ®
 should
suffice until the next maintenance service
under normal driving conditions.
When the AdBlue ®
 tank is low, the message
Check Additive See Operator’s 
Manual  appears in the multifunction display.
When the AdBlue ®
 level drops to the
minimum level, the message  Remaining 
Starts: 20  appears in the multifunction
display.
i When the message  Remaining Starts: 
20  appears in the multifunction display, you
can start the engine 20 more times. If you
do not add AdBlue ®
, the engine cannot be
started beyond that point. Fill the
AdBlue ®
 tank with approximately 1 gal
(3.79 l) AdBlue ®
 (corresponds to
approximately 2 AdBlue ®
 refill containers)
or have the AdBlue ®
 tank filled by an
authorized Mercedes-Benz Center.
i For refilling outside the maintenance
service intervals, refill the AdBlue ®
 tank
with approximately 1 gal (3.79 l) AdBlue ®
(corresponds to approximately 2 AdBlue ®
refill containers).
Always use the particular AdBlue ®
 refill
containers for refilling outside the
maintenance service interval. Contact an
authorized Mercedes-Benz Center or call
Roadside Assistance if necessary
( Y  page 216).
Additional information on BlueTEC exhaust
gas aftertreatment and AdBlue ®
 is available
at any authorized Mercedes-Benz Center.346AdBlue ®
 (diesel engine only)Practical hints
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