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EngineProblemPossible causes/consequences and M Solutions;
The yellow engine
malfunction indicator
lamp comes on when
the engine is running.There may be a malfunction in
R the fuel management system
R the ignition system
R the emission control system
R systems which affect emissions
Such malfunctions may result in excessive emissions values and
may switch the engine to limp-home (emergency operation) mode.XHave the vehicle checked as soon as possible at an authorized
Mercedes-Benz Center.
i Some states may by law require you to visit a workshop as
soon as the engine malfunction indicator lamp comes on. Check
local requirements.
;
The yellow engine
malfunction indicator
lamp comes on when
the engine is running.A loss of pressure has been detected in the fuel system. The fuel
cap may not be closed properly or the fuel system may be leaky.XCheck the fuel cap ( Y page 212).XIf it is not closed properly: Close the fuel cap.XIf it is closed properly: Have the fuel system checked by an
authorized Mercedes-Benz Center.?The red coolant
temperature
warning lamp
comes on when
the engine is
running.There is insufficient coolant in the reservoir.
If this warning lamp comes on frequently, there is a leak in the
cooling system.
If the coolant level is correct, the electric radiator fan may be
broken.XImmediately add coolant to prevent engine from overheating
( Y page 216).XHave the cooling system checked.XIf the coolant temperature is below 248‡ (120†), you can
continue driving to the nearest authorized Mercedes-Benz
Center.XAvoid high engine loads (e.g. driving uphill) and stop-and-go
driving.What to do if …295Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 295Z
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ProblemPossible causes/consequences and M Solutions?The red coolant
temperature
warning lamp
comes on when
the engine is
running and an
acoustic
warning sounds.The coolant temperature has exceeded 248‡ (120†).XStop in a safe location as soon as possible and allow the engine
and coolant to cool down.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.
! The engine should not be operated with
the coolant temperature above 248‡
(120†). Doing so may cause serious
damage which is not covered by the
Mercedes-Benz Limited Warranty.
Tires
ProblemPossible causes/consequences and M SolutionshCombination
low tire pressure
telltale/TPMS
malfunction
telltale for the
Advanced TPMS
illuminates
continuously.The Advanced TPMS detects a loss of pressure in at least one tire.XCarefully bring the vehicle to a halt, avoiding abrupt steering and
braking maneuvers. Observe the traffic situation around you.XRead and observe messages in the multifunction display
( Y page 262).
If the tire inflation pressure in the respective tire(s) has (have) been
corrected, the combination low tire pressure/TPMS malfunction
telltale goes out after a few minutes of driving.
hCombination
low tire pressure
telltale/TPMS
malfunction
telltale for the
Advanced TPMS
flashes 60
seconds and
then stays
illuminated.There is a malfunction in the Advanced TPMS.XRead and observe messages in the multifunction display
( Y page 262).XHave the Advanced TPMS checked at an authorized Mercedes-
Benz Center.
After the malfunction has been remedied, the combination low tire
pressure/TPMS malfunction telltale goes out after a few minutes
of driving.
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GWarning!
Each tire, including the spare (if provided),
should be checked at least once a month
when cold and inflated to the inflation
pressure recommended by the vehicle
manufacturer on the Tire and Loading
Information placard on the driver’s door B-
pillar or the tire inflation pressure label on the
inside of the fuel filler flap. If your vehicle has
tires of a different size than the size indicated
on the Tire and Loading Information placard
or the tire inflation pressure label, you should
determine the proper tire inflation pressure
for those tires.
As an added safety feature, your vehicle has
been equipped with a tire pressure monitoring
system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires are significantly underinflated.
Accordingly, when the low tire pressure
telltale illuminates, you should stop and check
your tires as soon as possible, and inflate
them to the proper pressure. Driving on a
significantly underinflated tire causes the tire
to overheat and can lead to tire failure.
Underinflation also reduces fuel efficiency
and tire tread life, and may affect the vehicle’s
handling and stopping ability. Please note that
the TPMS is not a substitute for proper tire
maintenance, and it is the driver’s
responsibility to maintain correct tire
pressure, even if underinflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined with
the low tire pressure telltale. When the
system detects a malfunction, the telltale will
flash for approximately 1 minute and then
remain continuously illuminated. This
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 tires
or 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:
45
The front passenger
front air bag off
indicator lamp
illuminates and
remains illuminated
( Y page 46).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.What to do if …297Practical hintsX204_AKB; 3; 23, en-USd2ureepe,Version: 2.11.8.12009-07-16T19:16:58+02:00 - Seite 297Z
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ProblemPossible causes/consequences and M SolutionsCanada only:
45
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 56).
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:
45
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 262).GWarning!
If the 45 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:
45
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.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 262).298What to do if …Practical hints
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GWarning!
If the 45 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
Runlock 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
XMove locking tab : in the direction of
arrow.
XSlide mechanical key ; out of the housing.Unlocking the driver’s doorXInsert mechanical key ; into the driver’s
door lock.
XTurn mechanical key ; counterclockwise
to position 1.
XPull the door handle 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:
XOpen the driver’s door.XClose the front passenger door, the rear
doors, and the tailgate.
XPress the central locking switch
(Y page 71).
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.
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XRemove mechanical key ; from the
SmartKey (Y page 299).
XInsert mechanical key ; into the driver’s
door lock.
XTurn mechanical key ; clockwise to
position 1.
The vehicle is locked.
XTurn mechanical key ; back and remove
it from the driver’s door lock.
XCheck whether the doors and the tailgate
are locked.
iThis procedure does not arm the anti-
theft alarm system, nor does it lock the fuel
filler flap.
Unlocking and opening the tailgate
If the tailgate can no longer be unlocked and
opened using button F on the SmartKey
or the KEYLESS-GO function, use the
emergency release to unlock and open the
tailgate.
The emergency release is located on the
inside of the tailgate.
A minimum height clearance of 6.9 ft
(2.10 m) is required to open the tailgate.
XRemove the mechanical key from the
SmartKey (Y page 299).
XInsert mechanical key ; into the opening
in trim :.
XPress mechanical key ; in direction of the
arrow and open the tailgate.
! The tailgate swings up and beyond the
rear bumper when opening. Therefore,
make sure there is sufficient clearance
above and behind the vehicle.
XOpen the tailgate.
iIf the vehicle has previously been locked
from the outside using the SmartKey or
KEYLESS-GO, opening the tailgate from the
inside using the emergency release will
trigger the anti-theft alarm system.
To cancel the alarm, do one of the
following:RInsert the SmartKey into the starter
switch.
RPress button % or & on the
SmartKey.
In vehicles with KEYLESS-GO:RPull an outside door handle.
The SmartKey must be within 3 ft (1 m)
of the vehicle.
RPress the KEYLESS-GO start/stop
button.
The SmartKey must be inside the vehicle.
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Manually unlocking the gear selector
lever
If the vehicle’s electrical system is
malfunctioning, the gear selector lever could
remain locked in park position P. In this case
the gear selector lever can be unlocked
manually, e.g. to tow the vehicle.
XEngage the parking brake.
! Do not use sharp objects to loosen the
gear selector lever cover in the center
console, as this could damage the gear
selector lever cover or the center console.
XInsert a flat, blunt object into the right edge
of gear selector lever cover : at the
positions indicated by the arrows.
XLoosen gear selector lever cover : using
this object.
XPull gear selector lever cover : out and
remove.
XSimultaneously push down release ; and
move the gear selector lever out of park
position P.
The gear selector lever is unlocked.
iThe gear selector lever is locked again as
soon as you move it back to park position
P.
Fuel filler flapGWarning!
Avoid contact with the vehicle walls as they
may contain sharp edges. Otherwise, you
could injure yourself while releasing the fuel
filler flap.
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 71).XOpen the passenger-side trim panel
(Y page 309).
XPull fuel filler flap release :.
The fuel filler flap is unlocked.
XOpen the fuel filler flap (Y page 212).XClose the passenger-side trim panel.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.
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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.
XPush the head restraint cushion at the
bottom, back as far as possible ;.
XPush the head restraint cushion down into
the guide =.
XFold the head restraint cushion by the top,
back firmly until it engages :.
XRepeat this procedure on the NECK-PRO
active front head restraint for the second
front seat.
For information on NECK-PRO active front
head restraints, see “NECK-PRO active front
head restraints” (Y page 51).
Replacing SmartKey batteries
If the batteries in the SmartKey are
discharged, the vehicle can no longer be
locked or unlocked. It is recommended to
have the batteries replaced at an authorized
Mercedes-Benz Center.
GWarning!
Batteries contain poisonous and corrosive
substances. Therefore, keep the batteries out
of reach of children.
If a battery is swallowed, seek medical help
immediately.
GWarning!
SmartKey batteries contain perchlorate
material, which may require special handling
and regard for the environment. Check with
your local government’s disposal guidelines.
California residents, see www.dtsc.ca.gov/
HazardousWaste/Perchlorate/
index.cfm.
Batteries contain materials that can harm the
environment if disposed of improperly.
Recycling of batteries is the preferred method
of disposal. Many states (USA only) or
provinces (Canada only) require sellers of
batteries to accept old batteries for recycling.
When inserting the batteries, make sure they
are clean and free of lint.
When replacing batteries, always replace
both batteries.
iThe required replacement batteries are
available at any authorized Mercedes-Benz
Center.
Replacement batteries: Lithium, type
CR 2025 or equivalent.
XRemove the mechanical key from the
SmartKey (Y page 299).
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