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G
Warning!
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.
Problem
Possible causes/consequences and
X 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.
X
Make sure there is nothing between seat cushion and child seat
and check installation of the child seat.
X Make sure no objects applying supplemental weight onto the
seat are present.
X Make 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.
X If 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.
X Read and observe messages in the multifunction display and
follow corrective steps (Y page 274). G
Warning!
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
R unlocking the driver’s door with the
mechanical key and
R open the driver’s door
To cancel the alarm, insert the SmartKey into
the starter switch.
Removing the mechanical key SmartKey308
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SmartKey with KEYLESS-GO
X
Move locking tab : in the direction of
arrow.
X Slide mechanical key ; out of the housing.
Unlocking the driver’s door X
Insert mechanical key ; into the driver’s
door lock.
X Turn mechanical key ; counterclockwise
to position 1.
X Pull the door handle past the resistance
point until the locking knob moves up.
The driver’s door is unlocked.
X Pull the door handle once more to open the
driver’s door.
X Turn 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:
X Close the front passenger door, the right
rear door, and the tailgate.
X Open the driver’s door and the rear left
door.
X Press the central locking switch
(Y page 74).
The locking knobs of the front passenger
door and the rear doors move down.
X If the vehicle battery is disconnected or
drained: Press down the locking knobs on
the front passenger door and the rear
doors.
X Exit the vehicle.
X Close the driver’s door.
X Enter the vehicle through the rear left door.
X Press 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.
X Exit the vehicle.
X Close the rear left door.
The vehicle is locked.
i This procedure does not arm the anti-
theft alarm system, nor does it lock the fuel
filler flap. Fuel filler flap
G
Warning!
Avoid contact with the vehicle walls as they
may contain sharp edges. Otherwise, you
could injure yourself while releasing the fuel
filler flap. Unlocking/locking manually
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battery cover is non-removable. Do not
attempt to open the battery as otherwise
the battery will be damaged.
VRLA
batteries do not require topping-up of
the electrolyte level. They cannot be
opened to check the electrolyte level.
However, the battery condition must be
checked periodically by performing a
battery conductance test. Refer to
Maintenance Booklet for battery condition
testing intervals.
The factory-equipped battery may only be
replaced with a battery that
R has the same security features
R is of identical size
R is of identical voltage
R is of identical capacity
! As any other battery, the battery may
discharge if you do not operate the vehicle
for an extended period of time. Have the
battery disconnected at a qualified
workshop or an authorized Mercedes-Benz
Center in such a case. You may also
connect an accessory battery charge unit
expressly approved by Mercedes-Benz for
your vehicle model to maintain the battery
charge. Contact an authorized Mercedes-
Benz Center for further information.
The battery, the battery ventilation hose
and the lateral plug must always be
securely installed when the vehicle is in
operation.
! Never loosen or detach battery terminal
clamps while the engine is running or the
SmartKey is in the starter switch or
KEYLESS-GO button is in position 1.
Otherwise the alternator and other
electronic components could be severely
damaged.
Have the battery checked regularly at an
authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for
maintenance intervals or contact an authorized Mercedes-Benz Center for
further information.
i After battery power was interrupted, do
the following:
R Set the clock
(Y page 133).
Vehicles with COMAND system with
navigation module: Time and date are set
automatically.
R Synchronize the door windows
(Y page 107).
R Synchronize the power tilt/sliding
sunroof (Y page 183).
R Synchronize the power tilt/sliding panel
(Y page 186).
R Synchronize the exterior rear view
mirrors (Y page 96). Charging the battery
G
Warning!
Never charge a battery while still installed in
the vehicle unless the accessory battery
charge unit approved by Mercedes-Benz is
being used. Gases may escape during
charging and could cause an explosion that
may
result in personal injury, paint damage or
corrosion.
An accessory battery charge unit specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available. It permits the charging of the
battery in its installed position. Contact an
authorized Mercedes-Benz Center for
information and availability.
Charge battery in accordance with the
separate instructions for the accessory
battery charger.
Have the battery charged at an authorized
Mercedes-Benz Center. If you charge the
battery yourself, follow the operating
instructions for your charging device. Battery
335
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