335 Practical hints
What to do if …
Display symbol
Display messages
Possible cause
Possible solution
A
Reserve fuel
The fuel level has dropped below the re-
serve mark.
Refuel at the next gas station
(page 278).
Y
Hood open!
You are driving with the hood open.
Close the hood (
page 281).
F
Key
Check battery!
The SmartKey with KEYLESS-GO* batter-
ies are discharged.
Change the batteries (
page 355).
Key
not recognized!
The SmartKey with KEYLESS-GO* is not
recognized while the engine is running
because
the SmartKey with KEYLESS-GO* is
not in the vehicle
there is strong radio-frequency inter-
ference
Stop the vehicle as soon as it is safe
to do so.
Search for the SmartKey.
Otherwise the vehicle cannot be cen-
trally locked nor can the engine be
started again after the engine is
stopped.
The SmartKey with KEYLESS-GO* is mo-
mentarily not recognized.
Change the position of the SmartKey
in the vehicle.
Operate the vehicle with the Smart-
Key in the starter switch if necessary.
353 Practical hints
Unlocking / locking in an emergency
Unlocking / locking in an emergency
Unlocking the vehicle
If you are unable to unlock the vehicle with
the SmartKey, open the driver’s door and
the trunk using the mechanical key.
1Mechanical key locking tab
2Mechanical key
Move locking tab1 in the direction of
the arrow and slide mechanical key2
out of the housing.Unlocking the driver’s door
3Unlocking
4Locking
Unlock the door with the mechanical
key. To do so, push the mechanical key
in the lock until it stops and turn it to
the left.
iUnlocking your vehicle with the me-
chanical key will trigger the anti-theft
alarm system. To cancel the alarm, do
one of the following:
Press button Œ or ‹ on the
SmartKey.
Insert the SmartKey in the starter
switch.
Press the KEYLESS-GO* start/stop
button (
page 33).
354 Practical hintsUnlocking / locking in an emergencyUnlocking the trunk
A minimum height clearance of 5.90 ft
(1.80 m) is required to open the trunk lid.
If you are unable to unlock the trunk with
the SmartKey or KEYLESS-GO*, open the
trunk with the mechanical key.
The handle is located above the rear li-
cense plate recess.
1Unlocking in an emergency
2Handle
Insert the mechanical key into the
trunk lid lock.
Turn the mechanical key counterclock-
wise to position1 and hold it in this
position.
Pull trunk lid handle2 and lift the
trunk lid.
Locking the vehicle
If you are unable to lock the vehicle with
the SmartKey, lock it with the mechanical
key as follows:
Close the passenger doors and the
trunk.
Press the central locking switch in the
cockpit (
page 107).
Check to see whether the locking
knobs on the passenger doors are still
visible. If necessary, push them down
manually.
Slide mechanical key2 out of the
SmartKey.
Lock the driver’s door with the me-
chanical key (
page 354).
Check if the trunk is locked. If neces-
sary lock the trunk with the mechanical
key (if appilcable) (
page 105).
!Always make sure there is sufficient
overhead clearance.iUnlocking your vehicle with the me-
chanical key will trigger the anti-theft
alarm system. To cancel the alarm, do
one of the following:
Press buttonŒ or‹ on the
SmartKey.
Insert the SmartKey in the starter
switch.
Vehicles with KEYLESS-GO*:
Grasp the outside door handle.
Press the start /stop button.
368 Practical hintsFlat tire
Unscrew the valve cap from tire
valve7.
Screw filler hosea onto tire valve7.
Insert electrical plug4 into vehicle
cigarette lighter socket.
Turn SmartKey in starter switch to
position1 (
page 31).
or
Press the KEYLESS-GO* start / stop
button (
page 33) on the selector le-
ver once. Do not depress brake pedal.
Press I on electric air pump switch8.
The electric air pump should now
switch on and inflate the tire.After five minutes, the pressure gauge
must display at least 26 psi (1.8 bar). The
air hose can become hot during inflation.
Please exercise appropriate caution.
If this tire pressure is not attained, turn
off the electric air pump, detach the fill-
er hose from the tire valve, and drive
vehicle back and forth very slowly ap-
proximately 30 ft (10 m).
This serves to better distribute the
TIREFIT sealant material inside the tire.
Unscrew the air pump’s air hose5
from flange6 of the TIREFIT contain-
er.
Screw air hose5 onto tire valve7.
Inflate the tire again.
After attaining a tire pressure of 26 psi
(1.8 bar), press 0 on electric air pump
switch8.
The electric air pump should now be
switched off.
iIf sealant has leaked out, let it dry. You
can then peel it off.
!Do not operate the electric air pump
longer than eight minutes without in-
terruption. Otherwise it may overheat.
You may operate the air pump again af-
ter it has cooled off.
Warning!
G
If a tire pressure of 26 psi (1.8 bar) is not at-
tained, tire is too severely damaged for
TIREFIT to provide a reliable tire repair.
In this case, TIREFIT cannot properly seal
the tire.
Do not drive the vehicle.
Contact the nearest Mercedes-Benz Center
or call Roadside Assistance.
369 Practical hints
Flat tire
Turn SmartKey in starter switch to
position0 (
page 31).
or
Press the KEYLESS-GO* start / stop
button (
page 33) on the selector le-
ver twice. Do not depress brake pedal.
Detach the electric air pump.
The air hose may still be hot. Please ex-
ercise appropriate caution.
Store the electrical plug and the air
hose behind the flap and place the air
pump back in the trunk.
Close the trunk lid.
Drive away immediately.
The TIREFIT sealant will distribute itself
evenly inside the tire.
After driving vehicle for an initial
10 minutes, check tire pressure using
the pressure gauge on the air pump.Warning!
G
Do not exceed vehicle speed of 50 mph
(80 km / h). A TIREFIT repair is not designed
to operate at higher speeds.
The sticker must be attached on the instru-
ment cluster where it will be easily seen by
the driver.
Vehicle handling characteristics may
change. Adapt your driving accordingly.
Warning!
G
If tire pressure has fallen below
20 psi (1.3 bar) do not continue to drive the
vehicle.
Park your vehicle safely away from the road-
way and contact the nearest authorized
Mercedes-Benz Center or Roadside Assis-
tance.
If ti re pre ss ur e i s at l ea st 2 0 psi (1 .3 ba r ), in -
flate tire to correct pressure (see label on
fuel filler flap), and drive vehicle to nearest
tire repair facility to have tire repaired or re-
placed.
Recommended maximum duration of use:
300 miles (500 km) at 50 mph (80 km / h)
with the recommended tire pressure.
376 Practical hintsBatteries
Disconnecting the battery
Depress parking brake firmly or move
gear selector lever to positionP.
Turn off all electrical consumers.
Remove SmartKey from starter switch.
Vehicles with KEYLESS-GO*:
Press the start / stop button until
the engine shuts off.
Open the driver’s door.
Open the trunk.
!Never loosen or detach battery termi-
nal clamps while the engine is running
or the SmartKey is in the starter switch.
Otherwise the alternator and other
electronic components could be se-
verely damaged.
Have the battery checked regularly by
an authorized Mercedes-Benz Center.
Refer to Service Booklet for mainte-
nance intervals or contact your autho-
rized Mercedes-Benz Center for further
information.Warning!
G
Do not place metal objects on the battery as
this could result in a short circuit.
Use leak-proof battery only to avoid the risk
of acid burns in the event of an accident.
Warning!
G
The SBC brake system requires electrical
power to operate.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its emer-
gency operation mode. The same applies if
battery is disconnected. To brake, the driver
must then apply significantly greater brake
pedal pressure and depress the pedal much
further to obtain the expected braking ef-
fect. If necessary, apply full pressure to the
brake pedal. Brakes may only be applied to
the front wheels. Stopping distance is in-
creased! Adjust your driving style according-
ly. For more information, refer to “SBC brake
system” (
page 79).
Warning!
G
With a disconnected battery
you will no longer be able to turn the
SmartKey in the starter switch and
pressing the KEYLESS-GO* start/stop
button on the gear selector lever will
have no effect
the gear selector lever will remain
locked in positionP
382 Practical hintsTowing the vehicle
!
To be certain to avoid a possibility of
damage to the drive train, however, we
recommend the drive shaft be discon-
nected at the rear axle drive flange (ve-
hicles with 4MATIC: disconnected at
the front and rear axle drive flanges) for
any towing beyond a short tow to a
nearby garage.
Warning!
G
If circumstances require towing the vehicle
with all wheels on the ground, always tow
with a tow bar if:
the engine will not run
there is a malfunction in the SBC brake
system
there is a malfunction in the power sup-
ply or in the vehicle’s electrical system
as that will be necessary to adequately con-
trol the towed vehicle.
Prior to towing the vehicle with all wheels on
the ground, make certain that the SmartKey
is in starter switch position2.
If the SmartKey is left in the starter switch
position0 for an extended period of time, it
can no longer be turned in the switch. In this
case, the steering is locked. To unlock, re-
move SmartKey from starter switch and re-
insert.
Warning!
G
The brake system requires electrical power
to operate.
A malfunction in the vehicle’s power supply
or electrical system may impair brake sys-
tem operation and switch it into its emer-
gency operation mode. To brake, the driver
must then apply significantly greater brake
pedal pressure and depress the pedal much
further to obtain the expected braking ef-
fect. If necessary, apply full pressure to the
brake pedal. Brakes may only be applied to
the front wheels. Stopping distance is in-
creased! Adapt your driving style according-
ly. For more information, refer to “SBC brake
system” (
page 79).
With the engine not running, there is no
power assistance for the steering system. In
this case, it is important to keep in mind that
a considerably higher degree of effort is nec-
essary to steer the vehicle. Adapt your driv-
ing accordingly.
383 Practical hints
Towing the vehicle
iTo signal turns while being towed with
the hazard warning flasher in use, turn
SmartKey in starter switch to
position2 and activate the combina-
tion switch for the left or right turn sig-
nal in the usual manner – only the
selected turn signal will operate.
Upon canceling the turn signal, the haz-
ard warning flasher will operate again.
!When towing the vehicle with all wheels
on the ground, please note the follow-
ing:
With the automatic central locking acti-
vated and the SmartKey in starter
switch position2, or KEYLESS-GO*
start / stop button in position2, the ve-
hicle doors lock if the left front wheel
as well as the right rear wheel are turn-
ing at vehicle speeds of approximately
9 mph (15 km / h) or more.
Switch off the tow-away alarm
(page 85).
To prevent the vehicle door locks from
locking, deactivate the automatic cen-
tral locking (
page 106).
Towing of the vehicle should only be
done using the properly installed tow-
ing eye bolt. Never attach tow cable,
tow rope or tow rod to the vehicle chas-
sis, frame or suspension parts.
iThe selector lever will remain locked in
positionP and the SmartKey will not
turn in the starter switch if the battery
is disconnected or discharged. See
notes on the battery (
page 375) or
on jump starting (
page 378).
Manual unlocking transmission selec-
tor lever (
page 357).