Page 417 of 506

415 Practical hints
Replacing SmartKey batteries
Replacing SmartKey batteries
If the batteries in the SmartKey are dis-
charged, the vehicle can no longer be
locked or unlocked. It is recommended to
have the batteries replaced at an autho-
rized Mercedes-Benz Center.
Batteries contain materials that can harm
the environment if disposed of improperly.
Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
SmartKey
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove the mechanical key1
(page 410).
1Mechanical key
2Battery compartment
Insert the mechanical key1 in side
opening and push gray slide.
Battery compartment2 is unlatched.
Pull battery compartment2 out of the
housing in direction of arrow.
Remove the batteries.
Warning!
G
Keep the batteries out of reach of children.
If a battery is swallowed, seek medical help
immediately.
iWhen inserting the batteries, make
sure they are clean and free of lint.iWhen replacing batteries, always re-
place both batteries.
The required replacement batteries are
available at any Mercedes-Benz Cen-
ter.
Page 418 of 506
416 Practical hintsReplacing SmartKey batteries3Battery
4Contact spring
Using a lint-free cloth, insert new bat-
teries under the contact spring with the
plus (+) side facing up.
Return battery compartment into hous-
ing until it locks into place.
SmartKey with KEYLESS-GO*
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove mechanical key (
page 410).
1Battery
2Tilt battery up
3Mechanical key
Insert the mechanical key3 in side
opening and push grey slide.
Battery compartment is unlatched.
Pull battery compartment out of the
housing in direction of arrow.
Using mechanical key3 apply pres-
sure to position2.
Battery1 tilts up slightly.
Pull out batteries1 in direction of ar-
row.
Using a lint-free cloth, insert new bat-
teries with the plus (+) side facing up.
Return battery compartment into hous-
ing until it locks into place.
Page 425 of 506
423 Practical hints
Replacing wiper blades
Replacing wiper blades
Removing wiper blades
Turn SmartKey in starter switch to
position1.
Turn combination switch to wiper
settingII (
page 51).
With wiper arm in the vertical position,
turn SmartKey in starter switch to
position0.
Fold the wiper arm forward until it
snaps into place.
Turn the wiper blade at a right angle to
wiper arm.
Slide the wiper blade sideways out of
the retainer.
!The windshield wipers must be in a ver-
tical position before folding them away
from the windshield. They could other-
wise damage the hood.
Warning!
G
For safety reasons, switch off wipers and re-
move SmartKey from starter switch (vehi-
cles with KEYLESS-GO*: make sure the
vehicle's on-board electronics have status
0) before replacing a wiper blade. Other-
wise, the wiper motor could suddenly turn
on and cause injury.
Page 432 of 506

430 Practical hintsFlat tire
Screw air hose 4 onto the tire valve.
Insert electrical plug 3 into vehicle ci-
gar lighter socket.
Turn the SmartKey in the ignition to
position1.
or
Press the KEYLESS-GO* start/stop
button on the gear selector lever once
without depressing the brake pedal.
Press I on electric air pump switch 2.
The electric air pump should now
switch on and inflate the tire.
Inflate the tire to approx. 51 psi
(3.5 bar).
This takes about five minutes for the
collapsible tire. Air hose 4 and union
nut5 can become hot duration infla-
tion. Exercise proper caution to avoid
burning yourself when using the equip-
ment.
Press 0 on electric air pump switch 2.
Turn the SmartKey in the ignition to
position0.
or
Press KEYLESS-GO* start/stop button
on the gear selector lever twice without
depressing the brake pedal.
The electric air pump should now be
switched off.
If the tire inflation pressure is above
51 psi (3.5 bar), release excess tire in-
flation pressure using the vent screw.
Detach the electric air pump.
Stow electrical plug 3 and air hose 4
behind flap 1 and place the air pump
back in the trunk.
!Do not operate the air pump longer
than eight minutes without interrup-
tion. Otherwise it may overheat.
You may operate the air pump again af-
ter it has cooled off.
Warning!
G
Follow recommend inflation pressures.
Do not overinflate tires. Overinflating tires
can result in sudden deflation (blowout) be-
cause they are more likely to become punc-
tured or damaged by road debris, potholes,
etc.
Do not underinflate tires. Underinflated tires
wear unevenly, adversely affect handling
and fuel economy, and are more likely to fail
from being overheated.
Page 434 of 506

432 Practical hintsBleeding the fuel system (Diesel engine only)Allowing the vehicle to be driven until the
fuel tank is empty is not recommended. If
this occurs, air may be pulled into the fuel
system. If this happens, the? malfunc-
tion indicator lamp (USA only) or the
±malfunction indicator lamp (Canada
only) comes and it may be possible that
the engine will not start immediately after
you refuel the vehicle.
After refueling:
Turn the SmartKey in the starter switch
to position2 for at least 30 seconds.
Return the SmartKey in the starter
switch to position0.
Turn the SmartKey in the starter switch
to position3 and hold it there for up to
60 seconds, i.e. until the engine is run-
ning surge-free.If the engine does not start:
Try to start the engine again without in-
terruption for a maximum of 60 sec-
onds until it is running smoothly.
If the engine still does not start even after
this attempt, do not make any further at-
tempts to start the engine. Contact an
authorized Mercedes-Benz Center.
iWhere the? malfunction indicator
lamp (USA only) or the± malfunc-
tion indicator lamp (Canada only) in the
instrument cluster has been illuminat-
ed for the above condition, it will re-
main illuminated until the engine was
cycled on and off four times in a row.
Page 436 of 506

434 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 Maintenance Booklet for main-
tenance intervals or contact your au-
thorized 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 90).
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
Page 441 of 506

439 Practical hints
Towing the vehicle
Towing the vehicle
Mercedes-Benz recommends that the vehi-
cle be transported with all wheels off the
ground using flatbed or appropriate wheel
lift/dolly equipment. This method is pref-
erable to other types of towing.When circumstances do not permit the
recommended towing methods, the vehi-
cle may be towed with all wheels on the
ground or front wheels raised (except vehi-
cles with 4MATIC) only so far as necessary
to have the vehicle moved to a safe loca-
tion where the recommended towing
methods can be employed.
!Use flatbed or wheel lift/dolly equip-
ment with SmartKey in starter switch
turned to position0.
Do not tow with sling-type equipment.
Towing with sling-type equipment over
bumpy roads will damage radiator and
supports.
To prevent damage during transport,
do not tie down vehicle by its chassis or
suspension parts.
Switch off the tow-away alarm and the
automatic central locking
Do not tow-start the vehicle.
!Vehicles with 4MATIC:
Do not tow with one axle raised. Doing
so could damage the transfer case,
which is not covered by the
Mercedes-Benz Limited Warranty.
All wheels must be on or off the ground.
Observe instructions for towing the ve-
hicle with all wheels on the ground.
!If the vehicle is towed with the front
axle raised (not permissible for vehicles
with 4MATIC), the engine must be shut
off (SmartKey in starter switch
position0 or 1). Otherwise the ESP will
immediately be engaged and will apply
the rear wheel brakes.
When towing the vehicle with all wheels
on the ground, the selector lever must
be in positionN and the SmartKey
must be in starter switch position2.
When towing the vehicle with all wheels
on the ground or the front axle raised,
the vehicle may be towed only for dis-
tances up to 30 miles (50 km) and at a
speed not to exceed 30 mph
(50 km/h).
Page 442 of 506

440 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 90).
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.