Page 425 of 491
424 Practical hintsBatteriesYour vehicle is equipped with two batter-
ies:
Main battery (battery for starter and
electrical consumers; located in the
cargo compartment).
Auxiliary battery (back-up battery; sta-
bilizes the electrical system if the main
battery is discharged; located in the en-
gine compartment).
Pull cover up and detach it.1Negative terminal
2Positive terminaliThe battery is located on the right-hand
side under a cover.
Warning!
G
Jump starting must only be done using the
designated terminal connections in the en-
gine compartment (
page 429).
Page 426 of 491

425 Practical hints
Batteries
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 305).
Never lean over batteries while connecting,
you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking etc.
!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 an 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 92).
Page 427 of 491

426 Practical hintsBatteriesDisconnecting 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 tailgate.
Read and observe safety instructions
and precautions (
page 425).
Access the cargo compartment under-
neath the third row seat cushions and
footwell (
page 401).
Remove cover to access battery
(page 424).
Disconnect battery negative lead1.
Remove cover2 from the positive ter-
minal.
Disconnect the battery positive lead.
Removing the battery
Remove the screw-nuts securing the
battery.
Remove the battery bracket.
Take out the battery.
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 428 of 491

427 Practical hints
Batteries
Charging and reinstalling the battery
Charge battery in accordance with the
instructions of the battery charger
manufacturer.
Reinstall the charged battery. Follow
the previously described steps in re-
verse order.
Reconnecting the battery
Turn off all electrical consumers.
Connect the positive lead and fasten its
cover.
Connect the negative lead.
Batteries contain materials that can harm
the environment if disposed of improperly.
Large 12 volt storage batteries contain
lead. Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
Warning!
G
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 charg-
ing and cause explosions that may result in
paint damage, corrosion or personal injury.
An accessory battery charge unit* specially
adapted for Mercedes-Benz vehicles and
tested and approved by Mercedes-Benz is
available, permitting the charging of the bat-
tery in its installed position. Contact an au-
thorized Mercedes-Benz Center for
information and availability. Charge battery
in accordance with the instructions for the
accessory battery charger*.
!Never invert the terminal connections!!The battery, its filler caps and the vent
tube must always be securely installed
when the vehicle is in operation.
iThe following procedures must be car-
ried out following any interruption of
battery power (e.g. due to reconnec-
tion):
Set the clock (
page 167)
(see COMAND operator’s manual).
Resynchronize the ESP
(page 367).
Resynchronize the side windows
(page 223).
Resynchronize the tilt / sliding sun-
roof* (
page 227).
Page 429 of 491

428 Practical hintsJump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:
Jump starting should only be performed
when the engine and catalytic convert-
er are cold.
Do not start the engine if the battery is
frozen. Let the battery thaw out first.
Only jump start from batteries with the
same voltage rating (12 V). Jump start-
ing with a more powerful battery could
damage the vehicle’s electrical system,
which will not be covered by the
Mercedes-Benz Limited Warranty.
Use only jumper cables with sufficient
cross-section and insulated terminal
clamps.
Always make sure the jumper cables
are not on or near pulleys, fans or other
parts that move when the engine is
started or running.
Warning!
G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water, and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
!Jump starting of the main battery must
only be done using the designated
jump start terminals located in the
engine compartment (
page 429).
Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine us-
ing a battery quick charge unit.
If the engine does not run after several
unsuccessful starting attempts, have it
checked at the nearest authorized
Mercedes-Benz Center.
Excessive unburned fuel generated by
repeated failed starting attempts may
damage the catalytic converter.
Make sure the jumper cables do not
have loose or missing insulation.
Make sure the cable clamps do not
touch any other metal part while the
other end is still attached to a battery.
Page 430 of 491

429 Practical hints
Jump starting
The jump-start contacts are located in the
engine compartment.
Make sure the two vehicles do not
touch.
Turn off all electrical consumers.
Apply parking brake.
Shift gear selector lever to positionP.1Negative (-) terminal
2Cover of Positive (+) terminal
Open cover 2 of the positive terminal
of both vehicles.
Connect positive terminal 2 and the
positive terminal of the charged battery
with the jumper cable. Clamp cable to
charged battery first.
Start engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminal1 and the
negative terminal of the charged
battery with the jumper cable. Clamp
cable to charged battery first.
Start the engine of the disabled
vehicle.
Now you can again turn on the electrical
consumers. Do not turn on the lights under
any circumstances.
Remove the jumper cables first from
negative terminals1 and then from
the positive terminals2.
Now you can turn on the lights.
Have the battery checked at the near-
est authorized Mercedes-Benz Center.
Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 305).!Never invert the terminal connections!
iThe message
Malfunction - electric
consumers switched off
may appear
in the instrument cluster. It will disap-
pear as soon as the battery is suffi-
ciently charged.
!Do not tow-start the vehicle.
Page 431 of 491

430 Practical hintsTowing the vehicleMercedes-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 432 of 491

431 Practical hints
Towing 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 sure 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 92).
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.