Page 383 of 474
382 Practical hintsReplacing SmartKey batteriesIf 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.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 changing batteries, always
replace both batteries.
The required replacement batteries are
available at any Mercedes-Benz
Center.
Page 384 of 474
383
Practical hints
Replacing SmartKey batteries
SmartKey
Replacement batteries: Lithium, type
CR 2025 or equivalent.
Remove mechanical key
1
(page 377).
1 Mechanical key
2 Battery compartment
Insert mechanical key 1 in side
opening and push grey slide.
Battery compartment 2 is unlatched.
Pull the battery compartment 2 out of
the key housing in direction of arrow.
Remove the batteries.
3 Battery
4 Contact spring
Using a lint-free cloth, insert new
batteries 3 under contact spring 4
with the plus (+) side facing up.
Return battery compartment into the
housing until it locks in place.
Slide mechanical key 1 back into the
SmartKey.
Check the operation of the SmartKey.
Page 402 of 474
401
Practical hints
Battery
Battery
The battery is located in the engine com-
partment on the right hand side.
1 Clamps
Removing filter box
Release clamps 1.
Remove filter box.
Installing filter box
Insert filter box properly.
Secure it with clamps 1.
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 297).
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.
Page 403 of 474
402 Practical hintsBattery1Negative terminal
2 Positive terminal cover
Disconnecting the battery
Turn off the engine (
page 58).
Turn off all electrical consumers.
Remove SmartKey from starter switch.
Open the hood (
page 291).
Read and observe safety instructions
and precautions (
page 297).
Remove the filter box (
page 401).
Disconnect battery negative lead from
negative terminal 1.
Remove cover 2 from the positive
terminal.
Disconnect the battery positive lead.
Removing the battery
Remove the screw-nuts securing the
battery.
Remove the battery bracket.
Take out the battery.
Charging and reinstalling 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.
Warning!
G
With a disconnected battery
you will no longer be able to turn the
SmartKey in the starter switch
the gear selector lever will remain
locked in position P
Page 404 of 474
403
Practical hints
Battery
Reconnecting the battery
Turn off all electrical consumers.
Remove SmartKey from the starter
switch.
Connect the positive lead and fasten its
cover
2 (
page 402).
Connect the negative lead.
Reinstall the filter box (
page 401).
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 139) (vehi-
cles with COMAND*: see COMAND
operator’s manual).
Resynchronize side windows
(page 240).
Resynchronize panorama roof with
power tilt/sliding panel*
(page 246).
Page 405 of 474
404 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 an 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 may only be performed
on the battery installed in the engine
compartment.
Avoid repeated and lengthy starting
attempts.
Do not attempt to start the engine
using a battery quick charge unit.
If 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 and
may present a fire risk.
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 406 of 474
405
Practical hints
Jump starting
The battery is located in the engine com-
partment on the right hand side. The
terminals for jump starting are located in
front of the battery.
Make sure the two vehicles do not
touch.
Turn off the engine.
On both vehicles:
Turn off all electrical consumers.
Apply parking brake.
Shift gear selector lever to position P
(manual transmission to Neutral). 1
Positive terminal of charged battery
2 Positive under hood terminal in front of
discharged battery
3 Negative terminal of charged battery
4 Negative under hood terminal in front
of discharged battery
Connect positive terminal 1 of the
charged battery with positive under
hood terminal 2 in front of the dis-
charged battery with the jumper ca-
bles. Clamp cable to charged
battery 1 first.
Start engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminal 3 of the
charged battery with negative under
hood terminal 4 in front of the dis-
charged battery with the jumper
cables. Clamp cable to charged
battery 3 first.
Start the engine of the disabled
vehicle.
Now you can turn on the electrical con-
sumers. Do not turn on the lights under
any circumstances.
Remove the jumper cables first from
negative terminals 4 and 3 and then
from positive terminals 2 and 1.
You can now turn on the lights.
Have the battery checked at the
nearest 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 297).
!Vehicles with automatic transmission:
Do not tow-start the vehicle.
Page 409 of 474
408 Practical hintsTowing the vehicleWarning!
G
With the engine not running, there is no
power assistance for the brake and steering
systems. In this case, it is important to keep
in mind that a considerably higher degree of
effort is necessary to brake and steer the ve-
hicle. Adapt your driving accordingly.
!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, the vehicle doors
lock if the left front wheel as well as the
right rear wheel are turning at vehicle
speeds of approximately 9 mph
(15 km/h) or more.
Switch off the tow-away alarm
(page 87).
To prevent the vehicle doors from lock-
ing, deactivate the automatic central
locking (
page 148).
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 vehicle chassis,
frame or suspension parts.
iIf the battery is disconnected or dis-
charged
the SmartKey will not turn in the
starter switch. For more informa-
tion, see “Battery” (
page 401)
and “Jump starting” (page 404).
the gear selector lever will remain
locked in position P. For informa-
tion on manually unlocking trans-
mission gear selector lever, see
(page 380).
