Page 435 of 506
433 Practical hints
Batteries
Batteries
Your vehicle is equipped with two batter-
ies:
Main battery (battery for starter and
electrical consumers; located in the
trunk).
Auxiliary battery (back-up battery; sta-
bilizes the electrical system if the main
battery is discharged; located in the en-
gine compartment)
The main battery is in the trunk under the
luggage box. Remove the luggage box
(
page 408).
Vehicles with spare wheel1Negative terminal
2Positive terminalWarning!
G
Jump starting must only be done using the
main battery in the trunk.
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 309).
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.
Page 437 of 506
435 Practical hints
Batteries
Remove the luggage box (
page 408).
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.
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.
Install the luggage box (
page 408).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. Gases may escape during charg-
ing and cause explosions that may result in
paint damage, corrosion or personal injury.
!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 159)
(see COMAND operator’s manual).
Resynchronize the ESP
(page 372).
Resynchronize the side windows
(page 220).
Resynchronize the tilt/sliding sun-
roof* (
page 225) or the tilt/slid-
ing panel* (
page 229).
Page 438 of 506
436 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-
er1 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.
1Vehicles with gasoline engine only
!Jump starting may only be performed
on the main battery installed in the
trunk.
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 converter1.
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 439 of 506
437 Practical hints
Jump starting
The battery is located in the trunk under-
neath the luggage box (
page 408). Only
jump start the vehicle from the battery in
the trunk.
Make sure the two vehicles do not
touch.
Turn off all electrical consumers.
Apply parking brake.
Shift gear selector lever to positionP.
Connect positive terminals1 and3
of the batteries with the jumper cable.
Clamp cable to charged battery3
first.
1Positive terminal of discharged battery
2Negative terminal of discharged bat-
tery
3Positive terminal of charged battery
4Negative terminal of charged battery
Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 309).
!Never invert the terminal connections!
Page 440 of 506
438 Practical hintsJump starting
Start engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminals4 and2
of the batteries with the jumper cable.
Clamp cable to charged battery4
first.
Start the engine of the disabled vehi-
cle.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 terminals2 and4 and then
from positive terminals1 and3.
Now you can turn on the lights.
Have the battery checked at the near-
est authorized Mercedes-Benz Center.
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.
