Page 359 of 434

358 Practical hintsBatteries
BatteriesYour vehicle is equipped with two 
batteries:
The starter battery (located in the en-
gine compartment)
The battery for electrical consumers 
(located in the trunk)
Starter battery in the engine compartment1Positive terminal
2Negative terminal
Warning!
G
Failure to follow these instructions can re-
sult in severe injury or death.
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 starter battery checked regu-
larly by an authorized Mercedes-Benz 
Center.
Refer to Service Booklet for mainte-
nance intervals or contact an autho-
rized Mercedes-Benz Center for further 
information. 
     
        
        Page 362 of 434

361 Practical hints
Batteries
Removing the batteries
Removing the battery for electrical con-
sumers
Remove the screws securing the bat-
tery in the trunk.
Remove the battery support and brack-
et. Take out the battery.
Removing the starter battery
Remove the screws securing the start-
er battery in the engine compartment.
Lift the retaining bracket and remove 
the battery.
Charging and reinstalling batteries
Charge batteries 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 batteries
Reconnecting the starter battery
Turn off all electrical consumers.
Connect the positive lead and fasten its 
cover.
Connect the negative lead.
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.
!To avoid damage to electrical compo-
nents, always reconnect the starter 
battery (in engine compartment) first. !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. 
     
        
        Page 363 of 434
362 Practical hintsBatteriesReconnecting the battery for electrical 
consumers
Turn off all electrical consumers.
Connect the positive lead and fasten its 
cover.
Connect the negative lead.
Reinstall the trunk floor.
Rehook trunk luggage cover into hold-
ers.
!Never invert the terminal connections!iThe following procedures must be car-
ried out following any interruption of 
battery power (e.g. due to reconnec-
tion):
Resynchronize the ESP 
(page 295).
Resynchronize side windows 
(page 183). 
     
        
        Page 364 of 434

363 Practical hints
Jump starting
Jump starting
If the starter battery is discharged, the en-
gine can be started with jumper cables and 
the battery of another vehicle. Observe the 
following:
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.
Only use jumper cables with sufficient 
cross section and insulated terminal 
clamps.
Always make sure the jumper cables 
are not on or near pulleys, fans, or oth-
er 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 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 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 365 of 434

364 Practical hintsJump startingThe starter battery is located on the right 
side of 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.
Remove the red cover from positive ter-
minal on both vehicles (
page 358).1Negative terminal of charged battery
2Negative terminal of discharged 
battery
3Positive terminal of discharged battery
4Positive terminal of charged battery
Connect positive terminals 3 and 4 
of the batteries with the jumper cables. 
Clamp cable to charged battery 4 
first.
Start the engine of the vehicle with the 
charged battery and run at idle speed.
Connect negative terminals 1 and 2 
of the batteries with the jumper cables. 
Clamp cable to charged battery 1 
first.
Start the engine of the disabled vehi-
cle.
You can now turn on the electrical con-
sumers. Do not turn on the lights under 
any circumstances.
Remove the jumper cables first from 
negative terminals 1 and 2 and then 
from positive terminals 3 and 4.
You can now turn on the lights.
Have the battery checked at the near-
est 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 260).
!Never invert the terminal connections.
!Do not tow-start the vehicle.