411 Practical hints
Flat tire
Turn the SmartKey in the starter switch
to position1.
or
Press the KEYLESS-GO* start/stop
button on the gear selector lever once
without depressing the brake pedal.
PressI on the electric air pump
switch2.
The electric air pump should now
switch on and inflate the tire.
Inflate the spare tire:
SL 550 to 36 psi (2.5 bar)
SL 600, SL 55 AMG, SL 55 AMG
(Performance Package*), and
SL 65 AMG to 51 psi (3.5 bar)
This takes about 5 minutes.
Air hose4 and union nut5 can be-
come hot during inflation. Exercise
proper caution to avoid burning your-
self when using the equipment.
Press0 on the electric air pump
switch2.
Turn the SmartKey in the starter switch
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 spare tire inflation pressure is
above the recommended tire inflation
pressure for the respective collapsible
tire (
page 440), release excess spare
tire inflation pressure using the vent
screw.
Detach the electric air pump.
Stow the electrical plug and the air
hose behind the flap and place the air
pump back in the trunk.
!
Compare the recommended tire inflation
pressure for your vehicle with the tire inflation
pressure on the yellow label located on the spare
wheel rim.
If the tire inflation pressure on the yellow label
on the spare wheel rim differs from the values
given in this Operator’s Manual, inflate the tire to
the recommended tire inflation pressure given
on the yellow label on the spare wheel rim.
!
Do not operate the electric air pump longer
than 8 minutes without interruption. Otherwise it
may overheat.
You may operate the air pump again after 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.
414 Practical hintsBatteriesFor more information on batteries, see
“Battery” (
page 281).
Your vehicle is equipped with two
batteries:
The starter battery
The battery for electrical consumers
(consumer battery), located in the
trunk
The starter battery is located on the
right-hand side of the engine compart-
ment.
1Positive terminal
2Negative terminal
3Battery ventilationThe consumer battery is located on the
right-hand side of the trunk.
4Positive terminal
5Negative terminal
!
The starter battery, its filler caps, and the
ventilation hose must always be securely in-
stalled when the vehicle is in operation.
!
The consumer battery located in the trunk is
a valve-regulated lead acid (VRLA) battery, also
referred to as “fleece” battery. Such batteries do
not require topping-up of the electrolyte level.
VRLA batteries therefore do not have cell caps
and the battery cover is non-removable. Do not
attempt to open the consumer battery as other-
wise the battery will be damaged.
Even though VRLA batteries do not require top-
ping-up of the electrolyte level and cannot be
opened to check the electrolyte level, the bat-
tery condition must be checked periodically by
performing a battery conductance test. Refer to
Maintenance Booklet for battery condition test-
ing intervals.
As with any other battery, disconnect the con-
sumer battery if you do not intend to operate
your vehicle for an extended period of time to
prevent battery discharge or connect an acces-
sory battery charge unit expressly approved by
Mercedes-Benz for your vehicle model to main-
tain the battery charge. Contact an authorized
Mercedes-Benz Center for further information.
415 Practical hints
Batteries
!
The factory-equipped VRLA battery is
leak-proofed. Only use a battery as replacement
that has the same security features and is of
identical size, voltage, and capacity as the
factory-equipped battery.
The battery, the battery ventilation and the later-
al plug must always be securely installed when
the vehicle is in operation.
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 terminal
clamps while the engine is running or the
SmartKey is in the starter switch. Otherwise the
alternator and other electronic components
could be severely damaged.
Have the starter battery checked regularly by an
authorized Mercedes-Benz Center.
Refer to Maintenance Booklet for maintenance
intervals or contact an authorized
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 batteries only to avoid the
risk of acid burns in the event of an acci-
dent.
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. 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 are only applied to the
front wheels. Stopping distance is in-
creased! Adjust your driving style according-
ly. For more information, see
“Electro-hydraulic brake system”
(page 92).
416 Practical hintsBatteries
Disconnecting the batteries
Apply the parking brake (
page 61).
Make sure the gear selector lever is set
to position P (
page 168).
Close the retractable hardtop
(page 199).
Turn off all electrical consumers.
Turn off the engine (
page 62).
Remove the SmartKey from the starter
switch.
Vehicles with KEYLESS-GO*: Open
the driver’s door.
Open the trunk.
Read and observe safety instructions
and precautions (
page 281).
Open the luggage cover in the trunk
(page 206).
Remove the trunk floor.
The battery for electrical consumers is
located in the right hand area of the
trunk (
page 388).
Use the 10 mm open-end wrench from
the vehicle tool kit to disconnect the
negative lead from negative
terminal5 of the consumer battery
(page 414).
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
!
Always disconnect the batteries in the order
described below, even if you only want to charge
the starter battery, for example. Otherwise the
vehicle’s electronics can be damaged.
418 Practical hintsBatteries
Charge batteries in accordance with
the instructions of the battery charger
manufacturer.
Reinstall the charged batteries. Follow
the previously described steps in re-
verse order.
Reconnecting the batteries
Turn off all electrical consumers.
Install starter battery in the designated
location in the engine compartment.
Install consumer battery in the desig-
nated location in the trunk.
Attach supports and brackets.
Tighten support and bracket screws.
Connect positive lead 4 (
page 414)
of the consumer battery and positive
lead 1 (
page 414) of the starter bat-
tery and fasten covers.
Connect negative lead 2
(page 414) of the starter battery.
Connect negative lead 5
(page 414) of the consumer battery.
Reinstall the trunk floor.
Close trunk luggage cover
(page 206).
!
Always connect the batteries in the order
described below. Otherwise the vehicle’s elec-
tronics can be damaged.
!
Never invert the terminal connections!
i
The following procedures must be carried
out following any interruption of battery power
(e.g. due to reconnection):
Resynchronize the ESP
® (page 355).
Resynchronize side windows (
page 198).
419 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
converter 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
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.
!
Do not tow-start the vehicle.
!
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 bat-
tery quick charge unit.
If the engine does not run after several unsuc-
cessful 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.
420 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 the parking brake (
page 61).
Make sure the gear selector lever is set
to position P (
page 168).
Open the hood (
page 274).
Remove the red cover from positive ter-
minal on both vehicles (
page 414).1Positive terminal of charged battery
2Positive terminal of discharged battery
3Negative terminal of discharged
battery
4Negative terminal of charged battery
Connect positive terminals 1 and 2
of the batteries with the red jumper ca-
ble. Clamp cable to charged battery 1
first.
Start the engine of the vehicle with the
charged battery and run at idle speed.
Connect negative terminals 3 and 4
of the batteries with the black jumper
cable. Clamp cable to charged
battery3 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 4 and 3 and then
from positive terminals 2 and 1.
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 281).
!
Never invert the terminal connections.
421 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.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 only so far as
necessary to have the vehicle moved to a
safe location where the recommended
towing methods can be employed.!
Use flatbed or wheel lift/dolly equipment
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.
!
If the vehicle is towed with the front axle
raised, the gear selector lever must be in
positionN and the engine must be shut off
(SmartKey in starter switch position0 or1).
Otherwise, the ESP
® will immediately be en-
gaged and will apply the rear wheel brakes.
When towing the vehicle with all wheels on the
ground, the gear 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 distances up to
30 miles (50 km) and at a speed not to exceed
30 mph (50 km/h).
To be certain to avoid a possibility of damage to
the transmission, however, we recommend the
drive shaft be disconnected at the rear axle drive
flange 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
electro-hydraulic 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 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.