engine MERCEDES-BENZ SL ROADSTER 2012 Owners Manual

ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not inhale any battery gases. Do not lean
over the battery. Keep children away from
batteries. Wash battery acid immediately with water and seek medical attention. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only charge the installed battery with a
battery charger which has been tested and
approved by Mercedes-Benz. These battery chargers allow the battery to be charged
while still installed in the vehicle.
! Only use battery chargers with a maxi-
mum charging voltage of 14.8 V.
! Only
charge the battery using the jump-
start connection point.
The jump-starting connection point is in the
engine compartment.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the
discharged battery has frozen. In this case
you may neither jump-start the vehicle nor
charge the battery. The service life of a bat-
tery that has been thawed may be reduced.
The starting characteristics may be impaired,
especially at low temperatures. Have the
thawed battery checked at a qualified spe-
cialist workshop.
Read the battery charger's operating instruc- tions before charging the battery. X
Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order
as when connecting the donor battery in
the jump-starting procedure
(Y page 586). Battery (vehicle)
585Breakdown assistance Z

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a positive terminal and an earth point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the battery. Keep children away from batteries. Wash battery acid immediately with water and seek
medical attention. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jump leads.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
! Avoid repeated and lengthy starting attempts. Otherwise, the catalytic converter could be
damaged by the non-combusted fuel.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the
discharged battery has frozen. In this case you may neither jump-start the vehicle nor charge
the battery. The service life of a battery that has been thawed may be reduced. The starting
characteristics may be impaired, especially at low temperatures. Have the thawed battery
checked at a qualified specialist workshop. 586
Jump-startingBreakdown assistance

Do not use a rapid charging device to start the vehicle. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a second battery using jump
leads. Observe the following points:
R The battery is not accessible in all vehicles. If the other vehicle's battery is not accessible,
jump-start the vehicle using a second battery or a jump-starting device.
R You may only jump-start the vehicle when the engine and exhaust system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Jump-starting may only be performed from batteries with a nominal voltage of 12 V.
R Only use jump leads that have a sufficient cross-section and insulated terminal clamps.
R If the battery is fully discharged, leave the battery that is being used to jump-start connected
for a few minutes before attempting to start. This charges the empty battery a little.
R Make sure that the two vehicles do not touch.
Make sure that:
R The jump leads are not damaged.
R Non-insulated parts of the terminal clamps do not come into contact with other metal parts
while the jump leads are connected to the battery.
R The jump leads cannot come into contact with parts which can move when the engine is
running, such as the V-belt pulley or the fan.
X Secure the vehicle by applying the electric parking brake.
X Shift the transmission to position P.
X Turn the key to position 0in the ignition lock and remove it (Y page 155). On vehicles with
KEYLESS-GO, make sure the ignition is switched off (Y page 155). All indicator lamps in the
instrument cluster must be off.
X Switch off all electrical consumers, e.g. rear window heating, lighting etc.
X Open the bonnet. Jump-starting
587Breakdown assistance Z

Position number
Bidentifies the charged battery of the other vehicle or an equivalent jump-
starting device.
X Press cover :of positive terminal ;down (in the direction of the arrow) and turn it
clockwise. Cover :is held down in the lowered position, which exposes positive termi-
nal ;.
X Connect positive terminal ;on your vehicle to positive terminal =of donor battery B
using the jump lead. Always begin with positive terminal ;on your own vehicle first.
X Start the engine of the donor vehicle and run it at idling speed.
X Connect negative terminal ?of donor battery Bto earth point Aof your vehicle using the
jump lead, connecting the jump lead to donor battery Bfirst.
X Start the engine.
X Before disconnecting the jump leads, let the engines run for several minutes.
X First, remove the jump leads from earth point Aand negative terminal ?, then from pos-
itive clamp ;and positive terminal =. Begin each time at the contacts on your own vehicle
first.
X After removing the jump leads, press down cover :of positive terminal ;and turn it anti-
clockwise. Cover :returns to its original position. Positive terminal ;is covered up and
thus insulated again.
X Have the battery checked at a qualified specialist workshop.
i Jump-starting is not considered to be a normal operating condition.
i Jump-starting cables and further information regarding jump starting can be obtained at
any qualified specialist workshop. Towing and tow-starting
Important safety notes
G
WARNING
If the weight of the vehicle to be towed or tow- started is greater than the permissible gross
weight of your vehicle:
R the towing eye could detach itself
R the vehicle/trailer combination could over-
turn.
There is a risk of an accident.
When towing or tow-starting another vehicle,
its weight should not be greater than the per-
missible gross weight of your vehicle. !
If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow- ing or other similar situations:
R when towing the vehicle
R in the car wash
! Only secure the tow rope or towing bar to
the towing eyes. The vehicle may otherwise be damaged.
! Observe the following points when towing
with a tow rope:
R secure the tow rope on the same side on
both vehicles.
R make sure that the tow rope is not longer
than legally permitted. Mark the tow rope in the middle, e.g. with a white cloth
(30 x 30 cm). This makes other road 588
Towing and tow-startingBreakdown assistance

X
Switch on the hazard warning lamps
(Y page 130).
X Turn the key in the ignition lock to position
0 and remove the key from the ignition
lock.
X When leaving the vehicle, take the key or
the KEYLESS-GO key with you.
When towing your vehicle with the rear axle
raised, it is important that you observe the
safety instructions (Y page 588).Towing the vehicle with both axles on
the ground G
WARNING
If the steering wheel lock is engaged, the vehi- cle can no longer be steered. There is a risk of
an accident.
Always switch on the ignition when towing
with a tow rope or a towing bar.
The automatic transmission automatically
shifts to position Pwhen you open the driver's
or front-passenger door or when you remove the key from the ignition lock.
In order to ensure that the automatic trans-
mission stays in position Nwhen towing the
vehicle, you must observe the following
points:
X Switch on the hazard warning lamps
(Y page 130).
i In order to signal a change of direction
when towing the vehicle with the hazard
warning lamps switched on, use the com-
bination switch as usual. In this case, only
the turn signals for the desired direction
flash. When the combination switch is
reset, the hazard warning lamps start flash- ing again.
X Make sure that the vehicle is stationary and
that the key is in position 0in the ignition
lock.
X Turn the key to position 2in the ignition
lock. On vehicles with KEYLESS-GO, use the key
instead of the Start/Stop button
(Y page 155).
X Depress and hold the brake pedal.
X Shift the automatic transmission to posi-
tion N.
X Release the brake pedal.
X Release the electric parking brake.
X Leave the key in position 2in the ignition
lock.
It is important that you observe the safety
instructions when towing away your vehicle
(Y page 588). Transporting the vehicle
! You may only secure the vehicle by the
wheels, not by parts of the vehicle such as
axle or steering components. Otherwise,
the vehicle could be damaged.
The towing eye can be used to pull the vehicle
onto a trailer or transporter for transport pur-
poses.
X Turn the key to position 2in the ignition
lock.
X Shift the automatic transmission to posi-
tion N.
As soon as the vehicle is loaded: X Prevent the vehicle from rolling away by
applying the electric parking brake.
X Shift the automatic transmission to posi-
tion P.
X Turn the key to position 0in the ignition
lock and remove it.
X Secure the vehicle. Tow-starting (emergency engine
starting)
! Do not tow-start vehicles with automatic
transmission. You could otherwise damage the automatic transmission. Towing and tow-starting
591Breakdown assistance Z

i
You can find information on "Jump-start-
ing" under (Y page 586). Electrical fuses
Important safety notes
G
WARNING
If you manipulate, bridge or replace a faulty
fuse with a fuse of a higher amperage, the
electric cables could be overloaded. This may result in a fire. There is a risk of an accident
and injury.
Always replace faulty fuses with specified new fuses of the correct amperage.
! Only use fuses that have been approved
for Mercedes-Benz vehicles and which
have the correct fuse rating for the system concerned. Otherwise, components or sys-
tems could be damaged.
The fuses in your vehicle serve to disconnect
faulty circuits. If a fuse blows, all the compo- nents on the circuit and their functions will
fail.
Blown fuses must be replaced with fuses of
the same rating, which you can recognise by
the colour and fuse rating. The fuse ratings
are listed in the fuse allocation chart.
If the newly inserted fuse also blows, have the
cause traced and rectified at a qualified spe-
cialist workshop, e.g. a Mercedes-Benz Ser-
vice Centre. Before replacing a fuse
X Secure the vehicle against rolling away
(Y page 175).
X Switch off all electrical consumers.
X Turn the key to position 0in the ignition
lock and remove it (Y page 155).
or
X On vehicles with KEYLESS-GO, make sure
the ignition is switched off (Y page 155).All indicator lamps in the instrument cluster
must be off.
The fuses are located in various fuse boxes:
R fuse box in the engine compartment on the
right-hand side of the vehicle, when viewed
in the direction of travel
R dashboard fuse box
R fuse box in the rear compartment on the
right-hand side of the vehicle, when viewed
in the direction of travel
The fuse allocation chart is located in the
vehicle tool kit in the stowage compartment
under the boot floor (Y page 577). Dashboard fuse box
i Observe the "Important safety notes" sec-
tion (Y page 592).
! Do not use a pointed object such as a
screwdriver to open the cover in the dash-
board. You could damage the dashboard or
the cover.
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses. X
To open: pull cover :outwards in the
direction of the arrow and remove it.
X To close: clip in cover :on the front of the
dashboard.
X Fold cover :inwards until it engages. 592
Electrical fusesBreakdown assistance

Fuse box in the engine compartment
i Observe the "Important safety notes" sec-
tion (Y page 592). G
WARNING
When the bonnet is open, and the windscreen wipers are set in motion, you can be injured by
the wiper linkage. There is a risk of injury.
Always switch off the windscreen wipers and
the ignition before opening the bonnet.
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture
seeping in or dirt could otherwise impair
the operation of the fuses.
X Open the bonnet. X
Remove any existing moisture from the
fuse box using a dry cloth.
X To open: open clamps ;.
X Fold cover :of the fuse box up in the
direction of the arrow and remove it. X
To close: check whether the seal is lying
correctly in cover :.
X Insert both openings =at the rear of
cover :into the brackets on the fuse box.
The brackets on the fuse box must be com-
pletely visible in the two openings =on the
fuse box.
X Fold down cover :.
X Hook clamps ;into the fuse box and
close.
X Close the bonnet. Fuse box in the rear
i Observe the "Important safety notes" sec-
tion (Y page 592).
! Make sure that no moisture can enter the
fuse box when the cover is open.
! When closing the cover, make sure that it
is lying correctly on the fuse box. Moisture seeping in or dirt could otherwise impair
the operation of the fuses. The fuse box in the rear is located on the right-hand
side when viewed in the direction of travel.
X To open: open the seat belt guide on the
right-hand seat and remove the seat belt
(Y page 115).
X Move the right-hand seat as far forward as
possible (Y page 115).
X Insert your fingers at the bottom of front
cover :between the cover and floor cov-
ering. Electrical fuses
593Breakdown assistance Z

Storing wheels
Store wheels that are not being used in a cool,
dry and preferably dark place. Protect the
tyres against oil, grease, petrol and diesel. Cleaning the wheels
G
WARNING
The water jet of circular-jet nozzles (dirt grind- ers) can cause damage not visible from the
outside to tyres or chassis components. Com-
ponents damaged in this way can unexpect-
edly fail. There is a risk of an accident.
Do not use high-pressure cleaners with circu-
lar-jet nozzles to clean the vehicle. Have dam- aged tyres or chassis components replaced
immediately. Fitting a wheel
Preparing the vehicle X
Stop the vehicle on solid, non-slippery and
level ground.
X Unload the vehicle. The jack can only be
used when the vehicle is unladen.
X Apply the electric parking brake manually.
X Move the front wheels to the straight-
ahead position.
X Shift the transmission to position P.
X Switch off the engine.
X Vehicles without KEYLESS-GO: remove
the key from the ignition lock.
X Vehicles with KEYLESS-GO: open the
driver's door.
The on-board electronics now have status
0. This is the same as the key having been
removed.
X Vehicles with KEYLESS-GO: remove the
Start/Stop button from the ignition lock
(Y page 155). X
If included in the vehicle equipment,
remove the tyre-change tool kit from the
vehicle.
X Secure the vehicle to prevent it from rolling
away.
i Apart from certain country-specific varia-
tions, vehicles are not equipped with a tyre-
change tool kit. For information on which
tools are required to perform a wheel
change on your vehicle, consult a
Mercedes-Benz Service Centre.
Necessary wheel-changing tools may
include, for example:
R jack
R wheel chock
R wheel wrench
Securing the vehicle against rolling
away If your vehicle is equipped with a wheel chock,
it can be found in the tyre-change tool kit
(Y page 577).
The folding wheel chock is an additional
securing measure to prevent the vehicle from
rolling away, for example when changing a
wheel.
X Fold both plates upwards :.
X Fold out lower plate ;.
X Guide the lugs on the lower plate fully into
the openings in base plate =.606
Changing a wheelWheels and tyres

Securing the vehicle on level ground
X On level ground: place chocks or other
suitable items under the front and rear of
the wheel that is diagonally opposite the
wheel you wish to change. Securing the vehicle on slight downhill gradients
X On light downhill gradients: place
chocks or other suitable items in front of
the wheels of the front and rear axle.
Raising the vehicle G
WARNING
If you do not position the jack correctly at the appropriate jacking point of the vehicle, the
jack could tip over with the vehicle raised.
There is a risk of injury.
Only position the jack at the appropriate jack-
ing point of the vehicle. The base of the jack
must be positioned vertically, directly under
the jacking point of the vehicle. The following must be observed when raising
the vehicle:
R to raise the vehicle, only use the vehicle-
specific jack that has been tested and
approved by Mercedes-Benz. If the jack is
used incorrectly, it could tip over while the
vehicle is raised.
R the jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed. It is not suitable for per-
forming maintenance work under the vehi- cle.
R avoid changing the wheel on uphill and
downhill slopes.
R before raising the vehicle, secure it from
rolling away by applying the parking brake
and positioning wheel chocks. Never
release the parking brake while the vehicle
is raised.
R the jack must be placed on a firm, flat and
non-slip surface. On a loose surface, a
large, flat, load-bearing underlay must be
used. On a slippery surface, a non-slip
underlay must be used, e.g. a rubber mat.
R do not use wooden blocks or similar
objects as a jack underlay. Otherwise, the
jack will not be able to achieve its load-
bearing capacity due to the restricted
height.
R make sure that the distance between the
underside of the tyres and the ground does
not exceed 3 cm.
R never place your hands or feet under the
raised vehicle.
R do not lie under the vehicle.
R do not start the engine when the vehicle is
raised.
R do not open or close a door or the boot lid
when the vehicle is raised.
R make sure that no persons are present in
the vehicle when the vehicle is raised. Changing a wheel
607Wheels and tyres Z

Useful information
i This Owner's Manual describes all mod-
els, series and optional equipment for your
vehicle that were available at the time of
going to press. National variations are pos- sible. Note that your vehicle may not be
equipped with all of the functions descri-
bed. This is also the case for systems and
functions relevant to safety.
i Read the information on qualified special-
ist workshops: (Y page 34). Information on technical data
General notes
You can find current technical data on the
Internet on our Mercedes‑ Benz homepage.
i The technical data was determined in
accordance with EU Directives. All data
applies to the vehicle's standard equip-
ment. The data may therefore differ for
vehicles with optional equipment. You can
obtain further information from a
Mercedes-Benz Service Centre. Vehicle electronics
Tampering with the engine electron-
ics
! Only have work carried out on the engine
electronics and its associated parts, such
as control units, sensors and connector
leads, at a qualified specialist workshop.
Vehicle components may otherwise wear
more quickly and the vehicle's operating
permit may be invalidated. Retrofitting two-way radios and
mobile phones (RF transmitters)
G
WARNING
If RF transmitters are tampered with or not
properly retrofitted, the electromagnetic radi- ation they emit can interfere with the vehicle
electronics. This may jeopardise the opera-
tional safety of the vehicle. There is a risk of an
accident.
You should have all work on electrical and
electronic components carried out at a quali-
fied specialist workshop. G
WARNING
If you use the RF transmitter in the vehicle in
an improper way, its electromagnetic radia-
tion can disrupt vehicle electronics, e.g. if:
R the RF transmitter is not connected to an
exterior aerial
R the exterior aerial is fitted incorrectly or is
not a low-reflection aerial
This can jeopardise the operating safety of the vehicle. There is a risk of an accident.
Have the low-reflection exterior aerial fitted at
a qualified specialist workshop. When oper-
ating in the vehicle, always connect the RF
transmitter to the low-reflection exterior aer-
ial.
! The operating permit may be invalidated if
the instructions for installation and use of
RF transmitters are not observed.
In particular, the following conditions must be complied with:
R only approved wavebands may be used.
R observe the maximum permissible out-
put in these wavebands.
R only approved aerial positions may be
used.
Excessive levels of electromagnetic radiation
may cause damage to your health and to the
health of others. The use of an exterior aerial
takes into consideration the scientific discus- 620
Vehicle electronicsTechnical data