engine MERCEDES-BENZ SL ROADSTER 2012 Owners Manual

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). Engine compartment
Bonnet
Important safety notes G
WARNING
An unlocked bonnet may open while driving
and block your view. There is a risk of an acci- dent.
Never unlock the bonnet while driving. G
WARNING
When being opened and closed, the bonnet
may suddenly fall into the closed position.
There is a risk of injury to persons in the range of movement of the bonnet.
Open and close the bonnet only when nobody
is in the range of movement. G
WARNING
If you open the bonnet while the engine is
overheating or while there is a fire in the
engine compartment, you could come into
contact with hot gases or other leaking ser-
vice products. There is a danger of injury.
Allow an overheating engine to cool down
before opening the bonnet. If there is a fire in the engine compartment, leave the bonnet
closed and notify the fire brigade. G
WARNING
There are moving components in the engine
compartment. Certain components may con-
tinue to move or suddenly move again even
after the ignition has been switched off, e.g.
the radiator fan. There is a risk of injury.
If you have to carry out work in the engine
compartment:
R switch off the ignition
R never touch the dangerous areas surround-
ing moving components, e.g. the rotation
area of the fan
R remove jewellery and watches
R keep items of clothing and hair, for exam-
ple, away from moving parts.
Active bonnet (pedestrian protection) Operating principle
! An active bonnet that had been triggered
must be repaired at a qualified specialist
workshop. The active bonnet function will
then be available again. The additional
pedestrian protection provided by the
active bonnet will then be restored.
The active bonnet is only available in certain
countries.
The active bonnet can reduce the risk of injury to pedestrians in certain accident situations.
Raising the active bonnet increases the clear-
ance to hard components, such as the engine.
If the active bonnet has been triggered, it is
raised at the rear in the area around the hinge
by approximately 85 mm. The active bonnet is triggered by pyrotechnics.
For the drive to the workshop, reset the trig-
gered active bonnet yourself. If the active
bonnet has been triggered, pedestrian pro-
tection may be limited.
Resetting G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system. 562
Engine compartmentMaintenance and care

There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents. X
With your hand flat, push down active bon-
net :in the area around the hinges on
both sides (arrows) until you feel it engage.
If you can raise the active bonnet slightly in
the area around the hinges, it is not engaged correctly. Repeat the step.
Opening the bonnet G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents. 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 the windscreen wipers are
not folded away from the windscreen. Oth-
erwise, you could damage the windscreen
wipers or the bonnet. X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap, pull bonnet catch han-
dle ;up and lift the bonnet.
If you lift the bonnet by approximately
40 cm, the bonnet is opened and held open automatically by the gas-filled strut.
Closing the bonnet X
Lower the bonnet and let it fall from a
height of approximately 20 cm.
X Check that the bonnet has engaged prop-
erly.
If the bonnet can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Engine compartment
563Maintenance and care Z

Engine oil
Notes on oil level Depending on your driving style, the vehicle
consumes up to 0.8 litres of oil per 1,000 km.
The oil consumption may be higher than this
when the vehicle is new or if you frequently
drive at high engine speeds.
Depending on the engine, the oil dipstick may be installed at a different location.
When checking the oil level:
R park the vehicle on a level surface.
R the engine should be switched off for
approximately five minutes if the engine is
at normal operating temperature.
R if the engine is not at normal operating
temperature, e.g. if the engine was only
started briefly, wait approximately
30 minutes before carrying out the meas-
urement.
Checking the oil level using the oil dip-
stick G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents. Example
X Pull oil dipstick :out of the dipstick tube.
X Wipe off oil dipstick :.
X Slowly slide oil dipstick :into the guide
tube to the stop, and take it out again.
If the level is between MIN mark =and
MAX mark ;, the oil level is correct.
X If the oil level has dropped to MIN mark =
or below, top up with 1.0 l of engine oil.
Adding engine oil G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents. G
WARNING
If engine oil comes into contact with hot com- ponents in the engine compartment, it may
ignite. There is a risk of fire and injury.
Make sure that engine oil does not spill out
over the filler neck. Allow the engine to cool
down and thoroughly clean the components
that have come into contact with engine oil
before you start the engine. 564
Engine compartmentMaintenance and care

H
Environmental note
When topping up the oil, take care not to spill any. If oil enters the soil or waterways, it is
harmful to the environment.
! Only use engine oils and oil filters that
have been approved for vehicles with a ser-
vice system. You can obtain a list of the
engine oils and oil filters tested and
approved in accordance with the
Mercedes-Benz Specifications for Service
Products at any Mercedes-Benz Service
Centre.
Damage to the engine or exhaust system is caused by the following:
R using engine oils and oil filters that have
not been specifically approved for the
service system
R changing the engine oil and oil filter after
missing the change interval required by
the service system
R using engine oil additives
! Do not add too much oil. If the oil level is
above the "max" mark on the dipstick, too
much oil has been added. This can lead to
damage to the engine or the catalytic con-
verter. Have excess oil siphoned off. Example: engine oil filler cap
X Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or below the MIN mark on
the oil dipstick, top up with 1.0 l of engine
oil. X
Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks securely into place.
X Check the oil level again with the oil dip-
stick (Y page 564).
For further information on engine oil, see
(Y page 626). Checking and adding other service
products
Checking the coolant level G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents. G
WARNING
The engine cooling system is under pressure, particularly if the engine is warm. You could
be scalded by hot coolant spraying out when
opening the cap. There is a danger of injury.
Allow the engine to cool before opening the
cap. Wear gloves and protective eyewear
when opening. Slowly turn the cap half a turn
to allow pressure to escape. Example Engine compartment
565Maintenance and care Z

X
Park the vehicle on a level surface.
Only check the coolant level if the vehicle is
on a level surface and the engine has
cooled down.
X Turn the key to position 2in the ignition
lock (Y page 155).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 155).
X Check the coolant temperature gauge in
the multifunction display.
The coolant temperature must be below
70 †.
X Turn the key to position 0(Y page 155) in
the ignition lock.
X Slowly turn cap ;half a turn anti-clock-
wise to allow excess pressure to escape.
X Turn cap ;further anti-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank :.
If the coolant level is approximately 1.5 cm above marker bar =in the filler neck when
warm, there is enough coolant in coolant
expansion tank :.
X If necessary, top up with coolant that has
been tested and approved by Mercedes-
Benz.
X Replace cap ;and turn it clockwise as far
as it will go.
For further information on coolant, see
(Y page 627).
Windscreen washer system and head-
lamp cleaning system G
WARNING
Certain components in the engine compart-
ment could be very hot, e.g. the engine, the
radiator and parts of the exhaust system.
There is a risk of injury when accessing the
engine compartment.
As far as possible, allow the engine to cool
down and only touch the following compo-
nents. G
WARNING
Windscreen washer concentrate is highly
flammable. If it comes into contact with hot
engine components or the exhaust system it
could ignite. There is a risk of fire and injury.
Make sure that no windscreen washer con-
centrate is spilled next to the filler neck. Example
X To open: pull cap:upwards by the tab.
X Top up with the premixed washer fluid.
X To close: press cap :onto the filler neck
until it engages.
The washer fluid reservoir is used for both the
windscreen washer system and the headlamp cleaning system.
If the washer fluid level drops below the rec-
ommended minimum of 1 litre, a message
appears in the multifunction display prompt-
ing you to top up the washer fluid
(Y page 272).
Further information on windscreen washer
fluid/antifreeze (Y page 628). ASSYST PLUS
Service messages
The ASSYST PLUS service interval display
informs you of the next service due date.
Information on the type of service and service
intervals (see separate Service Booklet).
You can obtain further information from a
Mercedes-Benz Service Centre. 566
ASSYST PLUSMaintenance and care

i
The ASSYST PLUS service interval display
does not show any information on the
engine oil level. Observe the notes on the
engine oil level (Y page 564).
The multifunction display shows a service
message for a few seconds, e.g.:
R Service A in .. days
Service A in .. days
R Service A due Service A due
R Service A overdue by .. days
Service A overdue by .. days
Depending on the operating conditions of the vehicle, the remaining time or distance until
the next service due date is displayed.
The letter indicates which service is due. A A
stands for a minor service and B
Bfor a major
service. A number or another letter may be
displayed after the letter.
Only for certain countries: the position after
the letter A
A or B Bindicates any necessary addi-
tional maintenance work to be performed. If
you notify a qualified specialist workshop of
this display, you will receive a statement on
the associated costs.
The ASSYST PLUS service interval display
does not take into account any periods of
time during which the battery is disconnec-
ted.
Maintaining the time-dependent service
schedule:
X Note down the service due date displayed
in the multifunction display before discon-
necting the battery.
or X After reconnecting the battery, subtract
the battery disconnection periods from the service date shown on the display. Hiding a service message
X Press the aor% button on the steer-
ing wheel. Displaying a service message
X Switch the ignition on.
X Press the =or; button on the steer-
ing wheel to select the Serv. Serv.menu.
X Press the 9or: button to select the
ASSYST PLUS ASSYST PLUS submenu and confirm by
pressing the abutton.
The service due date appears in the multi-
function display. Information about Service
Resetting the ASSYST PLUS service
interval display !
If the ASSYST PLUS service interval dis-
play has been inadvertently reset, this set-
ting can be corrected at a qualified special-
ist workshop.
Have service work carried out as described in the Service Booklet. This may otherwise
lead to increased wear and damage to the
major assemblies or the vehicle.
A qualified specialist workshop, e.g. a
Mercedes-Benz Service Centre, will reset the ASSYST PLUS service interval display after
the service work has been carried out. You
can also obtain further information on main-
tenance work, for example.
Special service requirements The prescribed service interval is based on
normal operation of the vehicle. Service work
will need to be performed more often if the
vehicle is operated under arduous conditions
or increased loads, for example:
R regular city driving with frequent intermedi-
ate stops
R if the vehicle is primarily used to travel
short distances
R for frequent operation in mountainous ter-
rain or on poor road surfaces
R if the engine is often left idling for long peri-
ods ASSYST PLUS
567Maintenance and care Z

In these or similar operating conditions, have
the air filter, engine oil and oil filter, for exam- ple, changed more frequently. The tyres mustbe checked more frequently if the vehicle is
operated under increased loads. Further
information can be obtained at a qualified
specialist workshop, e.g. a Mercedes-Benz
Service Centre.
Driving abroad An extensive Mercedes-Benz Service network
is also available in other countries. You can
obtain further information from any
Mercedes-Benz Service Centre. Care
Notes on care
H
Environmental note
Dispose of empty packaging and cleaning
cloths in an environmentally responsible man- ner.
! For cleaning your vehicle, do not use any
of the following:
R dry, rough or hard cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvents
Do not scrub.
Do not touch the surfaces or protective
films with hard objects, e.g. a ring or ice
scraper. You could otherwise scratch or
damage the surfaces and protective film.
! Do not park up the vehicle for an extended
period straight after cleaning it, particularly after having cleaned the wheels with wheel
cleaner. Wheel cleaners could cause
increased corrosion of the brake discs and
brake pads/linings. For this reason, you
should drive for a few minutes after clean-
ing. Braking heats the brake discs and the
brake pads/linings, thus drying them. The
vehicle can then be parked up. Regular care of your vehicle is a condition for
retaining the quality in the long term.
Use care products and cleaning agents rec-
ommended and approved by Mercedes-Benz. Washing the vehicle and cleaning the
paintwork
Automatic car wash G
WARNING
Braking efficiency is reduced after the vehicle has been washed. There is a risk of an acci-
dent.
After washing the vehicle, brake carefully
while paying attention to the traffic conditions in order to restore full braking efficiency.
! 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
! It is preferable to use car washes with
adjustable high-pressure pre-cleaning that
corresponds to the specification for the
Cabriolet programme. In car washes that
use high water pressures, there is a risk
that a small amount of water may leak into
the vehicle.
! Vehicles with HANDS-FREE ACCESS: if a
key with KEYLESS-GO is within the detec-
tion range of the KEYLESS-GO antenna, the
following situations could lead to the unin-
tentional opening of the boot lid:
R using a car wash
R using a high-pressure cleaner
Make sure that the key is at least 2 maway
from the vehicle.
! Make sure that the automatic transmis-
sion is in position Nwhen washing your 568
CareMaintenance and care

Tyre-change tool kit
:
Bag containing the tyre-changing tools
X Open the boot lid.
X Open the boot separator (Y page 106).
X Lift the boot floor upwards (Y page 548).
i Depending on the vehicle equipment, not
all vehicles will have the tools that are
required for changing a wheel, such as a
jack. Tools approved for your vehicle are
available at a qualified specialist workshop.
Bag with tyre-changing tools :contains:
R jack
R wheel wrench
R centring pin
R wheel chock
R gloves Flat tyre
Preparing the vehicle
Your vehicle may be equipped with: R MOExtended tyres (tyres with run-flat char-
acteristics) (Y page 578)
Vehicle preparation is not necessary on
vehicles with MOExtended tyres.
R a TIREFIT kit (Y page 579)
R an emergency spare wheel (only for certain
countries) (Y page 614)
Information on changing/fitting a wheel
(Y page 605). X
Stop the vehicle on solid, non-slippery and
level ground, as far away from traffic as
possible.
X Switch on the hazard warning lamps.
X Secure the vehicle against rolling away
(Y page 175).
X If possible, bring the front wheels into the
straight-ahead position.
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 All occupants must get out of the vehicle.
Make sure that they are not endangered as
they do so.
X Make sure that no one is near the danger
area while a wheel is being changed. Any-
one who is not directly assisting in the
wheel change should, for example, stand
behind the barrier.
X Get out of the vehicle. Pay attention to traf-
fic conditions when doing so.
X Close the driver's door.
X Place the warning triangle a suitable dis-
tance away (Y page 576). Observe legal
requirements. MOExtended tyres (tyres with run-flat
characteristics)
General notes With MOExtended tyres (tyres with run-flat
characteristics), you can continue to drive
your vehicle even if there is a total loss of
pressure in one or more tyres. The affected
tyre must not show any clearly visible dam-
age. 578
Flat tyreBreakdown assistance

G
WARNING
Work carried out incorrectly on the battery
may lead to a malfunction, e.g. a short circuit. This, in turn, may restrict the functions of the
safety-relevant systems, e.g. the lighting sys-
tem, ABS (Anti-lock Braking System) or ESP ®
(Electronic Stability Program). The operating
safety of your vehicle may then be compro-
mised. You could then lose control of the vehi-
cle, e.g.:
R when braking
R when making sudden steering movements
and/or travelling at an inappropriate
speed.
There is a risk of an accident.
In the event of a short circuit or similar situa-
tion, inform a qualified specialist workshop
immediately. Do not drive any further. You
should have all work involving the battery car- ried out at a qualified specialist workshop.
Further information on ABS and ESP ®
(Y page 71) and (Y page 73). G
WARNING
Electrostatic build-up can lead to the creation of sparks, which could ignite the highly explo-
sive gases of a battery. There is a risk of an
explosion.
Before handling the battery, touch the vehicle body to remove any existing electrostatic
build-up.
The highly flammable gas mixture is created
while the battery is charging and when jump-
starting.
Always make sure that neither you nor the
battery is electrostatically charged. Electro-
static charge is created, for example:
R by wearing synthetic fibre clothing
R due to friction between clothing and the
seat
R when you pull or push the battery across
carpet or other synthetic materials
R when you rub the battery with a cloth G
WARNING
During the charging process, a battery produ- ces 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 con-
tact with vehicle parts.
R Never place metal objects or tools on a bat-
tery.
R It is important that you observe the descri-
bed 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 dis-
connecting the jump leads.
R Never connect or disconnect the battery
terminals while the engine is running. 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. H
Environmental note Batteries contain pollutants.
It is illegal to dispose of them
with the household rubbish.
They must be collected sep-
arately and disposed of in anenvironmentally responsible
recycling system. Dispose of batteries in an
environmentally responsible
manner. Take discharged
batteries to a qualified spe-
cialist workshop or to a col-
lection point for used batter-
ies. Battery (vehicle)
583Breakdown assistance Z

!
Have the battery checked regularly at a
qualified specialist workshop.
Observe the service intervals in the Service
Booklet or contact a qualified specialist
workshop for more information.
! You should have all work involving the
battery carried out at a qualified specialist
workshop. In the exceptional case that it is
necessary for you to disconnect the battery yourself, make sure that:
R you switch off the engine and remove the
key. On vehicles with KEYLESS-GO,
ensure that the ignition is switched off.
Check that all the indicator lamps in the
instrument cluster are off. Otherwise,
electronic components, such as the
alternator, may be damaged.
R you first remove the negative terminal
clamp and then the positive terminal
clamp. Never swap the terminal clamps.
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be fitted securely dur- ing operation.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Comply with safety precautions and take pro-
tective measures when handling batteries. WARNING
Fire, naked flames and smoking
are prohibited when handling the
battery. Avoid creating sparks.
Battery acid is caustic. Avoid con-
tact with the skin, eyes or clothing. Wear suitable protective clothing,
in particular gloves, an apron and a
face mask.
Immediately rinse acid splashes
off with clean water. Consult a doc- tor if necessary. Wear eye protection.
Keep children away.
Observe this Owner's Manual.
The vehicle battery, like other batteries, can
discharge over time if you do not use the
vehicle. In such cases, have the battery dis-
connected at a qualified specialist workshop.
You can also charge the battery with a
charger recommended by Mercedes-Benz.
For more information, please contact a quali- fied specialist workshop.
Have the battery charge checked more fre-
quently if you use the vehicle mainly for short
trips or if you leave it standing idle for a
lengthy period. Consult a qualified specialist
workshop if you wish to leave your vehicle
parked up for a long period of time.
i When you park the vehicle, remove the
key if you do not require any electrical con- sumers. The vehicle will then use very littleenergy, thus conserving battery power. Charging the battery
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 584
Battery (vehicle)Breakdown assistance