2012 MERCEDES-BENZ SLK ROADSTER check engine

Problem Possible causes/consequences and
M Solutions
M
AMG vehicles only:
The yellow SPORT han-
dling mode warning
lamp is lit while the
engine is running.
G
Risk of accident
SPORT handling mode is activated. ESP ®
only stabilises the vehi-
cle in extreme situations. ESP ®
intervention may not be able to
provide sufficient assistance in such situations, and the vehicle
may start to skid.
X Reactivate ESP ®
.
For exceptions, see: (Y page 56).
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. G
Risk of accident
ESP ®
, BAS, BAS PLUS, PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD
function, hill start assist and the adaptive brake lights are not
available due to a malfunction .ESP ®
will not stabilise the vehicle
if it starts to skid or if a wheel starts to spin.
The brake system continues to function normally, bu twithout the
functions listed above.
ATTENTION ASSIST is deactivated.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
229On-board computer and displays Z

Engine
Problem Possible causes/consequences and
M Solutions
;
The yellow engine diag-
nostics warning lamp
lights up while the
engine is running.
There may be a fault, for example:
R in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system (for vehicles with petrol engines)
R in the fuel system
The emission limit values may be exceeded and the engin emay
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop. Vehicles with a diesel engine: the fuel tan
khas been run dry
(Y page 145).
X Start the engine three to four times after refuelling.
If the yellow engine diagnostics warning lamp goes out, emer-
gency running mode is cancelled. The vehicle need no tbe
checked. 8
The yellow reserve fuel
warning lamp lights up
while the engine is run-
ning.
The fuel level has dropped into the reserve range.
X
Refuel at the nearest filling station. ?
The red coolant warn-
ing lamp lights up while
the engine is running
and the coolant tem-
perature gauge is at the
star toft he scale. The temperature sensor for the coolant temperature gauge is
faulty.
The coolant temperature is no longer being monitored. There is a
risk of engine damage if the coolant temperature is too high.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine. Do not continue driving
under any circumstances.
X Engage the electric parking brake.
X Consult a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
231On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning.
The coolant level is too low.
If the coolant level is correct, the airflow to the engine radiator
may be blocked or the electric engine radiator fan may be mal-
functioning.
The coolant is too hot and the engine is no longer being cooled
sufficiently.
X
Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 251).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. ?
The red coolant warn-
ing lamp comes on
while the engine is run-
ning. A warning tone
also sounds.
The coolant temperature has exceeded 120 †. The airflow to the
engine radiator may be blocked or the coolant level may be too
low.
The engine is not being cooled sufficiently and may be damaged.
X Observe the additional display messages in the multifunction
display.
X Stop the vehicle immediately, paying attention to road and traf-
fic conditions, and switch off the engine.
X Let the engine and coolant cool down.
X Check the coolant level and top up the coolant (Y page 251).
Observe the warning notes as you do so.
X If you have to top up the coolant frequently, have the engine
cooling system checked.
X Make sure that the air supply to the engine radiator is not
blocked, e.g. by frozen slush.
X If the coolant temperature is less than 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid heavy loads on the engine as you do so, e.g. driving on
mountain roads and stop-start traffic. 232
Warning and indicator lamps in the instrument clusterOn-board computer and displays

X
Lower the bonnet and let it fall from a
heightofa pproximately 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. Radiator
i Vehicles with adiesel engine: do not
cover the radiator. Do not use thermal
mats, insect protection covers or anything
similar. Doing so can cause the Onboard
Diagnostics System to display inaccurate
values. Some of these values are legally
required and must be correct. Engine oil
Notes on oil level Depending on driving style, the vehicle con-
sumes up to 0.
8lof 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.
AMG vehicles: before operation on race
tracks, check the oil level and (Y page 250)
top up if necessary (Y page 250). Race track
operation is only permitted with a maximum
engine oil level.
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 about 30 minutes
before carrying out the measurement. Checking the oil level using the oil dip-
stick
Example: vehicles with a petrol engine
Example: vehicles with a diesel engine
X
Pull oil dipstick :out of the oil 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, add 0.5to 1.0litre of engine
oil.
Adding engine oil G
WARNING
If engine oil comes into contact with hot
engine parts, it may ignite and you could burn
yourself. Do not spill any engine oil on hot
engine parts. 250
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
service 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. Topping up with
too much engine oil can result in damage
to the engine or to the catalytic converter.
Have excess engine oil siphoned off. Example: engine oil cap
X
Turn cap :anti-clockwise and remove it.
X Top up the engine oil.
If the oil level is at or under the MIN mark
on the oil dipstick, add 0.5 to 1.0 litre of
engine oil. X
Replace cap :on the filler neck and turn
clockwise.
Make sure that the cap locks into place
securely.
X Chec kthe oil level again with the oil dip-
stick (Y page 250).
Further information on engine oil
(Y page 307). Checking and adding other service
products
Checking the coolant level G
WARNING
The cooling system is pressurised. Therefore,
only unscrew the cap once the engine has
cooled down. The coolant temperature gauge
must display less than 70 †.Otherwise, you
could be scalded if hot coolant escapes. 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 127).
On vehicles with KEYLESS-GO, press the
Start/Stop button twice (Y page 127).
X Check the coolant temperature display in
the instrument cluster.
The coolant temperature must be below
70 †.
X Turn the key to position 0(Ypage 127) in
the ignition lock. Engine compartment
251Maintenance and care Z

G
WARNING
For safety reasons, Mercedes-Benz recom-
mends that you only use batteries which have
been tested and approved for yourv ehicle by
Mercedes-Benz .These batteries provide
increased impact protection to prevent vehi-
cle occupants from suffering acid burns
should the battery be damaged in the event
of an accident.
To prevent acid burns, observe the following
safety notes when handling batteries:
R do not lean over the battery.
R do not place any metal objects on a battery.
Otherwise, you could cause a short circuit
and the battery's gas mixture could ignite.
R make sure that you do not create an elec-
trostatic charge, e.g. by wearing synthetic
clothing or as a result of friction on fabrics.
Therefore, you should not pull or slide the
battery over carpets or other synthetic
materials.
R never touch the battery first. To discharge
a possible electrostatic charge, step out of
the vehicle first and touch the bodywork.
R do not wipe the battery using a cloth. The
battery may explode as a result of electro-
static charge or due to flying sparks.
! Switch off the engine and remove the key
before disconnecting the terminal clamps
from the battery. On vehicles with KEY-
LESS-GO, make sure that the ignition is
switched off. Check that all the indicator
lamps in the instrumentc luster are off.You
may otherwise destroy electronic compo-
nents, such as the alternator.
i When you park the vehicle, remove the
key if you do not require any electrical con-
sumers. The vehicle will then use very little
energy, thus conserving battery power.
Mercedes-Benz recommends that you do not
carry out work on batteries yourself, e.g.
removing or charging. Have this work per-
formed at a qualified specialist workshop. Installation location of the battery
Your vehicle is equipped with a battery in the
engine compartment.Iti s located on the front
bulkhead under the water tank on the right-
hand side of the vehicle when viewed in the
direction of travel.
X Apply the electric parking brake and shift
the transmission to position P.
X Switch off all electrical consumers (e.g.
radio, blower, etc.).
X Turn the key to position 0(Ypage 127) in
the ignition lock and remove it, or, on vehi-
cles with KEYLESS-GO, make sure that the
ignition has been switched off
(Y page 127). All indicator lamps in the
instrument cluster must be off.
X Open the bonnet (Y page 248). X
Turn fasteners ;a quarter of a turn.
X Remove water tank :.
The battery is located under water
tank :. Disconnecting the battery
! Always disconnect the battery in
the order described below. Never swap the
terminal clamps. You may otherwise dam-
age the vehicle electronics.
In vehicles with automatic transmission,
the transmission is locked in position P
after disconnecting the battery. The vehicle
is secured against rolling away. You can
then no longer move the vehicle. 274
BatteryBreakdown assistance

Position number
Bidentifies the charged battery of the other vehicle or an equivalent jump-
starting device.
X Slide cover :of positive terminal ;in the direction of the arrow.
X Connec tpositive terminal ;on your vehicle to positive terminal =of donor battery B
using the jump lead, beginning with your own battery.
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, connectingt he jump lead to donor battery Bfirst.
X Start the engine.
X Before disconnecting the jump leads, let the engine run for several minutes.
X First remove the jump leads from earth point Aand negative terminal ?, then from positive
terminal ;and positive terminal =, each time beginning at the contacts on your own
vehicle first.
X Close cover :of positive terminal ;after removing the jump leads.
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
Observe the legal requirements for the rele-
vant countries when towing and tow-starting. G
WARNING
If you tow the vehicle, you must use a rigid
towing bar if:
R the engine is not running.
R there is a brake system malfunction.
R there is a malfunction in the power supply
or the vehicle's electrical system. 278
Towing and tow-startingBreakdown assistance

loaded and result in a fire. Have the cause
traced and rectified at a qualified specialist
workshop.
The fuses in your vehicle serve to close down
faulty circuits. If afuse blows, all the compo-
nents on the circuit and their functions stop
operating.
Blown fuses must be replace dwith 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
Service Centre.
! Only use fuses that have been approved
for Mercedes-Ben zvehicles and which
have the correct fuse rating for the system
concerned. Otherwise, components or sys-
tems could be damaged. Before replacing a fuse
X Park the vehicle and apply the electric park-
ing brake.
X Switch off all electrical consumers.
X Remove the key from the ignition lock.
The fuses are located in various fuse boxes:
R fuse box in the engine compartment on the
left-hand side of the vehicle, when viewed
in the direction of travel
R fuse box in the boot behind the partition
trim
The fuse allocation chart is located in the
vehicle tool kit (Y page 261) in the stowage
compartment under the boot floor. Fuse box in the engine compartment
X Make sure that the windscreen wipers are
turned off. G
WARNING
Make sure that the windscreen wipers are
turned off and the key is pulled out of the igni-
tion lock before you open the cover of the fuse
box. Otherwise, the windscreen wipers and
the wiper rods above the cover could be set
in motion .This could lead to you or others
being injured by the wiper rods.
X Open the bonnet (Y page 248). X
Remove any existing moisture from the
fuse box using a dry cloth.
X To open: open clamps :.
X Remove fuse box cover ;forwards.
! Make sure that no moisture can enter the
fuse box when the cover is open.
X To close: check whether the rubber seal is
lying correctly in cover ;.
X Insert cover ;at the rear of the fuse box
into the retainer.
X Fold down cover ;and close clamps :.
! The cover must be fitted properly, other-
wise moisture or dirt could impair the func-
tion of the fuses.
X Close the bonnet (Y page 249). Fuse box in the boot
The fuse box is located in the boot behind the
partition covering.
X Open the boot lid (Y page 73).282
Electrical fusesBreakdown assistance