check engine light MERCEDES-BENZ SLK250 2012 R172 User Guide

Problems with the engine
Problem Possible causes/consequences and
0001 Solutions
The engine does not
start. The starter motor
can be heard. R
There is a malfunction in the engine electronics.
R There is a malfunction in the fuel supply.
X Before attempting to start the engine again, turn the SmartKey
in the ignition back to position 0or press the Start/Stop button
repeatedly until all indicator lamps in the instrumen tcluster go
out.
X Try to start the engine again (Y page 132). Avoid excessively
long and frequent attempts to start the engine as these will drain
the battery.
If the engine does not start after several attempts:
X Consult a qualified specialist workshop. The engine does not
start. You cannot hear
the starter motor. The on-board voltage is too low because the battery is too weak
or discharged.
X
Jump-star tthe vehicle (Y page 285).
If the engine does not start despite attempts to jump-start it:
X Consult a qualified specialist workshop. The starter motor was exposed to a thermal load that was too high.
X
Allow the starter motor to cool down for approximately two
minutes.
X Try to start the engine again.
If the engine still does not start:
X Consult a qualified specialist workshop. The engine is not
running smoothly and
is misfiring. There is a malfunction in the engine electronics or in a mechanical
component of the engine management system.
X
Only depress the accelerator pedal slightly.
Otherwise, non-combusted fuel may get into the catalytic
converter and damage it.
X Have the cause rectified immediately at a qualified specialist
workshop. The coolant
temperature gauge
shows a value above
248 ‡ (120 †). The coolant level is too low. The coolant is too hot and the engine
is no longer being cooled sufficiently.
X
Stop as soon as possible and allow the engine and the coolant
to cool down.
X Check the coolant level (Y page 262). Observe the warning
notes as you do so and add coolant if necessary. 138
DrivingDriving and parking

X
Completely insert the fille rneck of the fuel
pump nozzle into the tank and refuel.
X Only fill the tank until the pump nozzle
switches off.
i Do not add any more fuel after the pump
stops filling for the first time. Otherwise,
fuel may leak out.
Closing X
Replace the cap on the filler necka nd turn
clockwise until it engages audibly.
X Close fuel fille rflap 0002.
i If you drive with the fuel filler cap open,
reserve fuel warning lamp 0010flashes .In
addition, the 000ECheck Engine warning
lamp may light up. Amessage appears in
the multifunction display (Y page 219).
For further information on warning and
indicator lamps in the instrument cluster,
see (Y page 234). 148
RefuelingDriving and parking

Exhaust check
G
WARNING
Inhalation of exhaust gas is hazardous to your
health. All exhaust gas contains carbon
monoxide (CO), and inhaling it can cause
unconsciousness and possible death.
Do no trun the engin einconfined areas (such
as a garage) which are not properly ventilated.
If you think that exhaust gas fumes are
entering the vehicle while driving, have the
cause determined and corrected
immediately. If you must drive under these
conditions, drive only with at least one
window fully open at all times.
Certain engine systems are designed to keep
the level of poisonous components in exhaust
fumes within legal limits.
These systems only work at peak efficiency if
they are serviced exactly in accordance with
the manufacturer's specifications. For this
reason, all work on the engine should only be
carried out by qualified and authorized
Mercedes-Benz technicians.
The engine settings must not be changed
under any circumstances. Furthermore, all
specific service work must be carried out at
regular intervals and in accordance with the
Mercedes-Benz service requirements. Details
can be found in the Maintenance Booklet. Brakes
Important safety notes G
WARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
control. Your vehicle's ABS will not prevent
this type of loss of control. G
WARNING
Make sure that you do not endanger other
road users when you apply the brakes. Downhill gradients !
On long and steep gradients, you must
reduce the load on the brakes by shifting
early to a lower gear. This allows you to take
advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road
surface. This could cause damage to the
drive train. This type of damage is not
covered by the Mercedes-Benz warranty.
Heavy and light loads G
WARNING
Depressing the brake pedal constantly results
in excessive and premature wear to the brake
pads.
It may also cause the brakes to overheat,
seriously impairing their effectiveness. It may
then not be possible to stop the vehicle in
sufficient time to avoid an accident.
If the brakes have been subjected to a heavy
load, do not stop the vehicle immediately, but
drive on for a short while. This allows the
airflow to cool the brakes more quickly.
Wet roads G
WARNING
After driving in heavy rain for some time
without applying the brakes or through water
deep enough to wet brake components, the
first braking action may be somewhat
reduced. You have to depress the brake pedal
more firmly. Maintain a safe distance from
vehicles in front.
After driving on a wet road or having the
vehicle washed, brake firmly while paying
attention to the traffic conditions. This will
warm up the brake discs, thereby drying them
more quickly and protecting them against
corrosion. Driving tips
153Driving and parking Z

Limited braking performance on salt-
treated roads
G
WARNING
The layer of salt on th ebrake discs and the
brake pads/linings may caus eadelay in the
braking effect, resulting in a significantly
longer braking distance, which could lead to
an accident.
To avoid this danger, you should:
R occasionally brake carefully, without
putting other road users at risk, when you
are driving on salted roads. This helps to
remove any salt that may have started to
build up on the brake discs and the brake
pads/linings.
R maintain a greater distanc eto the vehicle
ahead and drive with particular care.
R carefully apply the brakes at the end of a
trip and immediately after commencing a
new trip, so that salt residues are removed
from the brake discs.
Servicing the brakes !
If the red brake warning lamp lights up in
the instrument cluster and you hear a
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at a qualified specialist workshop.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. Consult a
qualified specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop. G
WARNING
If brake pads or brake fluid other than those
recommended are used, the braking properties of the vehicle can be degraded to
an extentt
hat safe braking is substantially
impaired. This could result in an accident.
! As the ESP ®
system operates
automatically, the engine and the ignition
must be switched off (SmartKey in position
0 or 1in the ignition lock) if the electric
parking brake is being tested on a brake
dynamometer (maximum 10 seconds).
Braking triggered automatically by ESP ®
may seriously damage the brake system.
If the brake system has only been subject to
moderate loads, you should test the
functionality of your brakes at regular
intervals. To do so, press firmly on the brake
pedal when driving at a high speed. This
improves the grip of the brake pads. G
WARNING
Make sure that you do not endanger other
road users when you apply the brakes.
You can find a description of Brake Assist
(BAS) on (Y page 57).
High-performance brake system for
AMG vehicles The high-performance brake system is
installed only on the SLK 55 AMG.
G
WARNING
New vehicle brake pads and discs, and
replacement brake pads and discs may take
several hundred miles of driving until they
provide optimum braking efficiency. Until that
time, you may need to use increased brake
pedal pressure while braking. Please be aware
of this and adjust your driving and braking
accordingly during this break-in period.
Excessive high-demand braking will cause
correspondingly high brake wear. Please be
attentive to the brake warning lamp in the
instrument cluster and brake condition
messages in the multifunction display.
Especially for high performance driving, it is 154
Driving tipsDriving and parking

important to maintain and have the brake
system checked regularly.
The high-performance brake system is
designed for heavy loads. This may lead to
noise when braking. This will depend on:
R speed
R braking force
R environmental conditions, such as
temperature and humidity
The wear of individual components of the
brake system, such as the brake pads/linings
or brake discs, depends on the individual
driving style and operating conditions.
For this reason, it is impossible to state a
mileage that will be valid under all
circumstances. An aggressive driving style
will lead to high wear. You can obtain further
information about this fro myour authorized
Mercedes-Benz Center. Driving on wet roads
Hydroplaning If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if:
R you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or
in conditions in which hydroplaning can
occur, you must drive in the following
manner:
R lower your speed.
R avoid ruts.
R brake carefully.
Driving on flooded roads !
Do not drive through flooded areas.
Check the depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment. This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage.
Winter driving
Important safety notes G
WARNING
If the vehicle becomes trapped in snow,
ensure that snow is kept away from the
exhaust pipe and from around the vehicle as
long as the engine is running. Otherwise,
poisonous carbon monoxide (CO) may enter
the vehicle, resulting in loss of consciousness
and even death.
To assure sufficient fresh air ventilation, open
a window slightly on the side of the vehicle
not facing the wind.
Have your vehicle winterproofed at a qualified
specialist workshop at the onset of winter.
Observe the notes in the "Winter operation"
section (Y page 296).
Driving with summer tires Observe the notes in the "Winter operation"
section (Y
page 296).
Slippery road surfaces G
WARNING
The outside temperature indicator is not
designed to serve as an ice-warning device
and is therefore unsuitable for that purpose.
Indicated temperatures just above the
freezing point do not guarantee that the road
surface is free of ice. The road may still be icy,
especially in wooded areas or on bridges. G
WARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle Driving tips
155Driving and parking
Z

Display messages Possible causes/consequences and
0001 Solutions
The display message is only shown while the vehicle is in motion.
The yellow
000Awarning lamp lights up and the red 0005(USA
only)/ 000A(Canada only) indicato rlamp flashes.
It is no tpossible to apply the electric parking brake manually.
X Vehicles with manual transmission: engage first gear.
X Vehicles with automatic transmission: shift the transmission
to P.
X Visit a qualified specialist workshop. 0005(USA
only)000A(Canada
only)
Turn On the
Ignition to
Release the
Parking Brake The red
0005(USA only)/000A (Canada only) indicator lamp lights
up.
You attempted to release the electric parking brake while the
ignition was switched off.
X SmartKey: turn the SmartKey to position 1in the ignition lock.
X KEYLESS-GO: switch on the ignition. 000D(USA
only)0006(Canada
only)
Brake Immediately A malfunction has occurred while the HOLD function or
DISTRONIC PLUS is active.
At
one may also sound at regular intervals. If you attempt to lock
the vehicle, the tone becomes louder.
You cannot start the engine.
X Paying attention to the traffic situation, immediately depress the
brake pedal firmly and hold until the display message
disappears.
X Prevent the vehicle from rolling away before you leave it
(Y page 276).
You can restart the engine. 000D(USA
only)0006(Canada
only)
Check Brake Fluid
Level G
Risk of accident
There is not enough brake fluid in the brake fluid reservoir.
Additionally, the red 000D(USA only)/ 0006(Canada only)
warning lamp lights up in the instrument cluster and a warning
tone sounds.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Apply the electric parking brake.
X Consult a qualified specialist workshop.
X Do not add brake fluid. This does not correct the malfunction. 206
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
0001 Solutions
0001
Malfunction See
Operator's Manual The exterio
rlighting is defective.
X Visit a qualified specialist workshop. 0001
AUTO
Lamp Function
Inoperative The light sensor is defective.
X
Visit a qualified specialist workshop. 0001
Switch Off Lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X
Turn the light switch to 0008or0005. Engine
Displa
ymessages Possible causes/consequences and
0001 Solutions
000D
Check Coolant
Level See
Operator's Manual The coolant level is too low.
X
Add coolant, observing the warning notes when doing so
(Y page 262).
X If coolant needs to be added more often than usual, have the
engine coolant system checked at a qualified specialist
workshop. G
WARNING
Do not spill antifreeze on hot engine parts. Antifreeze contains ethylene glycol which may burn
if it comes into contac twith hot engine parts. You could be seriously burned.
! The coolan tlevel is too low. Avoid making long journeys with too little coolant in the cooling
system. The engine will otherwise be damaged.
The display messages and the corresponding symbol that indicate that the coolant level is
too low must not be ignored. 216
Display messagesOn-board computer and displays

G
WARNING
In the event a malfunction of the SRS is indicated as outlined above, the SRS may not be
operational.
For yours afety, we strongly recommend that you contac tanauthorized Mercedes-Ben zCenter
immediately to have the system checked. Otherwise the SRS may not be activated when needed
in an accident, which could result in serious or fatal injury, or it might deploy unexpectedly and
unnecessarily which could also result in injury. Engine
Problem Possible causes/consequences and
0001 Solutions
000E
The yellow Check
Engine warning lamp
lights up while the
engine is running. There may be a malfunction, for example:
R
in the engine management
R in the fuel injection system
R in the exhaust system
R in the ignition system
R in the fuel system
The emission limit values may be exceeded and the engine may
be running in emergency mode.
X Have the vehicle checked as soon as possible at a qualified
specialist workshop.
i In some states, you must immediately visit a qualified
specialist workshop as soon as the yellow Check Engine warning
lamp lights up. This is due to the legal requirement sineffect in
these states. If in doubt, check whether such legal regulations
apply in the state in which you are currently driving. 0010
The yellow reserve fuel
warning lamp flashes
while the vehicle is in
motion. In addition,
the
000E Check Engine
warning lamp may light
up. The fuel system pressure is too low
.The fuel filler cap is not closed
correctly or the fuel system is leaking.
X Observe the additional display messages in the multifunction
display.
X Check that the fuel filler cap is correctly closed.
X If the fuel filler cap is not correctly closed: close the fuel filler
cap.
X If the fuel filler cap is closed: visit a qualified specialist
workshop. 0010
The yellow reserve fuel
warning lamp lights up
while the engine is
running. The fuel level has dropped into the reserve range.
X
Refuel at the nearest gas station. 234
Warning and indicator lamps in the instrument clusterOn-board computer and displays

X
Reach into the gap, pull hoo dcatch
handle 0003up and lift the hood.
Once you have lifted the hood about
15 inches (40cm), it is automatically
opened the res tofthe way and held open
by the gas-filled struts.
Closing the hood G
WARNING
When closing the hood, use extreme caution
not to catch hands or fingers. Be careful that
you do not close the hood on anyone.
Make sure the hood is securely engaged
before driving off. Do not continue driving if
the hood can no longer engage after an
accident, for example. The hood could
otherwise come loose while the vehicle is in
motion and injure you and/or others.
X Lower the hood and let it fall from a height
of approximately 8inche s(20cm).
X Check that the hood has engaged properly.
If the hood can be raised slightly, it is not
properly engaged. Open it again and close
it with a little more force. Engine oil
Notes on the oil level Depending on the driving style, the vehicle
consumes up to 0.9 US qts
(0.8 l) of oil over
a distance of 600 miles (1,000 km). The oil
consumption may be highe rthan 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 261)
add oil if necessary (Y page 262). Race track
operation is only permitted with a maximum
engine oil level.
Depending on the engine, the oil dipstick may
be in 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
dipstick X
Pull oil dipstick 0002out of the dipstick guide
tube.
X Wipe off oil dipstick 0002.
X Slowly slide oil dipstick 0002into the guide
tube to the stop, and take it out again.
If the level is between MIN mark 0023and
MAX mark 0003, the oil level is correct.
X If the oil level is at or below MIN mark 0023,
add 0.55 US qt to 1.1 US qt (0.5 to 1.0 l) of
engine oil. Engine compartment
261Maintenance and care Z

Fuel
Important safety notes G
WARNING
Gasoline is highly flammable and poisonous.
It burns violently and can cause serious
personal injury.
Never allow sparks, flames or smoking
materials near gasoline.
Turn off the engine before refueling.
Wheneve ryou are around gasoline, avoid
inhaling fumes and any skin or clothing
contact.
Direct skin contact with fuels and the
inhalation of fuel vapors are damaging to your
health.
Tank capacity Total capacity
18.5 US gal (70.0 l)
Of which reserve
Approx. 2.4 US gal
(9.0 l) Gasoline
Fuel grade
!
Do not use diesel to refuel vehicles with a
gasoline engine. Even small amounts of the
wrong fuel result in damage to the fuel
system and engine.
! You should only refuel with unleaded
premium-grade gasoline as this avoids
damaging the catalytic converter.
If engine running problems are apparent,
have the cause checked immediately and
repaired. Excess unburned fuel can
otherwise enter the catalytic converter,
leading to overheating and possibly
causing a fire.
! To ensure the longevity and full
performance of the engine, only premium-
grade unleaded gasoline may be used. If there is no premium-grade unleaded
gasoline available and regular unleaded
gasoline must be used, please observe the
following precautions:
R
only fill the fuel tank to half full with
regular unleaded gasoline and fill the rest
with premium-grade unleaded gasoline
as soon as possible.
R do not drive at the maximum speed.
R avoid sudden acceleration.
R if the vehicle is carrying a light load, e.g.
two passengers without luggage, do not
allow the engine to rev above 3000 rpm.
R if the vehicle is fully loaded or is being
operated in mountainous terrain, do not
depress the accelerator pedal further
than 0001of the pedal travel.
Only refuel with premium-grade unleaded
gasoline with a minimum octane number of
91.
Reformulated Gasoline (RFG) and/or
unleaded gasoline with additives can be used.
However, the concentration of additives in
the fuel must be less than 10%, e.g.
R Ethanol
R TAME
R ETBE
R IPA
R TBA
For MTBE, the concentration should not
exceed 15%.
The concentration of methanol in gasoline
including other additives must not exceed
3%.
Using mixtures of methanol and ethanol is not
permitted. Gasohol, a mixture of 10% ethanol
and 90% unleaded gasoline, can be used.
All of these mix fuels must fulfill the fuel
requirements, e.g.:
R knock resistance
R boiling point
R vapor pressure Service products and filling capacities
325Technical data Z