2012 MERCEDES-BENZ SLK250 check engine

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops (Y page 23).Occupant safety
Overview of occupant safety
In this section, you will learn the most
important facts about the restraint system
components of the vehicle.
The restraint system consists of:
R seat belts
R child restraint systems
Additional protection is provided by:
R SRS (Supplemental Restrain tSystem)
R NECK-PRO head restraints
R Airb ag system component swith:
- PASSENGER AIR BAG ON/OFF indicator
lamp 2
- front-passenger seat with Occupant
Classification System (OCS)
The differen tair bag systems work
independently of each other. The protective
functions of the system work in conjunction
with each other. Not all air bags are deployed
in an accident. G
WARNING
Modifications to or work improperly
conducted on restraint system components
or their wiring, as well as tampering with
interconnected electronic systems, can lead to the restraint systems no longer functioning
as intended.
Air bags or Emergency Tensioning Devices
(ETDs), for example, could deploy
inadvertently or fail to deploy in accidents
although the deceleration threshold for air
bag deploymen tis exceeded. Therefore,
never modify the restraint systems. Do not
tamper with electronic components or their
software.
i See "Children in the vehicle"
(Y page 53) for more information on
infants and children traveling with you in
the vehicle and restraints for infants and
children. SRS (Supplemental Restraint System)
Introduction SRS consists of:
R
the 0019 SRS warning lamp
R air bags
R air bag control unit (with crash sensors)
R Emergency Tensioning Devices
R belt force limiters
SRS reduces the risk of occupants coming
into contact with the vehicle's interior in the
event of an accident. It can also reduce the
effect of the forces to which occupants are
subjected during an accident.
SRS warning lamp SRS functions are checked regularly when
you switch on the ignition and when the
engine is running. Therefore, malfunctions
can be detected in good time.
The
0019 SRS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out no later than a few seconds
after the engine is started.
2 The PASSENGER AIR BAG ON indicator lamp has no function. When switching on the ignition, it lights up
briefly and then goes out again. 36
Occupant safetySafety

The SRS components are in operational
readiness if the
0019SRS warning lamp is not
lit while the engine is running. G
WARNING
The SRS self-check has detected a
malfunction if the 0019SRS indicator lamp:
R does not light up at all
R does not go out after approximately four
seconds after the engine is started
R comes on after the engine was started or
while driving.
For your safety, Mercedes-Benz strongly
recommends that you have the system
checked as soon as possible at an authorized
Mercedes-Benz Center. SRS may otherwise
fail to activate when it is needed in the event
of an accident, which could lead to serious or
fatal injuries. SRS might also be activated
unexpectedly and unnecessarily, which could
also result in injury.
In addition, work carried out improperly on
SRS may render SRS inoperative or cause
unintended air bag deployment. Work on the
SRS system should only be carried out by
qualified specialist personnel. Consult an
authorized Mercedes-Benz Center.
If it is necessary to modify an air bag system
to accommodate a person with disabilities,
contact an authorized Mercedes-Benz Center
for details. USA only: for further information
contact our Customer Assistance center at
1-800-FOR-MERCedes (1-800-367-6372).
Safety guidelines for seat belts,
Emergency Tensioning Devices (ETDs)
and air bags G
WARNING
R Damaged seat belts or seat belts that have
been subjected to stress in an accident
must be replaced. Their anchoring points
must also be checked. Only use seat belts installed or supplied by an authorized
Mercedes-Benz Center.
R Air bags and pyrotechnic Emergency
Tensioning Devices (ETDs) contain
perchlorate material, which may require
special handling and regard for the
environment.C heck your national disposal
guidelines. California residents, see
www.dtsc.ca.gov/HazardousWaste/
Perchlorate/index.cfm.
R Air bags and ETDs are designed to function
on a one-time-only basis. An air bag or ETD
that has deployed must be replaced.
R Do not pass seat belts over sharp edges.
They could tear.
R Do not make any modification that could
change the effectiveness of the seat belts.
R Do not bleach or dye seat belts as this may
severely weaken them. In a crash they may
not be able to provide adequate protection.
R No modifications of any kind may be made
to any components or wiring of the SRS.
R Do not change or remove any component
or part of the SRS.
R Do not install additional trim material, seat
covers, badges, etc. over the steering
wheel hub, front-passenger front air bag
cover, outer sides of the seat backrests,
door trim panels, or door frame trims.
R Do not install additional electrical/
electronic equipment on or near SRS
components and wiring.
R Keep area between air bags and occupants
free of objects (e.g. packages, purses,
umbrellas, etc.).
R Air bag system components will be hot after
an air bag has inflated. Do not touch them.
R Never place your feet on the instrument
panel, dashboard, or on the seat. Always
keep both feet on the floor in front of the
seat.
R Improper repair work on the SRS creates a
risk of rendering the SRS inoperative or
causing unintended air bag deployment.
Work on the SRS must therefore only be Occupant safety
37Safety
Z

automatically increase the braking force to a
level suitable for the traffic conditions.
If BAS PLUS demands particularly high
braking force, preventative passenger
protection measures (PRE-SAFE ®
) are
activated simultaneously.
X Keep the brake pedal depressed until the
emergency braking situatio nis over.
ABS prevents the wheels from locking.
The brakes will work normally againi f:
R you release the brake pedal.
R there is no longe rany dange rofarear-end
collision.
R no obstacle is detected in front of your
vehicle.
BAS PLUS is then deactivated.
For BAS PLUS to assist you when driving, the
rada rsensor system must be switched on and
operational; see "Rada rsensor system" in the
index. G
WARNING
BAS PLUS cannot always clearly identify
objects and complex traffic situations. BAS
PLUS cannot intervene in these cases.
There is a risk of an accident. Always pay
careful attention to the traffic situation and be
ready to brake.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other radar sources
R the possibility of strong radar reflections,
for example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in fron tonadifferent line G
WARNING
BAS PLUS does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R in curves
As a result, BAS PLUS cannot intervene in
critical situations. There is a risk of an
accident. Always pay careful attention to the
traffic situation and be ready to brake.
Following damage to the fron tend of the
vehicle, have the configuratio nand operation
of the rada rsensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the fron tofthe vehicle.
If BAS PLUS is not available due to a
malfunction in the radar sensor system, the
brake system remains available with full
brake boosting effect and BAS. ESP
®
(Electronic Stability Program)
Important safety notes i
See the "Important safety notes" section
(Y page 56).
If ESP ®
detects that the vehicle is deviating
from the direction desired by the driver, one
or more wheels are braked to stabilize the
vehicle. If necessary, the engine output is also
modified to keep the vehicle on the desired
course within physical limits. ESP ®
assists
the driver when pulling away on wet or
slippery roads. ESP ®
can also stabilize the
vehicle during braking.
If ESP ®
intervenes, the 000BESP®
warning
lamp flashes in the instrumentc luster.58
Driving safety systemsSafety

G
WARNING
Even if PRE-SAFE ®
Brake slows the vehicle
before an imminent rear-end collision, the
system cannot avert a collision without the
intervention of the driver. There is a risk of an
accident. Brake according to the situation or
take evasive action. Delayed intervention by
the driver can lead to an accident. G
WARNING
PRE-SAFE ®
Brake cannot always detect
comple xtraffic situations properly.
In these cases, PRE-SAFE(R) Brake may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
There is a risk of an accident. Always pay
particular attention to the traffic situation and
be ready to brake, especially if PRE-SAFE(R)
Brake warns you. Terminate the intervention
in a non-critical driving situation.
In particular, the detection of obstacles can
be impaired if there is:
R dirt on the sensors or anything else
covering the sensors
R snow or heavy rain
R interference by other rada rsources
R the possibility of strong radar reflections,
for example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line G
WARNING
PRE-SAFE ®
Brake does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R in curves
As a result, PRE-SAFE ®
Brake cannot
intervene in critical situations. There is a risk
of an accident .Always pay careful attention
to the traffic situation and be ready to brake. In order to maintain the appropriate distance
to the vehicle in front and thus prevent a
collision, you must apply the brakes yourself.
X
To activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer (Y page 190).
The 0001 symbol appears in the
multifunction display as long as the HOLD
function is not activate d(Ypage 168).
On vehicles with Parking Guidance, the
0001 symbol is displayed when Pis
engaged or is selected or if you drive faster
than 22 mph (35 km/h).
For PRE-SAFE ®
Brake to assist you when
driving, the radar senso rsystem mus tbe
switched on (Y page 194) and be
operational.
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle. Theft deterrent locking system
Immobilizer
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. The
engine can be started by anyone with a valid
SmartKey that is left inside the vehicle.
X To activate with the SmartKey: remove
the SmartKey from the ignition lock.
X To activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
i The immobilizer is always deactivated
when you start the engine.
In the event that the engine cannot be
started when the starter battery is fully
charged, the immobilizer may be faulty.
Contact an authorized Mercedes-Benz 64
Theft deterrent locking systemSafety

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Please read the information on qualified
specialist workshops (Y page 23).SmartKey
Important safety notes
G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. Achild's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function.
If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very hot, and a child could be burned on these
parts.
G
WARNING
If a key ring is too heavy or too large, the
weight acting on the key could cause it to turn
in the ignition lock or catch on the steering
wheel. This could cause the engine to be
switched off suddenly. You may lose control
of the vehicle and cause an accident. Do not
attach any heavy or large key rings to the key
that is inserted in the ignition. General notes
If you cannot lock or unlock the vehicle with
the SmartKey, either the battery in the
SmartKey is discharged, the SmartKey is
faulty or the starter battery is discharged.
X Check the battery in the SmartKey and
replace it if necessary (Y page 71).
X Unlock the driver's door using the
mechanical key (Y page 76).
X Lock the vehicle using the mechanical key
(Y page 76).
X Have the starter battery and the battery
contacts checked at a qualified specialist
workshop.
If the SmartKey is faulty, contact Roadside
Assistance or a qualified specialist workshop. SmartKey functions
The SmartKey centrally locks/unlocks:
R the doors
R the trunk lid
R the glove box
R the stowage compartment in the center
console
R the fuel filler flap 68
SmartKeyOpening/closing

0002
000F Locks the vehicle
0003 0006 Unlocks the trunk lid
0023 0010 Unlocks the vehicle
When unlocking, the turn signals flash once.
When locking, they flash three times.
When it is dark, the surround lighting also
comes on if it is activated in the on-board
computer (Y page 193).
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated using
the on-board computer (Y page 194).
X To unlockc entrally:press the0010
button.
If you do not open th evehicle within
approximately 40 seconds of unlocking:
R the vehicle is locked again.
R the thef tdeterrent locking system is armed
again.
X To lock centrally: press the000Fbutton. KEYLESS-GO
Important notes on the use of KEYLESS-
GO R
Do not keep the KEYLESS-GO key together
with:
- electronic devices, e.g. a mobile phone
or another key
- metallic objects, e.g. coins or metal foil. This can affect the functionality of
KEYLESS-GO.
R Bear in mind that the engine can be started
by any of the vehicle occupants if there is
a KEYLESS-GO key in the vehicle.
Locking and unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry
the SmartKey with you. You can combine the
KEYLESS-GO functions with those of a
conventional key, e.g. using KEYLESS-GO to
unlock and pressing the
000Fbutton to lock.
When locking and unlocking using KEYLESS-
GO, the distance between the SmartKey and
the corresponding door handle must not
exceed 3 ft (1 m).
KEYLESS-GO checks whether a valid key is in
the vehicle by periodically establishing a radio
connection between the vehicle and the key.
This happens:
R when the external door handles are
touched
R when starting the engine
R while the vehicle is in motion X
To unlock the vehicle: touch the inner
surface of the door handle.
X To lock the vehicle: touch sensor
surface 0002.
X Convenience closing feature: touch
recessed sensor surface 0003for an
extended period (Y page 81). SmartKey
69Opening/closing Z

Problem Possible causes/consequences and
0001 Solutions
The engine cannot be
started using the
SmartKey. The on-board voltage is too low.
X
Switch off non-essential consumers, e.g. seat heating or interior
lighting, and try to start the engine again.
If this does not work:
X Check the starter battery and charge it if necessary
(Y page 282).
or
X Jump-start the vehicle (Y page 285).
or
X Consult a qualified specialist workshop. The engine cannot be
started using KEYLESS-
GO. The SmartKey is in
the vehicle. Ad
oor is open. Therefore, the SmartKey cannot be detected as
easily.
X Close the door and try to start the vehicle again. There is interference from a powerful source of radio waves.
X
Start your vehicle with the SmartKey in the ignition lock. Doors
Important safety notes
G
WARNING
When leaving the vehicle, always remove the
SmartKey from the ignition lock. Always take
the SmartKey with you and lock the vehicle.
Do not leave children unsupervised in the
vehicle, even if they are secured in a child
restraint system, and do not give them access
to an unlocked vehicle. Achild's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. They could:
R injure themselves on vehicle parts
R be seriously or fatally injured by extreme
heat or cold
R injure themselves or have an accident with
vehicle equipment that may still be in
operation even after the SmartKey has
been removed from the ignition, such as the
seat adjustment, steering wheel
adjustment or memory function. If children open a door, they could cause
severe or even fatal injury to other persons; if
they get out of the vehicle, they could injure
themselves when doing so or be seriously or
even fatally injured by any passing traffic.
Do not expose the child restraint system to
direct sunlight. The child restraint system's
metal parts, for example, could become very
hot, and a child could be burned on these
parts. G
WARNING
Do not carry heavy or hard objects in the
passenger compartmentu nless they are
firmly secured in place.
Unsecured or improperly positioned cargo
increases a child's risk of injury in the event
of:
R strong braking maneuvers
R sudden changes of direction
R an accident 74
DoorsOpening/closing

Problems with the roof
Problem Possible causes/consequences and
0001 Solutions
The roof will not open or
close. The trunk partition is not closed and not properly engaged.
X
Close the trunk partition (Y page 85). The trunk lid is open.
X
Close the trunk lid (Y page 77). The on-board voltage is too low.
X
Leave the engine running. The roof has been opened and closed several times in
arow. The
roof drive has been automatically deactivated.
You can open and close the roof again after approximately ten
minutes.
X Switch off the ignition and turn it back on.
X Repeat the opening or closing procedure. The automatic roof mechanism is faulty.
X
Consult a qualified specialist workshop. Wind screen
General notes The wind screen offers protection from the
wind when driving with the roof down.
G
WARNING
You could lose control of the vehicle and
injure yourself or others if you operate the
wind screen while driving.
Install or remove the wind screen only when
the vehicle is stationary. G
WARNING
If you use the wind screen in darkness or in
other conditions offering poor visibility, your
view to the rear is further impaired. As a result
of the visibility impairment, you could cause
an accident and injure yourself or others.
For this reason, remove the wind screen as
soon as it is dark or if your vision is otherwise
restricted. G
WARNING
If the wind screen is not correctly engaged, it
may break free and thus obstruct traffic
behind you or lead to an accident.
Each time before driving with the roof down,
check that the wind screen is properly
engaged.
! Install or remove the wind screen only
when the roof is open. You could otherwise
damage the wind screen or the vehicle
interior.
The wind screen can be installed or removed
from the driver's side or passenger side.
Perform operations involving the wind screen
preferably on the side facing away from
traffic, after you have stopped the vehicle,
paying attention to road and traffic
conditions. 86
RoofOpening/closing