MERCEDES-BENZ SLK350 2012 R172 Workshop Manual

your ris
kofinjuries and thei rlikely severity in
an accident.
If you are ever in an accident, your injuries
could be considerably more severe if you have
not fastened your seat belt correctly. If you do
not fasten your seat belt, you are much more
likely to collide with part softhe vehicle
interior or be ejected from it. This may result
in serious or fatal injury.
In the same crash, the possibility of serious or
fatal injury is considerably reduced if you wear
your seat belt properly. The air bags can only
offer the intended protection if the occupants
are wearing their seat belts properly. G
WARNING
Never ride in a moving vehicle with the seat
backrest in an excessively reclined position as
this can be dangerous. You could slide under
the seat belt in a collision. If you slide under
it, the seat belt would apply force at the
abdomen or neck.T hat could cause serious
or even fatal injuries. The seat backrest and
seat belt provide the best restraint when the
wearer is in a position that is as upright as
possible and the seat belt is properly
positioned on the body. G
WARNING
Never let more people ride in the vehicle than
there are seat belts available. Make sure
everyone riding in the vehicle is correctly
restrained with a separate seat belt. Never
use a seat belt for more than one person at a
time. G
WARNING
Damaged seat belts or seat belts that have
been subjected to stress in an accident must
be replaced and their anchoring points must
also be checked.
Only use seat belts which have been approved
by Mercedes-Benz.
Do not make any modifications to the seat
belts. This can lead to unintended activation of the ETDs or to their failure to activate when
necessary.
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.
Have all work carried out only by qualified
technicians. Contact an authorized
Mercedes-Benz Center.
Correct use of the seat belts G
WARNING
USE SEAT BELTS PROPERLY
R Seat belts can only work when used
properly. Never wear seat belts in any other
way than as described in this section, as
that could result in serious injuries in the
event of an accident.
R Each occupant should wear their seat belt
at all times, because seat belts help reduce
the likelihood of and potential severity of
injuries in accidents, including rollovers.
The integrated restraint system includes
SRS (driver front air bag, knee bags, front-
passenger front air bag, side impact air
bags, head air bags), Emergency
Tensioning Devices (ETDs) and seat belt
force limiters. The system is designed to
enhance the protection offered to properly
belted occupants in certain frontal (front air
bags, knee bags and ETDs) and side (side
impact air bags, head air bags and ETDs)
impacts which exceed preset deployment
thresholds.
R Never wear the shoulder belt under your
arm, across your neck or off your shoulder.
In a frontal crash, your body would move
too far forward. That would increase the
chance of head and neck injuries. The seat
belt would also apply too much force to the
ribs or abdomen, which could severely
injure internal organs such as your liver or
spleen.
Adjust the seat belt so that the shoulder
section is located as close as possible to Occupant safety
49Safety
Z

the middle of the shoulde
r(it should not
touch the neck).
R Position the lap belt as low as possible on
your hips and not across the abdomen .If
the lap belt is positioned across your
abdomen, it could cause serious injuries in
a crash.
R Never wear seat belts ove rrigid or
breakable objects in or on your clothing,
such as eyeglasses, pens, keys etc., as
these might cause injuries.
R Make sure the seat belt is always fitted
snugly. Take special care of this when
wearing loose clothing.
R Never use a seat belt for more than one
person at a time. Do not fasten a seat belt
around a perso nand another perso nor
other objects at the same time.
R Seat belts should not be worn twisted. In a
crash, you would not have the full width of
the seat belt to distribute impact forces.
The twisted seat belt against your body
could cause injuries.
R Pregnant women should also always use a
lap-shoulder belt. The lap belt portion
should be positioned as low as possible on
the hips to avoid any possible pressure on
the abdomen.
R Place the seat backrest in a position that is
as upright as possible.
R Check your seat belt during travel to make
sure it is properly positioned.
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 When using a seat belt to secure infant
restraints, toddler restraints, or children in
booster seats, always follow the child seat
manufacturer's instructions. G
WARNING
Do not pass seat belts over sharp edges. They
could tear. Do not allow the seat belt to get caught in the
door or in the seat adjustment mechanism.
This could damage the seat belt.
Never attempt to make modifications to seat
belts. This could impair the effectiveness of
the seat belts.
Fastening seat belts G
WARNING
Children 12 years old and under must be
seated and properly secured in an
appropriately sized infant restraint, child
restraint system, or booster seat
recommended for the size and weight of the
child. For additional information, see the
"Children in the vehicle" section.
Ac hild's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint. X
Adjust the seat and move the backrest to
an almost vertical position (Y page 92).
X Pull the seat belt smoothly through belt
loop 0002.
X Without twisting it, guide the shoulder
section of the seat belt across the middle 50
Occupant safetySafety

of your shoulder and the lap section across
your hips.
X Engage belt tongue 0003in buckle 0023.
X If necessary, pull upwards on the shoulder
section of the seat belt to tighten the belt
across your body.
The seat belt on the front-passenger side is
equipped with a special seat belt retractor to
securely fasten a child restraint system in the
front-passenger seat. For further information
about special seat belt retractors, see
(Y page 55).
For more information about releasing the seat
belt with release button 0022, see "Releasing
seat belts" (Y page 51).
Seat belt adjustment i
AMG vehicles do not include the seat-belt
adjustment function.
The seat-belt adjustmen tfunction adjusts the
driver's and front-passenger seat belt to the
upper body of the occupants.
The belt strap is tightened slightly when:
R you engage the belt tongue in the belt
buckle and you then turn the SmartKey to
position 2in the ignition lock.
R the SmartKey is in position 2in the ignition
loc ka nd you then engage the belt tongue
in the buckle.
The seat-belt adjustment will apply a
retraction force if any slack is detected
between the occupant and the sea tbelt. Do
not hold on to the seat belt tightly while it is
adjusting. You can switch the seat-belt
adjustment on and off in the on-board
computer (Y page 194).
The seat-belt adjustment is an integral part of
the PRE-SAFE ®
convenience function. More
information about PRE-SAFE ®
can be found
in the "PRE-SAFE ®
(preventative occupant
protection)" section (Y page 47). Releasing seat belts X
Press release button 0022(Ypage 50) and
guide belt tongue 0003back towards belt
loop 0002.
! Make sure that the seat belt is fully rolled
up. Otherwise, the seat belt or belt tongue
will be trapped in the door or in the seat
mechanism. This could damage the door,
the door trim panel and the seat belt.
Damaged seat belts can no longer fulfill
their protective function and must be
replaced. Visit a qualified specialist
workshop.
Belt warning for the driver and front
passenger Regardless of whether the driver's and front-
passenger seat belts have already been
fastened, the
001Aseat belt warning lamp will
light up for six seconds each time the engine
is started. It then goes out if the driver and
the fron tpassenger have fastened their seat
belts.
If the driver's seat belt is no tfastened when
the engine is started, an additional warning
tone will sound. The warning tone goes out
after approximately six seconds or once the
driver's seat belt is fastened.
If after six seconds the driver's or front-
passenger seat belt is no tfastened and the
doors are closed, the 001Aseat belt warning
lamp will remain lit:
R until the driver's or fron tpassenger's seat
belt is fastened
R once the vehicle has exceeded a speed of
15 mph (25 km/h), in addition a warning
tone will sound with increasing intensity for
up to 60 seconds or until the driver's or
front-passenger seat belt is fastened.
If the driver or fron tpassenger unfastens their
seat belt during the journey, the 001Aseat
belt warning lamp lights up and the warning
tone sounds again. Occupant safety
51Safety Z

The warning tone ceases after 60 seconds
even if the driver or frontp
assenger has still
no tfastened their seat belt .The 001A seat
belt warning lamp stops flashing, but remains
lit.
After the vehicle has come to a stop, the
warning tone will be reactivated and the
001A seat belt warning lamp will flash again
once the vehicle has exceeded a speed of
15 mph (25 km/h).
The 001A seat belt warning lamp will not go
out until:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open.
i For more information on the 001Aseat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belt" (Y page 228).
Emergency Tensioning Devices, belt
force limiters The seat belts are equipped with ETDs and
seat belt force limiters.
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
Seat belt force limiters, when triggered, help
to reduce the peak force exerted by the seat
belt on the vehicle occupant.
The seat belt force limiters are synchronized
with the front air bags, which take on a part
of the deceleration force. Thus, the force
exerted on the occupant is distributed over a
greater area.
The ETDs can only be activated when:
R the ignition is switched on.
R the restraint systems are operational; see
"SRS warning lamp" (Y page 36).R
the belt tongue is engaged in the buckle on
each of the three-point seat belts.
R the front-passenger seat is occupied and
the belt tongue is engaged in the buckle on
the front-passenger side.
The ETDs are triggered depending on the type
and severity of an accident:
R if, in the event of a head-on or rear-end
collision, the vehicle decelerates or
accelerates rapidly in a longitudinal
direction during the initial stages of the
impact
R if, in the event of a side impact, the vehicle
is subjected to high lateral acceleration/
deceleration
R if, in certain situations where the vehicle
overturns, the system determines that it
can provide additional protection
If the air bags are deployed, you will hear a
bang, and a small amount of powder may also
be released. Only in rare cases will the bang
affect your hearing. The powder that is
released generally does not constitute a
health hazard. The 0019SRS warning lamp
lights up. G
WARNING
Pyrotechnic ETDs that were activated must be
replaced.
For your safety, when disposing of the
pyrotechnic ETDs always follow our safety
instructions. These are available at any
authorized Mercedes-Ben zCenter.
! If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device could be triggered in the
event of an accident. 52
Occupant safetySafety

Children in the vehicle
Child restraint systems
Important safety notes We recommend that all infants and children
be properly secured in an infant or child
restraint system at all times while the vehicle
is in motion.
The use of seat belts and infant and child
restraint systems is required by law in all 50
states, the District of Columbia, the U.S.
territories and all Canadian provinces.
Infants and childre nmust always be seated in
an appropriate infant or child restraint system
recommended for the size and weigh tofthe
child. The infant or child restraint system
must be properly secured with a three-point
seat belt in accordance with the
manufacturer's instructions. All infant or
child restraint systems must comply with U.S.
Federal Motor Vehicle Safety Standards 213
and 225 and CanadianM otor Vehicle Safety
Standards 213 and 210.2.
An information label on the child restraint
system indicates whether it meets these
standards. This information is also provided
in the installation instructions supplied with
the child restraint system.
Always read and follow the manufacturer's
instructions when using an infant or child
restraint system or booster seat.
Observe all warning signs in the vehicle
interior and on the infant or child restraint. G
WARNING
Children 12 years old and under must be
seated and properly secured in an appropriate
infant restraint, toddler restraint, or booster
seat recommended for the size and weight of
the child.
The infant or child restraint system must be
correctly secured using the vehicle's seat belt
in complete accordance with the child seat
manufacturer's instructions.
Occupants, in particular children, must sit as
upright as possible, fasten the seat belt correctly and use a suitable infant restraint
system, child restraint system or booster seat
suitable for the size and weight of the child.
Children can be seriously or even fatally
injured by an air bag deploying. Observe the
following information:
R
Your vehicle is equipped with air bag
technology designed to deactivate the
front-passenger front air bag in your vehicle
when the system senses the weight of a
typical 12-month-old child or less along
with the weight of a standard appropriate
child restraint on the passenger seat.
R Ac hild in a rearward-facing child restraint
system on the front-passenger seat could
be seriously injured or even killed if the
front-passenger air bag inflates in a
collision despite the air bag technology
installed in your vehicle, which could occur
under some circumstances.
R If you install a rearward-facing child
restraint on the front-passenger seat, make
sure that the 0015PASSENGER AIR BAG
OFF indicator lamp is illuminated,
indicating that the front-passenger front air
bag is deactivated. Should the 0015
PASSENGER AIR BAG OFF indicator lamp
not illuminate or go out while a rearward-
facing child restraint system is installed,
please check installation. Periodically
check the 0015PASSENGER AIR BAG OFF
indicator lamp while driving to make sure it
is illuminated. If the 0015PASSENGER AIR
BAG OFF indicator lamp goes out or
remains out, do not transport a child on the
front-passenger seat.
R Ac hild in a rearward-facing child restraint
system on the front-passenger seat can be
seriously injured or even killed if the front-
passenger air bag is deployed. Children in the vehicle
53Safety
Z

R
When securing a child in achild restraint
system on the front-passenger seat, you
must:
- move the front-passenger seat as far
back as possible
- use a child restraint system that is
suitable for the age, size and weight of
the child
- observe the manufacturer's installation
instructions in order to install and secure
the child restraint system correctly.
R For children larger than the typical 12-
month-old child, the front-passenger front
air bag may or may not be activated. G
WARNING
Infants and small children should never share
a seat belt with another occupant. In the event
of an accident, they could be crushed
between the occupant and seat belt.
Ac hild's risk of serious or fatal injuries is
significantly increased if the child restraints
are not properly secured in the vehicle and/
or the child is not properly secured in the child
restraint.
Children that are too large for a child restraint
must travel in seats using normal seat belts.
Position the shoulder belt across the chest
and shoulder, not face or neck.Ab ooster seat
may be necessary to achieve proper seat belt
positioning for children over 41 lb (18 kg) until
they reach a height where a lap-shoulder belt
fits properly without a booster.
When the child restraint is not in use, remove
it from the vehicle or secure it with the seat
belt to prevent the child restraint from
becoming a projectile in the event of an
accident.
If an infant or child is traveling in the vehicle:
X Secure the infant or child with an
appropriate infant or child restraint recommended for the child's age and
weight.
X Make sure that the infant or child is
properly secured at all times while the
vehicle is in motion. 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 unattended in the
vehicle, even if they are secured in a child
restraint system, or with access to an
unlocked vehicle. Achild's unsupervised
access to a vehicle could result in an accident
and/or serious personal injury. The children
could:
R injure themselves on parts of the vehicle
R be seriously or fatally injured through
excessive exposure to extreme heat or cold
R injure themselves or cause an accident with
vehicle equipment that can be operated
even if the SmartKey is removed from the
ignition lock or removed from the vehicle,
such as seat adjustment, steering wheel
adjustment, or the memory function
If children open a door, they could injure other
persons or get out of the vehicle and injure
themselves or be injured by following 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 the 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 54
Children in the vehicleSafety

Special seat belt retractor
The seat belt on the front-passenger side is
equipped with a special seat belt retractor.
When activated, the special seat belt
retractor ensures the seat belt will not
slacken once the child restraint system has
been secured.
Installing a child restraint system:
X Always comply with the manufacturer's
installation instructions.
X Pull the seat belt smoothly from the inertia
reel.
X Engage the seat belt tongue in the belt
buckle.
Activating the special seat belt retractor:
X Pull the seat belt out fully and let the inertia
reel retract it again.
While the seat belt is retracting, you should
hear a ratcheting sound. The special seat
belt retractor is enabled.
X Push down on the child restraint system to
take up any slack.
Removing a child restraint system/
deactivating the special seat belt retractor:
X Always comply with the manufacturer's
installation instructions.
X Press the seat belt release button and
guide the belt tongue to the belt outlet.
The special seat belt retractor is
deactivated. G
WARNING
Never release the seat belt buckle while the
vehicle is in motion, since the special seat belt
retractor will be deactivated. Panic alarm
X
To activate: press0011button 0002for at
least one second.
An alarm sounds and the exterior lighting
flashes.
X To deactivate: press0011button 0002
again.
or
X Insert the SmartKey into the ignition lock.
or
X Press the KEYLESS-GO Start/Stop button.
The KEYLESS-GO key must be in the
vehicle.
i USA only:
This device complies with Part 15 of the
FCC Rules. Operation is subject to the
following two conditions:
1. This device may not cause harmful
interference, and
2. this device must accept any interference
received, including interference that may
cause undesired operation.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey.
i Canada only:
This device complies with RSS-Gen of
Industry Canada.O peration is subjectto
the following two conditions: Panic alarm
55Safety Z

1. This device may not cause interference,
and
2. this device must accep
tany interference
received, including interference tha tmay
cause undesired operation.
Any unauthorized modificatio nto this
device could void the user's authority to
operate the equipment.
The product label with FCC ID and IC
certification number can be found in the
battery case of the SmartKey. Driving safety systems
Driving safety systems overview
In this section, you will find information about
the following driving safety systems:
R ABS (Anti-lock BrakingSystem)
R BAS (Brake AssistSystem)
R BAS PLUS ( BrakeAssist System Plus)
R ESP ®
(Electronic StabilityProgram)
R EBD ( Electronic Brake force Distribution)
R ADAPTIVE BRAKE
R PRE-SAFE ®
Brake Important safety notes
G
WARNING
The following factors increase the risk of
accidents:
R Excessive speed, especially in turns
R Wet and slippery road surfaces
R Following another vehicle too closely
The driving safety systems described in this
section cannot reduce these risks or prevent
the natural laws of physics from acting on the
vehicle. They cannot increase braking or
steering efficiency beyond that afforded by
the condition of the vehicle brakes and tires
or the traction afforded.
Only a safe, attentive, and skillful driver can
prevent accidents. The capabilities of a vehicle equipped with the
driving safety systems described in this
section must never be exploited in a reckless
or dangerous manner which could jeopardize
the user's safety or the safety of others.
Always adjust your driving style to the
prevailing road and weather conditions and
keep a safe distance to other road users and
objects on the street.
If a driving system malfunctions, other driving
safety systems may also switch off. Observe
indicator and warning lamps that may come
on as well as messages in the multifunction
display that may appear.
i Please note that the driving safety
systems described only work as effectively
as possible when there is adequate contact
between the tires and the road surface. Pay
particular attention to the information
regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and
tires" section (Y page 294).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible. ABS (Anti-lock Braking System)
Important safety notes i
Observe the "Important safety notes"
section (Y page 56).
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
ABS works from a speed of about 5 mph
(8 km/h) upwards, regardless of road-surface
conditions. ABS works on slippery surfaces,
even if you only brake gently. 56
Driving safety systemsSafety

G
WARNING
If the ABS malfunctions, other driving systems
such as the BAS or the ESP ®
are also switched
off. Observe indicator and warning lamps that
may come on as well as messages in the
multifunction display that may appear.
If the ABS malfunctions, the wheels may lock
during hard braking, reducing the steering
capability and extending the braking distance.
The 0014 warning lamp in the instrument
cluster lights up when the ignitio nis switched
on. It goes out when the engine is running.
Brakes If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
X If ABS intervenes: continue to depress the
brake pedal vigorously until the braking
situation is over.
X To make a full brake application:
depress the brake pedal with full force.
The pulsating brake pedal can be an
indication of hazardous road conditions, and
functions as a reminder to take extra care
while driving. G
WARNING
Do not pump the brake pedal.U se firm, steady
brake pedal pressure instead. Pumping the
brake pedal defeats the purpose of the ABS
and significantly reduces braking
effectiveness. BAS (Brake AssistS
ystem)
i Observe the "Important safety notes"
section (Y page 56).
BAS operates in emergency braking
situations. If you depress the brake pedal
quickly, BAS automatically boosts the braking
force, thus shortening the stopping distance.
X Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking. The brakes will function as usual once you
release the brake pedal. BAS is deactivated. G
WARNING
If the BAS malfunctions, the brake system still
functions, but without the additional brake
boost available that the BAS would normally
provide in an emergency braking maneuver.
Therefore, the braking distance may increase. BAS PLUS (Brake Assist System Plus)
BAS PLUS is only available in vehicles
equipped with DISTRONIC PLUS.
i Observe the "Important safety notes"
section (Y page 56).
BAS PLUS assists you when braking in a
hazardous situation at speeds of over
20 mph (30 km/h), and uses the radar sensor
system to assess traffic conditions.
i This device has been approved by the FCC
as a "Vehicular Radar System". The radar
sensor is intended for use in an automotive
radar system only. Removing, altering or
tampering with the device will void any
warranties, and is not permitted by the
FCC. Do not tamper with, alter, or use in
any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
With the help of the radar sensor system, BAS
PLUS can detect obstacles that are in the
path of yourv ehicle for an extended period of
time.
BAS PLUS can also react to stationary
obstacles, e.g. stopped or parked vehicles, at
speeds of up to approximately 40 mph
(70 km/h).
Should you approach an obstacle and BAS
PLUS has detected a risk of collision, BAS
PLUS calculates the brakin gforce necessary
to avoid a rear-end collision. Should you apply
the brakes forcefully, BAS PLUS can Driving safety systems
57Safety 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