2012 MERCEDES-BENZ SLK-CLASS ROADSTER brake

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 from your 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
GWARNING
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
GWARNING
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.
GWARNING
On slippery road surfaces, never downshift in
order to obtain braking action. This could
result in drive wheel slip and reduced vehicle
Driving tips155Driving and parkingZ

control. Your vehicle's ABS will not prevent
this type of loss of control.
Drive particularly carefully on slippery road
surfaces. Avoid sudden acceleration, steering
and braking maneuvers. Do not use cruise
control.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:XVehicles with manual transmission:
shift to neutral.XVehicles with automatic transmission:
shift the transmission to position N.
i
For more information on driving with
snow chains, see ( Y page 297).
GWARNING
Make sure that you do not endanger other
road users when you apply the brakes.
Driving systems
Cruise control
Important safety notes
Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. You must
select a low gear in good time on long and
steep downhill gradients, especially if the
vehicle is laden. Select shift range 1, 2 or 3
on vehicles with automatic transmission in
order to use the engine's braking effect,
which relieves the load on the brake system
and prevents the brakes from overheating
and wearing too quickly.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
store any road speed above 20 mph
(30 km/h).
GWARNING
The cruise control is a convenience system
designed to assist the driver during vehicle
operation. The driver is and must always
remain responsible for the vehicle's speed
and for safe brake operation.
Only use the cruise control if the road, traffic,
and weather conditions make it advisable to
travel at a constant speed.
R The use of the cruise control can be
dangerous on winding roads or in heavy
traffic because conditions do not allow safe
driving at a constant speed.
R The use of the cruise control can be
dangerous on slippery roads. Rapid
changes in tire traction can result in wheel
spin and loss of control.
R Deactivate the cruise control when driving
in fog.
The "Resume" function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.
Cruise control lever:To activate or increase speed;To activate or reduce speed=To deactivate cruise control?To activate at the current speed/last
stored speed
When you activate cruise control, the stored
speed is shown in the multifunction display
for five seconds. After that, it is permanently
shown in the status indicator:
R USA only: e.g., CRUISE 55Miles
R Canada only: e.g. ¯90 Km/h
156Driving systemsDriving and parking

Storing and maintaining the current
speed
You can store the current speed if you are
driving faster than 20 mph (30 km/h).
XAccelerate the vehicle to the desired
speed.XBriefly press the cruise control lever
up : or down ;.XRemove your foot from the accelerator
pedal.
Cruise control is activated. The vehicle
automatically maintains the stored speed.
i Cruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient
evens out. Cruise control maintains the
stored speed on downhill gradients by
automatically applying the brakes.
i Vehicles with manual transmission:
R Always drive at adequate, but not
excessive, engine speeds.
R Change gear in good time.
R If possible, do not shift down several
gears at a time.
Storing the current speed or calling up
the last stored speed
GWARNING
The set speed stored in memory should only
be set again if prevailing road conditions and
legal speed limits permit. Possible
acceleration or deceleration differences
arising from returning to the preset speed
could cause an accident and/or serious injury
to you and others.
XBriefly pull the cruise control lever towards
you ?.XRemove your foot from the accelerator
pedal.
The first time cruise control is activated, it
stores the current speed or regulates thespeed of the vehicle to the previously
stored speed.
Setting a speed
GWARNING
Keep in mind that it may take a brief moment
until the vehicle has made the necessary
adjustments.
Increase or decrease the set vehicle speed to
a value that the prevailing road conditions and
legal speed limits permit. Otherwise, sudden
and unexpected acceleration or deceleration
of the vehicle could cause an accident and/
or serious injury to you and others.
XPress the cruise control lever up : for a
higher speed or down ; for a lower speed.XTo adjust the speed in 1 mph
increments (1 km/h increments): briefly
press the cruise control lever up : or
down ; to the pressure point.
The last speed stored is increased or
decreased every time the cruise control
lever is pushed up : or down ;.XTo adjust the speed in 5 mph
increments (10 km/h increments):
briefly press the cruise control lever
up : or down ; beyond the pressure
point.
The last speed stored is increased or
decreased every time the cruise control
lever is pushed up : or down ;.
i
Cruise control is not deactivated if you
depress the accelerator pedal. For
example, if you accelerate briefly to
overtake, cruise control adjusts the
vehicle's speed to the last speed stored
after you have finished overtaking.
Driving systems157Driving and parkingZ

Deactivating cruise control
There are several ways to deactivate cruise
control:
XBriefly press the cruise control lever
forwards =.
or
XBrake.
Cruise control is automatically deactivated if:
R you engage the electric parking brake.
R you are driving at less than 20 mph
(30 km/h)
R ESP ®
intervenes or you deactivate ESP ®
.
R you shift into neutral in a vehicle with
manual transmission while driving or
depress the clutch pedal for longer than six
seconds.
R on vehicles with manual transmission, you
shift to a gear that is too high, and as a
result the engine speed is too low.
R on vehicles with automatic transmission,
you shift into position N while driving.
If cruise control is deactivated, you will hear
a warning tone. You will see the Cruise
Control Off message in the multifunction
display for approximately five seconds.
i When you switch off the engine, the last
speed stored is cleared.
DISTRONIC PLUS
Important safety notes
i DISTRONIC PLUS is not available on AMG
vehicles.
DISTRONIC PLUS regulates the speed and
automatically helps you maintain the
distance to the vehicle detected in front.
DISTRONIC PLUS brakes automatically so
that the set speed is not exceeded.
On long and steep downhill gradients,
especially if the vehicle is laden, you must
select shift range 1, 2 or 3 in good time. By
doing so, you will make use of the braking
effect of the engine, which relieves the load
on the brake system and prevents the brakes
from overheating and wearing too quickly.
If DISTRONIC PLUS detects a slower-moving
vehicle in front, your vehicle is braked in order
to maintain the preset distance to the vehicle
in front.GWARNING
The DISTRONIC PLUS requires familiarity with
its operational characteristics. We strongly
recommend that you review the following
information carefully before operating the
system.
GWARNING
The DISTRONIC PLUS is a convenience
system. Its speed adjustment reduction
capability is intended to make cruise control
more effective and usable when traffic speeds
vary. It is not however, intended to, nor does
it, replace the need for extreme care.
The responsibility for the vehicle's speed,
distance to the preceding vehicle and, most
importantly, brake operation to ensure a safe
stopping distance, always remains with the
driver.
The DISTRONIC PLUS cannot take street and
traffic conditions into account.
Complex driving situations are not always
fully recognized by the DISTRONIC PLUS. This
could result in wrong or missing distance
warnings.
If you want DISTRONIC PLUS to assist you,
the radar sensor system must be activated
( Y page 194) and operational.
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control in the speed range between 20 mph
(Canada: 30 km/h) and 120 mph (Canada:
200 km/h). If a vehicle is driving in front of
you, it operates in the speed range between
0 mph (0 km/h) and 120 mph (Canada:
200 km/h).
Do not use DISTRONIC PLUS while driving on
roads with steep gradients.
158Driving systemsDriving and parking

As DISTRONIC PLUS transmits radar waves,
it can resemble the radar detectors of the
responsible authorities. You can refer to the
relevant chapter in the Operator's Manual if
questions are asked about this.
i USA only:
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. Removal, tampering, or
altering of 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.
i Canada only: This device complies with
RSS-210 of Industry Canada. Operation is
subject to the following two conditions:
1. This device may not cause interference,
and
2. this device must accept any interference
received, including interference that may
cause undesired operation of the device.
Removal, tampering, or altering of the
device will void any warranties and is not
permitted. Do not tamper with, alter, or use
the device in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.GWARNING
DISTRONIC PLUS distance is not a substitute
for the active intervention of the driver. It does
not detect pedestrians or stationary objects,
nor can it detect, recognize or predict the
road's course or the movements of vehicles
in front. DISTRONIC PLUS can only brake the
vehicle using 40% of the vehicle's maximum
available brake force.
DISTRONIC PLUS may not detect narrow
vehicles driving in front, e.g. motorcycles, or
vehicles driving in the lane beyond the lane
next to your vehicle, especially if the vehicles
are not driving on the middle of their lane.
The driver must always pay careful attention
to the road, weather and traffic conditions.
The driver must drive, steer and brake in a
manner which will allow him to always have
control of the vehicle.
Sources of high-frequency radio waves, such
as toll stations, speed-measuring radar, etc.,
can cause DISTRONIC PLUS to fail
temporarily.GWARNING
The DISTRONIC PLUS cannot take road and
traffic conditions into account. Only use the
DISTRONIC PLUS if the road, weather and
traffic conditions make it advisable to travel
at a constant speed.
GWARNING
Use of the DISTRONIC PLUS can be
dangerous on slippery roads. Rapid changes
in tire traction can result in wheel spin and
loss of control.
The DISTRONIC PLUS does not function in
adverse sight and distance conditions. Do not
use the DISTRONIC PLUS during conditions of
fog, heavy rain, snow or sleet.
GWARNING
The DISTRONIC PLUS cannot take weather
conditions into account. Switch off the
DISTRONIC PLUS or do not switch it on if:
R roads are slippery or covered with snow or
ice. The wheels could lose traction while
braking or accelerating, and the vehicle
could skid.
R the DISTRONIC PLUS system sensor covers
are dirty or visibility is diminished due to
snow, rain or fog, for example. The distance
control system functionality could be
impaired.
Always pay attention to surrounding traffic
conditions even while the DISTRONIC PLUS is
switched on. Otherwise, you may not be able
to recognize dangerous situations until it is
Driving systems159Driving and parkingZ

too late. This could cause an accident in which
you and/or others could be injured.GWARNING
The "Resume" function should only be
operated if the driver is fully aware of the
previously set speed and wishes to resume
this particular preset speed.
GWARNING
Your undivided attention to street and traffic
conditions is necessary at all times whether
DISTRONIC PLUS is active or not.
The use of DISTRONIC PLUS can be
dangerous on winding roads or in heavy traffic
because conditions do not allow safe driving
at a constant speed.
DISTRONIC PLUS does not react to stationary
objects on the road (for example, a vehicle
stopped in traffic or an abandoned vehicle).
DISTRONIC PLUS likewise does not react to
oncoming vehicles.
Deactivate DISTRONIC PLUS:
R when changing to the right lane, if the
vehicles in the left lane are driving slower
R when driving into a filter lane or an
expressway exit
R in complex driving situations, for example
in construction sites on an expressway
In these situations DISTRONIC PLUS will
maintain the set speed if it is not deactivated.
DISTRONIC PLUS is intended only for
maintaining a set speed and a set distance
from the objects moving in front of the
vehicle.
GWARNING
An intermittent warning sounds and the
distance warning lamp · in the instrument
cluster is illuminated if the DISTRONIC PLUS
system calculates that the distance to the
vehicle ahead and your vehicle's current
speed indicate that the DISTRONIC PLUS will
not be capable of slowing the vehicle
sufficiently to maintain the preset following
distance, which creates a danger of a
collision.
Immediately brake the vehicle to increase
your distance to the preceding vehicle. The
warning sound is intended as a final caution
in which you should intercede with your own
braking inputs to avoid a potentially
dangerous situation. Do not wait for the
operation of the warning signal to intercede
with your own braking. This will result in
potentially dangerous emergency braking
which will not always result in an impact being
avoided.
Tailgating increases the risk of an accident.GWARNING
DISTRONIC PLUS brakes your vehicle with a
maximum deceleration of 13 ft/s 2
(4 m/s 2
).
This corresponds to approximately 40% of
your vehicle's maximum braking force.
To avoid a collision, you must apply the brakes
yourself. DISTRONIC PLUS brakes the vehicle
just enough to restore the preset speed or the
preset distance to the vehicle in front.
GWARNING
If you do not receive visual or acoustic
warning signals during a critical traffic
situation, DISTRONIC PLUS has either not
recognized the collision risk, has been
deactivated or is malfunctioning.
Remember, whether or not DISTRONIC PLUS
is operating, it is ultimately always the drivers
responsibility to apply the brakes in order to
control the vehicle and avoid a collision.
160Driving systemsDriving and parking

Cruise control lever:To store the current speed or a higher
speed;To store the current speed or a lower
speed=To deactivate DISTRONIC PLUS?Storing the current speed or calling up the
last stored speedASetting the specified minimum distance
Switching on DISTRONIC PLUS, storing
and maintaining the current speed
Important safety notes
GWARNING
The vehicle can be braked when DISTRONIC
PLUS is activated. For this reason, deactivate
DISTRONIC PLUS if the vehicle is to be set in
motion by other means (e.g. in a car wash or
by towing).
In order to activate DISTRONIC PLUS, the
following conditions must be fulfilled:
R the engine must be started. It may take up
to two minutes after pulling away before
DISTRONIC PLUS is operational.
R the electric parking brake must be
released.
R ESP ®
must be active, but not intervening.
R the transmission must be in position D.
R the hood must be closed.
R the driver's door must be closed when you
shift from P to D or your seat belt must be
fastened.
R the front-passenger door must be closed.
R the vehicle must not skid.
Activating while driving
When driving at speeds below 20 mph
(30 km/h ), you can only activate DISTRONIC
PLUS if the vehicle in front has been detected
and is shown in the multifunction display. If
the vehicle in front is no longer detected and
displayed, DISTRONIC PLUS switches off and
a tone sounds.XBriefly pull the cruise control lever towards
you ?, or press it up : or down ;.
DISTRONIC PLUS is selected.XPress the cruise control lever repeatedly
up : or down ; until the desired speed
is set.XRemove your foot from the accelerator
pedal.
Your vehicle adapts its speed to that of the
vehicle in front, but only up to the desired
stored speed.
i If you do not fully release the accelerator
pedal, the DISTRONIC PLUS Passive
message appears in the multifunction
display. The set distance to a slower-
moving vehicle in front will then not be
maintained. You will be driving at the speed
you determine by the position of the
accelerator pedal.
Activating when driving towards a
stationary vehicle
If the vehicle in front of you is stationary, you
can only activate DISTRONIC PLUS once your
vehicle is stationary as well.
XBriefly pull the cruise control lever towards
you ?, or press it up : or down ;.
DISTRONIC PLUS is selected.
i DISTRONIC PLUS can only be activated at
under 20 mph ( 30km/h) if a vehicle in front
has been detected. Therefore, the
DISTRONIC PLUS distance display in the
instrument cluster should be activated
( Y page 190).
Driving systems161Driving and parkingZ

XPress the cruise control lever repeatedly
up : or down ; until the desired speed
is set.
i You can use the cruise control lever to set
the stored speed and the control on the
cruise control lever to set the specified
minimum distance ( Y page 164).
Pulling away
XIf the vehicle in front pulls away: remove
your foot from the brake pedal.XBriefly pull the cruise control lever towards
you ?.
or
XAccelerate briefly.
Your vehicle pulls away and adapts its
speed to that of the vehicle in front.
Driving
If there is no vehicle in front, DISTRONIC
PLUS operates in the same way as cruise
control.
If DISTRONIC PLUS detects that the vehicle
in front has slowed down, it brakes your
vehicle. In this way, the distance you have
selected is maintained.
If DISTRONIC PLUS detects that the vehicle
in front is driving faster, it accelerates your
vehicle, but only up to the speed you have
stored.
GWARNING
If you depress the brake, DISTRONIC PLUS is
deactivated unless your vehicle is stationary.
DISTRONIC PLUS then no longer brakes your
vehicle. In such cases, control the distance
from vehicles travelling in front with the brake
alone. You could otherwise cause an accident
and thereby injure yourself and others. The
driver remains fully responsible for the
vehicle's distance from other vehicles, the
speed being driven and for braking in good
time.
Changing lanes
If you change to the passing lane, DISTRONIC
PLUS supports you when:
R you are driving faster than 40mph
(60 km/h).
R DISTRONIC PLUS is maintaining the
distance to a vehicle in front.
R you switch on the appropriate turn signal.
R DISTRONIC PLUS does not detect a danger
of collision.
If these conditions are fulfilled, your vehicle
is accelerated. Acceleration will be
interrupted if changing lanes takes too long
or if the distance between your vehicle and
the vehicle in front becomes too small.
i When changing lanes, DISTRONIC PLUS
monitors the left lane on left-hand drive
vehicles and the right lane on right-hand
drive vehicles.GWARNING
DISTRONIC PLUS is only an aid designed to
assist driving.
It is not a substitute for attentive driving. The
driver remains fully responsible for the
vehicle's distance from other vehicles, the
vehicle's speed and for braking in good time.
Always pay attention to traffic conditions and
your surroundings. Otherwise, you may fail to
recognize dangers in time, cause an accident
and injure yourself and others.
Stopping
GWARNING
Never get out of the vehicle when DISTRONIC
PLUS is activated.
DISTRONIC PLUS must also never be
operated, activated or deactivated by a
passenger or from outside the vehicle.
DISTRONIC PLUS does not replace the
electric parking brake and must not be used
for parking.
162Driving systemsDriving and parking