2012 MERCEDES-BENZ CL-Class brake light

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.
Limited braking performance on salt
treated roadsGWARNING
The layer of salt on the brake discs and the
brake pads/linings may cause a delay 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 distance to 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 an authorized Mercedes-Benz
Center.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. This work
should be carried out at an authorized
Mercedes-Benz Center.
Have the brake pads replaced and the brake
fluid renewed at a qualified specialist
workshop, e.g. an authorized Mercedes-Benz
Center.GWARNING
If brake pads or brake fluid other than those
recommended are used, the braking
properties of the vehicle can be degraded to
an extent that safe braking is substantially
impaired. This could result in an accident.
! Vehicles with 4MATIC: function or
performance tests may only be carried out
on a 2-axle dynamometer. If you are
planning to have the vehicle tested on such
a dynamometer, contact an authorized
Mercedes-Benz Center to obtain further
information first. Otherwise, you could
damage the drive train or the brake system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition must be switched off
(SmartKey in position 0 or 1 in the ignition
lock or Start/Stop button in position 0 or
1 ) when the electric parking brake is being
tested on a brake dynamometer.
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
! Vehicles with 4MATIC: as the ESP®
system operates automatically, the engine
and the ignition system must be switched
off (SmartKey in position 0 or 1 in the
ignition lock or Start/Stop button in
position 0 or 1) when:
R testing the electric parking brake on a
brake dynamometer.
R you intend to have the vehicle towed with
one of the axles raised.
288Driving tipsDriving and parking

by the engine's air suction nozzles and this
can cause engine damage.
Winter driving
General 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.
At the onset of winter, have your vehicle
winterproofed at a qualified specialist
workshop, e.g. at an authorized Mercedes-
Benz Center.
Observe the notes in the "Winter operation"
section ( Y page 444).
Driving with summer tires
Observe the notes in the "Winter operation"
section ( Y page 444).
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
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 or DISTRONIC PLUS.
If the vehicle threatens to skid or cannot be
stopped when moving at low speed:XShift the transmission to position N.
i
For more information on driving with
snow chains, see ( Y page 445).
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. 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.
Use cruise control only if road and traffic
conditions make it appropriate to maintain a
steady speed for a prolonged period. You can
set 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.
290Driving systemsDriving and parking

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 switch on or to increase the speed;To switch on or to reduce the speed=To deactivate cruise control?To switch on with the current speed or
with the last stored speed
When you activate cruise control, the stored
speed is shown in the multifunction display
for five seconds and is indicated in the
speedometer by a triangle. The speedometer
dial lights up between the set speed and the
maximum speed.
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 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.
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 the
speed of the vehicle to the previously
stored speed.Driving systems291Driving and parkingZ

DISTRONIC PLUS displays in the
speedometer
When you switch on DISTRONIC PLUS,
triangle ; shows the stored speed.
i For design reasons, the speed displayed
in the speedometer may differ slightly from
the speed set for DISTRONIC PLUS.
If DISTRONIC PLUS detects a vehicle in front,
the speedometer dial lights up between
speed of the vehicle in front : and stored
speed ;.
DISTRONIC PLUS displays in the
multifunction display
General notes
You can select the distance display in the
Assistance menu ( Y page 341) of the on-
board computer.
Display when DISTRONIC PLUS is
deactivated
XSelect the Distance Display function
using the on-board computer
( Y page 341).
When DISTRONIC PLUS is deactivated, you
will see the following in the multifunction
display:
:Symbol for activated PRE-SAFE ®
Brake;Vehicle in front, if detected=Distance indicator, current distance to
the vehicle in front?Specified minimum distance to the
vehicle in front; adjustableAOwn vehicle
Display when DISTRONIC PLUS is
activated
XSelect the Distance Display function
using the on-board computer
( Y page 341).
You will see the stored speed for about five
seconds when you activate DISTRONIC PLUS.
After this time, you will see the following in
the multifunction display while DISTRONIC
PLUS is activated:
:DISTRONIC PLUS activated;Own vehicle=Specified minimum distance to the
vehicle in front; adjustable?Vehicle in front, if detectedDriving systems299Driving and parkingZ

Obstructions and stationary vehicles
DISTRONIC PLUS does not brake for
obstacles or stationary vehicles. If, for
example, the detected vehicle turns a corner
and reveals an obstacle or stationary vehicle,
DISTRONIC PLUS will not brake for these.
Crossing vehicles
DISTRONIC PLUS may mistakenly detect
vehicles that are crossing your lane.
Activating DISTRONIC PLUS at traffic lights
with crossing traffic, for example, could cause
your vehicle to pull away unintentionally.
HOLD function
General notes
The HOLD function can assist the driver in the
following situations:
R when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away.
Activation conditions
You can activate the HOLD function if:
R the vehicle is stationary.
R the driver's door is closed or your seat belt
is fastened.
R the electric parking brake is released.
R the hood is closed.
R the transmission is in position R, N or D.
The trunk lid must be closed in position R.
R DISTRONIC PLUS is deactivated.
Activating the HOLD function
XMake sure that the activation conditions
are met.XDepress the brake pedal.XQuickly depress the brake pedal further
until HOLD display : appears in the
instrument cluster.
The HOLD function is activated. You can
release the brake pedal.
i If depressing the brake pedal the first
time does not activate the HOLD function,
wait briefly and then try again.
GWARNING
The vehicle's brakes are applied when the
HOLD function is activated. For this reason,
deactivate the HOLD function if the vehicle is
to be set in motion by other means (e.g. in a
car wash or by towing).
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Ultrasonic sources such as an automatic
car wash, the compressed-air brakes on a
truck or a pneumatic drill could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on
uneven terrain.
Minimum distanceCenterApproximately 8 in
(approximately 20 cm)CornersApproximately 8 in
(approximately 20 cm)
If there is an obstacle within this range, the
relevant warning displays light up and a
warning tone sounds. If the distance falls
below the minimum, the distance may no
longer be shown.
Warning displays
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is in the
instrument cluster. The warning display for
the rear area is located on the headliner in the
rear compartment.
Warning display for the front area
:Segments on the left-hand side of the
vehicle;Segments on the right-hand side of the
vehicle=Segments showing operational readiness
The warning display for each side of the
vehicle is divided into five yellow and two red
segments. PARKTRONIC is operational if
yellow segments showing operational
readiness = light up.
The selected transmission position
determines which warning display is active
when the engine is running.Transmission
positionWarning displayDFront area activatedRRear and front areas
activatedNIf the electric parking
brake is engaged: no
areas are activated
If the electric parking
brake is released:
rear and front areas
are activatedPNo areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the
vehicle's distance from the obstacle.
When the first red segment lights up, you hear
an intermittent warning for about two
seconds. From the second red segment, you
hear a continuous warning. This indicates that
you have now reached the minimum distance.
Deactivating/activating PARKTRONIC
:To deactivate/activate PARKTRONIC;Indicator lamp308Driving systemsDriving and parking

Due to the nature of the system:
R warnings may be issued in error when
driving close to crash barriers or similar
solid lane borders.
R warnings may be interrupted when driving
alongside long vehicles, such as trucks, for
a prolonged time.
Two Active Blind Spot Assist radar sensors
are integrated into the front and rear bumpers
respectively. An additional radar sensor is
located behind the cover in the radiator grill.
Make sure that the sensor areas on the
bumpers and the sensor cover in the radiator
grill are free of dirt, ice and slush. The rear
sensors must not be covered, for example by
cycle racks or overhanging cargo. Following
a severe impact or in the event of damage to
the bumpers, have the function of the radar
sensors checked at a qualified specialist
workshop. Blind Spot Assist may otherwise
not work properly.
Indicator and warning display:Yellow indicator lamp/red warning lamp
When Active Blind Spot Assist is activated,
indicator lamp : lights up yellow in the
exterior mirrors up to a vehicle speed of
20 mph (30 km/h). When the vehicle speed
exceeds 20 mph (30 km/h), the indicator
lamp goes out and Active Blind Spot Assist is
ready for use.
When your speed exceeds approximately
20 mph (30 km/h), warning lamp : lights up
red on the corresponding side whenever a
vehicle is detected in the blind spot
monitoring range. This warning is always
given when a vehicle enters the blind spot
monitoring range from behind or from the
side. When you are passing another vehicle,
the warning is emitted only if the difference
in speed is less than 7 mph (12 km/h).
The yellow indicator lamp goes out if reverse
gear is engaged. In this event, Active Blind
Spot Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.GWARNING
Active Blind Spot Assist is not active at speeds
lower than 20 mph (30 km/h). The indicator
lamps in the exterior mirrors are yellow.
Vehicles in the monitoring range are then not
indicated.
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.
Visual and audible collision warnings
If you switch on the appropriate turn signals
and a vehicle is detected in the side
monitoring range, you will receive a visual and
acoustic collision warning. You will hear a
double warning tone and red warning
lamp : flashes. If the turn signal remains on,
vehicles detected are indicated by the
flashing of red warning lamp :. There are no
further warning tones.
Course-correcting brake application
If Active Blind Spot Assist detects a risk of a
lateral collision in the monitoring range, a
course-correcting brake application is carried
out. This is meant to assist you in avoiding a
collision.
The course-correcting brake application is
available in the range between 20 mph
(30 km/h) and 120 mph (200 km/h).
If a course-correcting brake application
occurs, red warning lamp : flashes in the
Driving systems323Driving and parkingZ

exterior mirror and the following is shown in
the multifunction display, for example:GWARNING
Active Blind Spot Assist is only an aid
designed to assist driving. It is not a substitute
for attentive driving. In some cases, the
course-correcting brake application is not
sufficient to avoid a collision. In such a case,
you must steer, brake or accelerate.
In very rare cases, the system may
erroneously detect a danger of collision in the
area of crash barriers or similar lane borders
and apply the brakes. Active Blind Spot Assist
does not detect all traffic situations and road
users. Always make sure that there is
sufficient distance on the side for other traffic
or obstacles. An inappropriate brake
application may be interrupted at any time if
you steer slightly in the opposite direction or
accelerate.
You are responsible for driving at appropriate
speeds, braking in good time, and steering
correctly. Always adapt your driving style to
suit the prevailing road and weather
conditions. 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.
There will be either no or only a weak course-
correcting brake application if:
R there are vehicles or obstacles, e.g. crash
barriers, located on both sides of your
vehicle.
R a vehicle approaches you too closely at the
side.
R you have adopted a sporty driving style with
high cornering speeds.
R you clearly brake or accelerate.
R a driving safety system intervenes, e.g.
ESP ®
or PRE-SAFE ®
Brake.
R ESP ®
is switched off.
R a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot AssistXMake sure that the radar sensor system
( Y page 344) and Active Blind Spot Assist
( Y page 343) are activated in the on-board
computer.XTurn the SmartKey to position 2 in the
ignition lock.
Warning lamps : light up red in the
exterior mirrors for approximately 1.5
seconds and then turn yellow.
Active Lane Keeping Assist
Important safety notes
Active Lane Keeping Assist monitors the area
in front of your vehicle by means of a camera
at the top of the windshield. Active Lane
Keeping Assist detects lane markings on the
road and warns you before you leave your
lane unintentionally. If you do not react to the
warning, a lane-correcting application of the
brakes can bring the vehicle back into the
original lane.
:Active Lane Keeping Assist camera
If you have selected the Display Unit
Speed-/Odometer (Y page 344) function in
the on-board computer and select km as the
unit of measurement, Active Lane Keeping
324Driving systemsDriving and parking