steering MERCEDES-BENZ CLS 2012 Service Manual

conditions. Additionally, the driver must
provide the steering, braking and other driving
inputs necessary to remain in control of the
vehicle.
High-frequency sources such as toll stations,
speed measuring systems etc. can cause the
DISTRONIC PLUS system to temporarily
cease functioning.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
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
at roadworks 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.
158Driving systemsDriving and parking

same travel direction is detected (e.g.
following another vehicle ahead of you at your
set distance).
This means that:
R Your vehicle can pass another vehicle after
you have changed lanes.
R While in a sharp turn or if the preceding
vehicle is in a sharp turn, the DISTRONIC
PLUS could lose sight of the preceding
vehicle. Your vehicle could then accelerate
to the previously selected speed.
The DISTRONIC PLUS regulates only the
distance between your vehicle and those
directly ahead of it. It may not register
stationary objects in the road, e.g.:
R a stopped vehicle in a traffic jam
R a disabled vehicle
R an oncoming vehicle
The driver must always be alert, observe all
traffic and intercede as required by means of
steering or braking the vehicle.GWARNING
The DISTRONIC PLUS should not be used in
snowy or icy road conditions.
Cornering, going into and coming out of a
bend
The ability of DISTRONIC PLUS to detect
vehicles when cornering is limited. Your
vehicle may brake unexpectedly or late.
Vehicles traveling on a different line
DISTRONIC PLUS may not detect vehicles
traveling on a different line. The distance to
the vehicle in front will be too short.
Other vehicles changing lane
DISTRONIC PLUS has not detected the
vehicle cutting in yet. The distance to this
vehicle will be too short.
Narrow vehicles
DISTRONIC PLUS has not yet detected the
vehicle in front on the edge of the road,
Driving systems165Driving and parkingZ

Rthe steering wheel is in the straight-ahead
position.
R the vehicle is stationary and the brake
pedal is depressed (left foot).
R the transmission is in position D.
Activating RACE STARTXDepress the brake pedal with your left foot,
and keep it depressed.XTurn the drive program selector clockwise
( Y page 143) until the RS lamp lights up.
The multifunction display shows the RACE
START Confirm: Paddle UP Cancel:
Paddle DOWN message.
i
If the conditions for activation are no
longer fulfilled, RACE START is canceled.
The multifunction display shows the RACE
START canceled message.
XTo cancel: pull the left steering wheel shift
paddle ( Y page 144).
or
XTo confirm: pull the right steering wheel
shift paddle ( Y page 144).
The multifunction display shows the RACE
START available Depress
accelerator message.
i
If you do not depress the accelerator
pedal fully within two seconds, RACE
START is canceled. The multifunction
display shows the RACE START not
possible See Operator's Manual
message.
XDepress the accelerator pedal fully.
The engine speed increases to
approximately 4000 rpm.
The multifunction display shows the RACE
START Release brake to start
message.
i If you do not release the brake pedal
within seven seconds, RACE START is
canceled. The multifunction display shows
the RACE START canceled message.XTake your foot off the brake, but keep the
accelerator pedal depressed.
The vehicle pulls away at maximum
acceleration.
The multifunction display shows the RACE
START active message.
RACE START is deactivated when a speed of
approximately 30 mph (Canada: 50 km/h) is
reached. Drive program S+ is activated.
SPORT handling mode remains activated.
RACE START is deactivated immediately if
you release the accelerator pedal during
RACE START or if any of the activation
conditions are no longer fulfilled. The
multifunction display shows the RACE START
not possible See Operator's Manual
message.
i If RACE START is used repeatedly within
a short period of time, it is only available
again after the vehicle has been driven a
certain distance.
AIRMATIC
Vehicle level
Important safety notes
Your vehicle regulates its height
automatically. All-round self-leveling ensures
the best possible suspension and constant
ground clearance, even with a laden vehicle.
When you drive fast, the vehicle is lowered
automatically to improve driving safety and to
reduce fuel consumption.
The following vehicle levels are possible:
R normal
R raised: the vehicle is raised by about 0.80 in
(20 mm) when compared with the normal
level
R lowered: the vehicle is lowered by about
0.40 in (10 mm) when compared with the
normal level
168Driving systemsDriving and parking

Problems with PARKTRONICProblemPossible causes/consequences and M SolutionsOnly the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is
deactivated after
approximately
20 seconds, and the
indicator lamp in the
PARKTRONIC button
lights up.PARKTRONIC has malfunctioned and has switched off.XIf problems persist, have PARKTRONIC checked at a qualified
specialist workshop.Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is
deactivated after
approximately 20
seconds.The PARKTRONIC sensors are dirty or there is interference.XClean the PARKTRONIC sensors ( Y page 289).XSwitch the ignition back on.The problem may be caused by an external source of radio or
ultrasound waves.XSee if PARKTRONIC functions in a different location.Active Parking Assist
Important safety notes
Active Parking Assist is an electronic parking
aid with ultrasound. Ultrasound is used to
measure the road on both sides of the vehicle.
A suitable parking space is indicated by the
parking symbol. Active steering intervention
can assist you during parking. You may also
use PARKTRONIC ( Y page 171). When
PARKTRONIC is switched off, Active Parking
Assist is also unavailable.
GWARNING
Active Parking Assist is merely an aid and may
sometimes recommend parking spaces that
are not suitable for parking. For example,
these might be spaces where parking is
prohibited, driveways, unsuitable surfaces,
etc.
Active Parking Assist measures the parking
space as you drive past it. Any later changes
to the parking space are not taken into
account. For instance, this may be the case
when the vehicle parked in front of or behind
the space changes its position or when an
obstacle is moved into the parking space.
Active Parking Assist does not relieve you of
the responsibility of paying attention. If you
rely solely on Active Parking Assist, you could
cause an accident and injure yourself and
others.
You are always responsible for safety and
must continue to pay attention to your
immediate surroundings when parking and
maneuvering.Driving systems175Driving and parkingZ

GWARNING
Objects located above the height range of
Active Parking Assist will not be detected
when the parking space is measured. These
are not taken into account when the parking
procedure is calculated, e.g. overhanging
loads, tail sections or loading ramps of goods
vehicles. In some circumstances, Active
Parking Assist may therefore guide you into
the parking space too early. This may lead to
a collision. For this reason, you should avoid
using Active Parking Assist in such situations.
GWARNING
The front of the vehicle will veer out in the
direction of the oncoming traffic during the
parking operation. In some cases, the vehicle
will also take you onto sections of the
oncoming lane during the parking procedure.
You are responsible for safety at all times and
must pay attention to any road users
approaching or passing. Stop the vehicle if
necessary or cancel the Active Parking Assist
parking procedure.
GWARNING
Make sure no persons or animals are in or
near the area in which you are parking/
maneuvering. Otherwise, they could be
injured.
Use Active Parking Assist for parking spaces:
R that are parallel to the direction of travel
R that are on straight roads, not bends
R that are on the same level as the road, e.g.
not on the pavement
Parking tips:
R on narrow roads, drive past the parking
space as close as possible.
R parking spaces that are littered, overgrown
or partially occupied by trailer drawbars
might be identified incorrectly or not at all.
R snowfall or heavy rain may lead to a parking
space being measured inaccurately.
R pay attention to the PARKTRONIC
( Y page 173) warning messages during the
parking procedure.
R you can intervene in the steering procedure
to correct it at any time. Active Parking
Assist will then be canceled.
R when transporting a load which protrudes
from your vehicle, you should not use
Active Parking Assist.
R never use Active Parking Assist when snow
chains or an emergency spare wheel are
mounted.
R make sure that the tire pressures are
always correct. This has a direct influence
on the parking characteristics of the
vehicle.
R the way your vehicle is positioned in the
parking space after parking is dependent
on various factors. These include the
position and shape of the vehicles parked
in front and behind it and the conditions of
the location. In some cases, Active Parking
Assist may guide you too far into a parking
space, or not far enough into it. In some
cases, it may also lead you across or onto
the curb. If necessary, you should abort the
parking procedure with Active Parking
Assist.
R you can also engage forward gear
prematurely. The vehicle redirects and
does not drive as far into the parking space.
Should the gear change occur too soon to
achieve a sensible parking position, the
parking procedure will be aborted.
! If unavoidable, you should drive over
obstacles such as curbs slowly and not at
a sharp angle. Otherwise, you may damage
the wheels or tires.
Detecting a parking space
Active Parking Assist is switched on
automatically when driving forwards. The
system is operational at speeds of up to
approximately 22 mph (35 km/h). While in
operation, the system independently locates
176Driving systemsDriving and parking

and measures parking spaces on both sides
of the vehicle. When driving at speeds below
19 mph (30 km/h), you will see the parking
symbol as a status indicator in the instrument
cluster. By default, Active Parking Assist only
displays parking spaces on the front-
passenger side. Parking spaces on the
driver's side are displayed as soon as the turn
signal on the driver's side is activated. If you
wish to park in a space on the driver's side,
the indicator on the driver's side must remain
on. This must remain switched on until you
acknowledge the use of Active Parking Assist
by pressing the a button on the
multifunction steering wheel.
When a parking space has been detected, an
arrow towards the right or the left also
appears.
Detected parking space (example)
:Detected parking space on the left;Parking symbol=Detected parking space on the right
Active Parking Assist will only detect parking
spaces:
R that are parallel to the direction of travel
R at least 59 in (1.5 m) wide
R at least 51 in (1.3 m) longer than your
vehicle
A parking space will be displayed to you as
you drive by until you are approximately 50 ft
(15 m) away from it.
Parking
GWARNING
PARKTRONIC and Active Parking Assist are
merely parking aids and may not detect all
obstacles. They do not relieve you of the
responsibility of paying attention.
You are always responsible for safety and
must continue to pay attention to your
immediate surroundings when parking and
maneuvering. You could otherwise endanger
yourself and others.XStop the vehicle when the parking space
symbol shows the desired parking space in
the instrument cluster.XShift the transmission to position R.
The Start Park Assist? Yes: OK No:
% message appears in the multifunction
display.XTo cancel the procedure: press the
% button on the multifunction steering
wheel or pull away.
or
XTo park using Active Parking Assist:
press the a button on the multifunction
steering wheel.
The Park Assist Active Accelerate
and Brake Observe Surroundings
message appears in the multifunction
display.GWARNING
When parking, you need to make sure that no
obstacles are located in the vicinity of the
vehicle during the entire operation. Active
Parking Assist does not relieve you of the
responsibility of paying attention. It merely
aids you by intervening actively in the
steering.
To stop the vehicle or to avoid an accident,
you need to apply the brakes yourself.
XLet go of the multifunction steering wheel.XBack up the vehicle, being ready to brake
at all times. Do not exceed a speed of
approximately 5 mph (10 km/h) while
backing up; Active Parking Assist will
otherwise be canceled.
i In tight parking spaces, you will achieve
the best parking results by backing up as
Driving systems177Driving and parkingZ

far as possible. When doing so, also
observe the PARKTRONIC messages.XStop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
Maneuvering may be required in tight
parking spaces.
The Park Assist Active Select D
Observe Surroundings message appears
in the multifunction display.
XShift the transmission to position D while
the vehicle is stationary.
Active Parking Assist immediately steers in
the other direction.
The Park Assist Active Accelerate
and Brake Observe Surroundings
message appears in the multifunction
display.
i You will achieve the best parking results
by waiting for the steering procedure to
complete before moving forwards.
XDrive forwards and be ready to brake at all
times.XStop as soon as PARKTRONIC sounds the
continuous warning tone, if not before.
The Park Assist Active Select R
Observe Surroundings message appears
in the multifunction display.
XFurther transmission shifts may be
necessary.
As soon as the parking procedure is
complete, the Park Assist Disabled
message appears in the multifunction
display. PARKTRONIC continues to be
available.
XManeuver if necessary.XAlways observe the warning messages
displayed by PARKTRONIC ( Y page 173).
Canceling Active Parking Assist
You can cancel Active Parking Assist at any
time.
XStop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at
once. The Park Assist Canceled
message appears in the multifunction
display.
or
XPress the PARKTRONIC button on the
center console ( Y page 173).
PARKTRONIC is switched off and Active
Parking Assist is immediately canceled.
The Park Assist Canceled message
appears in the multifunction display.
Active Parking Assist is canceled
automatically if:
R the transmission is shifted too early.
R parking using Active Parking Assist is no
longer possible.
R you are driving faster than 6 mph
(10 km/h).
R a wheel spins, ESP ®
intervenes or fails. The
ä warning lamp lights up in the
instrument cluster.
A warning tone sounds. The parking space
symbol disappears and the Park Assist
Canceled message appears in the
multifunction display.
When Active Parking Assist is canceled, you
must steer again yourself.
Rear view camera
Important safety notes
The rear view camera is an optical parking aid.
It shows the area behind your vehicle in the
COMAND display.
GWARNING
Make sure that no persons or animals are in
the maneuvering range. Otherwise, they
could be injured.
The rear view camera is located in the handle
strip of the trunk lid.
178Driving systemsDriving and parking

ATTENTION ASSIST
Important safety notes
ATTENTION ASSIST helps you during long,
monotonous journeys such as on freeways
and interstate highways. It is active in the
range between 50 mph (80 km/h) and
112 mph (180 km/h).
If ATTENTION ASSIST detects typical
indicators of fatigue or increasing lapses in
concentration on the part of the driver, it
suggests you take a break.
GWARNING
ATTENTION ASSIST is only an aid and may
detect your tiredness or lapses in
concentration too late or not at all. It is not a
substitute for a well-rested and attentive
driver.
Fatigue may cause you to recognize
hazardous situations too late, misjudge a
situation or react more slowly. For this
reason, make sure you feel rested before you
begin driving and during your journey. Make
sure that you take regular breaks in time,
particularly on long journeys. Otherwise, you
may fail to recognize dangers in time, cause
an accident and injure yourself and others.
ATTENTION ASSIST assesses your level of
fatigue or lapses in concentration by taking
the following criteria into account:
R your personal driving style, e.g. steering
characteristics
R driving conditions, e.g. time, driving time
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or
not occur at all:
R if the road condition is poor, e.g. if the
surface is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you predominantly drive at speeds under
50 mph (80 km/h) or over 112 mph
(180 km/h)
R if you are currently operating or making a
call using COMAND
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
Warning and display messages in the
multifunction displayXActivate ATTENTION ASSIST using the on-
board computer ( Y page 207).
Symbol : appears in the multifunction
display.
If ATTENTION ASSIST is active, you will be
warned no sooner than 20 minutes after your
journey has begun. You will then hear an
intermittent warning tone twice, and the
Attention Assist: Drowsiness
detected message appears in the
multifunction display.
XIf necessary, take a break.XPress a to confirm the message.
On long journeys, take regular breaks in good
time to allow yourself to rest properly. If you
do not take a break and ATTENTION ASSIST
still detects typical indicators of fatigue or
increasing lapses in concentration, you will be
warned again after 15 minutes at the earliest.
ATTENTION ASSIST is reset when you
continue your journey and starts assessing
your tiredness again if:
R you switch off the engine.
R you take off your seat belt and open the
driver's door, e.g. for a change of drivers or
to take a break.
180Driving systemsDriving and parking

The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to
insufficient illumination of the road, or due
to snow, rain, fog or spray.
R there is glare, e.g. from oncoming traffic,
the sun, or reflection from other vehicles.
R the windshield is dirty, fogged up or
covered, for instance by a sticker, in the
vicinity of the camera.
R several or no lane markings for a single lane
are present.
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow.
R the distance to the vehicle in front is too
small and the lane markings thus cannot be
detected.
R the lane markings on the road are unclear,
e.g. near roadworks.
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge.
R the road is narrow and winding.
Lane Keeping Assist cannot detect road and
traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, 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.
A warning can be given when a front wheel
passes over a lane marking. It will warn you
by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
In order that you are warned only when
necessary and in good time if you cross the
lane marking, the system recognizes certain
conditions and warns you accordingly.The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a
freeway.
R the system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.
No warning vibration occurs if:
R you clearly and actively steer, brake or
accelerate.
R you cut the corner on a sharp bend.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you switch on the turn signals. In this event,
the warnings are suppressed for a certain
period of time.
Switching on Lane Keeping AssistXActivate Lane Keeping Assist using the on-
board computer ( Y page 207).
Symbol : appears in the multifunction
display.
If your speed exceeds 40 mph (60 km/h)
and lane markings are detected,
symbol : is shown in green. Lane Keeping
Assist is ready for use.
Active Driving Assistance package
General information
The Active Driving Assistance package
consists of DISTRONIC PLUS ( Y page 157),
Active Blind Spot Assist ( Y page 188) and
Active Lane Keeping Assist ( Y page 191).
Driving systems187Driving and parkingZ

Active Blind Spot Assist
Important safety notes
Active Blind Spot Assist uses a radar sensor
system to monitor the side areas of your
vehicle which are in back of the driver. A
warning display in the exterior mirrors draws
your attention to detected vehicles in the
monitored area. If you then indicate a turn
towards that side before changing lanes, you
will also receive visual and audible collision
warnings. If a risk of lateral collision is
detected, corrective braking may help you
avoid a collision. To support the course-
correcting brake application, Active Blind
Spot Assist also uses the forward-facing radar
sensor system. Active Blind Spot Assist
supports you from speeds of approximately
20 mph (30 km/h).
GWARNING
Active Blind Spot Assist is only an aid, and
may detect vehicles/obstacles incorrectly or
not at all.
The system may be impaired or may not
function if:
R there is poor visibility, e.g. due to snow,
rain, fog or spray.
R the rear and/or front sensors are dirty.
Active Blind Spot Assist may not detect
narrow vehicles, such as motorcycles or
bicycles, or may only detect them too late. It
cannot detect vehicles that are overtaken at
a small distance and then enter the blind spot
area.
Active Blind Spot Assist cannot detect road
and traffic conditions. It is not a substitute for
attentive driving. You are responsible for the
vehicle's speed, 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.
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.
For Active Blind Spot Assist to assist you
when driving, the radar sensor system must
be activated ( Y page 211) and operational.
Monitoring area
Active Blind Spot Assist monitors the area
shown in the figure up to 10 ft (3 m) behind
and immediately adjacent to your vehicle. For
this purpose, Active Blind Spot Assist uses
radar sensors in the rear bumper.GWARNING
Active Blind Spot Assist monitors certain
areas in the immediate vicinity of your vehicle.
Vehicles that approach and drive past at high
speeds are not detected. No visual nor
audible warnings are emitted and the system
does not brake the vehicle to correct your
course.
188Driving systemsDriving and parking