brake MERCEDES-BENZ CLA-Class 2015 C117 Repair Manual

DISTRONIC PLUS has not detected the vehi-
cle 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,
because of its narrow width. The distance to
the vehicle in front will be too short.
Obstructions and stationary vehicles DISTRONIC PLUS does not brake for obsta-
cles 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 detect vehicles that
are crossing your lane by mistake. Activating
DISTRONIC PLUS at traffic lights with cross-
ing traffic, for example, could cause your vehi-
cle 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.
Important safety notes G
WARNING
When leaving the vehicle, it can still roll away despite being braked by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply.
R the HOLD function has been deactivated by
pressing the accelerator pedal or the brake
pedal, e.g. by a vehicle occupant. 178
Driving systemsDriving an
d parking

R
the electrical system in the engine com-
partment, the battery or the fuses have
been tampered with.
R the battery is disconnected
There is a risk of an accident.
If you wish to exit the vehicle, always turn off
the HOLD function and secure the vehicle
against rolling away.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations.
To prevent damage to the vehicle, deacti-
vate DISTRONIC PLUS and the HOLD func-
tion in the following or other similar situa-
tions:
R when towing the vehicle
R in the car wash
Deactivating the HOLD function
(Y page 179).
Activation conditions You can activate the HOLD function if:
R the vehicle is stationary
R the engine is running or if it has been auto-
matically switched off by the ECO start/
stop function
R the driver's door is closed or your seat belt
is fastened
R the electric parking brake is released
R DISTRONIC PLUS is deactivated
R the transmission is in position D,Ror Non
vehicles with automatic transmission
Activating the HOLD function X
Make sure that the activation conditions
are met.
X Depress the brake pedal.
X Quickly depress the brake pedal further
until :appears in the multifunction dis-
play.
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.
Deactivating the HOLD function The HOLD function is deactivated automati-
cally if:
R you accelerate. On vehicles with automatic
transmission: only when the transmission
is in position Dor R.
R the transmission is in position Pon vehicles
with automatic transmission.
R you depress the brake pedal again with a
certain amount of pressure until :disap-
pears from the multifunction display.
R you activate DISTRONIC PLUS.
R you secure the vehicle using the electric
parking brake.
i After a time, the electric parking brake
secures the vehicle and relieves the service brake.
When the HOLD function is activated, the
transmission is shifted automatically to posi- tion Pif:
R the driver's seat belt is not fastened and the
driver's door is open.
R the engine is switched off, unless it is auto-
matically switched off by the ECO start/
stop function.
The electric parking brake secures the vehicle
automatically if the HOLD function is activa-
ted when the vehicle is stationary and:
R a system malfunction occurs.
R the power supply is not sufficient. Driving systems
179Driving and parking Z

RACE START (AMG vehicles)
Important safety notes RACE START enables optimal acceleration
from a standing start. The precondition for
this is a suitable high-grip road surface.
RACE START is intended solely for activation
on dedicated race circuits.
Conditions for activation You can activate RACE START if:
R the doors, hood and the trunk lid are
closed.
R the engine is running and the transmission,
all-wheel drive clutch and the engine are at
operating temperature.
R SPORT handling mode is activated
(Y page 68).
R the 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.
R drive program Mis selected (Y page 153).
Activating RACE START X
Depress the brake pedal with your left foot
and keep it depressed.
X Pull and hold both steering wheel paddle
shifters.
X The RACE START Confirm: Paddle UP
RACE START Confirm: Paddle UP
Cancel: Paddle DOWN
Cancel: Paddle DOWN message appears
in the multifunction display.
X Release both steering wheel paddle shift-
ers.
i If the activation conditions are no longer
fulfilled, RACE START is canceled. The
RACE START Not Possible See Opera‐
RACE START Not Possible See Opera‐
tor's Manual
tor's Manual message appears in the
multifunction display. X
To cancel: pull the left steering wheel pad-
dle shifter (Y page 154).
or
X To confirm: pull the right steering wheel
paddle shifter (Y page 154).
The RACE START Available Depress
RACE START Available Depress
gas pedal gas pedal message appears in the multi-
function display.
i If you do not depress the accelerator
pedal within a few seconds, RACE START is canceled. The multifunction display shows
the RACE START Canceled
RACE START Canceled message.
X Fully depress the accelerator pedal.
The engine speed is increased.
The RACE START Release brake to RACE START Release brake to
start
start message appears in the multifunc-
tion display.
i If you do not release the brake pedal
within a short time, RACE START will be
canceled. The multifunction display shows
the RACE START Canceled RACE START Canceled message.
X Take your foot off the brake, but keep the
accelerator pedal depressed.
The vehicle pulls away at maximum accel-
eration.
The RACE RACE START START Active
Active message appears
in the multifunction display.
RACE START is deactivated when the vehicle
reaches a speed of approximately 50 km/h.
Drive program Sis 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 condi-
tions are no longer fulfilled. The RACE RACESTART
START
Not Possible
Not Possible orRACE START Canceled
RACE START Canceled
message appears in the multifunction dis-
play.
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. 180
Driving systemsDriving and parking

4MATIC
! Never tow the vehicle with one axle
raised. This may damage the differential.
Damage of this sort is not covered by the
Mercedes-Benz Limited Warranty. All
wheels must remain either on the ground or be fully raised. Observe the instructions for
towing the vehicle with all wheels in full
contact with the ground.
4MATIC, together with ESP ®
, improves the
traction of your vehicle whenever a drive
wheel spins due to insufficient grip.
If you fail to adapt your driving style, 4MATIC
can neither reduce the risk of accident nor
override the laws of physics. 4MATIC cannot
take account of road, weather and traffic con- ditions. 4MATIC is only an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
If a drive wheel spins due to insufficient grip:
R Only depress the accelerator pedal as far as
necessary when pulling away.
R Accelerate less when driving.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires (M+S tires), with snow
chains if necessary. PARKTRONIC
Important safety notes PARKTRONIC is an electronic parking aid with
ultrasonic sensors. It monitors the area
around your vehicle using six sensors in the
front bumper and six sensors in the rear
bumper. PARKTRONIC indicates visually and
audibly the distance between your vehicle
and an object.
PARKTRONIC is only an aid. It is not a replace-
ment for your attention to your immediate
surroundings. You are always responsible for
safe maneuvering, parking and exiting a park- ing space. When maneuvering, parking or pulling out of a parking space, make sure that
there are no persons, animals or objects in
the area in which you are maneuvering.
! When parking, pay particular attention to
objects above or below the sensors, such
as flower pots or trailer drawbars.
PARKTRONIC does not detect such objects
when they are in the immediate vicinity of
the vehicle. You could damage the vehicle
or the objects.
The sensors may not detect snow and other
objects that absorb ultrasonic waves.
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.
PARKTRONIC is activated automatically when you:
R switch on the ignition
R shift the transmission to position D,Ror N
R release the electric parking brake
Range of the sensors General notes
PARKTRONIC does not take objects into con-
sideration that are:
R below the detection range, e.g. people, ani-
mals or objects.
R above the detection range, e.g. overhang-
ing loads, truck overhangs or loading
ramps. Driving systems
181Driving and parking Z

Problems with PARKTRONIC
Problem
Possible causes/consequences and
M
MSolutions Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is then
deactivated and the
indicator lamp on the
PARKTRONIC button
lights up. PARKTRONIC has malfunctioned and has switched off.
X If problems persist, have PARKTRONIC checked at a qualified
specialist workshop. Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is then
deactivated. The PARKTRONIC sensors are dirty or there is interference.
X Clean the PARKTRONIC sensors (Y page 295).
X Switch the ignition back on. The problem may be caused by an external source of radio or
ultrasound waves.
X See if PARKTRONIC functions in a different location. Active Parking Assist
General notes Active Parking Assist is an electronic parking
aid with ultrasound. It measures the road on
both sides of the vehicle. A parking symbol
indicates a suitable parking space. Active
steering intervention and brake application
can assist you during parking and when exit-
ing a parking space. You may also use
PARKTRONIC (Y page 181).
Important safety notes Active Parking Assist is merely an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking
and exiting a parking space. Make sure that
no persons, animals or objects are in the
maneuvering range.
When PARKTRONIC is switched off, Active
Parking Assist is also unavailable. G
WARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
result in a collision with another road user.
There is a risk of an accident.
Pay attention to other road users. Stop the
vehicle if necessary or cancel the Active Park- ing Assist parking procedure.
! 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.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
R where parking or stopping is prohibited
R in front of driveways or entrances and exits
R on unsuitable surfaces 184
Driving systemsDriving and parking

22 mph (35 km/h). While in operation, the
system independently locates and measures
parking spaces on both sides of the vehicle.
Active Parking Assist will only detect parking spaces:
R that are parallel or at right-angles to the
direction of travel
R that are parallel to the direction of travel
and at least 59 in (1.5 m) wide
R that are parallel to the direction of travel
and at least 39.5 in (1.0 m) longer than your
vehicle
R that are at right angles to the direction of
travel and at least 39.5 in (1.0 m) wider
than your vehicle
i Note that Active Parking Assist cannot
measure the length of a parking space if it
is at right angles to the direction of travel.
You will need to judge whether your vehicle will fit into the parking space.
When driving at speeds below 19 mph
(30 km/h), you will see parking symbol ;as
a status indicator in the instrument cluster.
When a parking space has been detected, an arrow towards the right or the left also
appears. By default, Active Parking Assist
only displays parking spaces on the front-
passenger side. Parking spaces on the driv-
er's side are displayed as soon as the turn
signal on the driver's side is activated. When
parking on the driver's side, this must remain
activated until you confirm the use of Active
Parking Assist by pressing the abutton on
the multifunction steering wheel. The system
automatically determines whether the park-
ing space is parallel or at right-angles to the
direction of travel.
A parking space is displayed while you are
driving past it, and until you are approx-
imately 50 ft (15 m) away from it. Pa
rking G
WARNING
If you leave the vehicle when it is only being
braked by Active Parking Assist it could roll
away if:
R there is a malfunction in the system or in
the voltage supply.
R the electrical system in the engine com-
partment, the battery or the fuses have
been tampered with.
R the battery is disconnected.
R the accelerator pedal has been depressed,
e.g. by a vehicle occupant.
There is a risk of an accident.
Before leaving the vehicle, always secure it
against rolling away.
i When PARKTRONIC detects obstacles,
Active Parking Assist brakes automatically
during the parking process. You are respon- sible for braking in good time.
X Stop the vehicle when the parking space
symbol shows the desired parking space in
the instrument cluster.
X Shift the transmission to position R.
The Start Park Assist? Start Park Assist? Yes: OK
Yes: OKNo:
No:
% message appears in the multifunction
display.
X To cancel the procedure: press the%
button on the multifunction steering wheel or pull away.
or
X To park using Active Parking Assist:
press the abutton on the multifunction
steering wheel.
The Park Assist Active Accelerate Park Assist Active Accelerate
and Brake
and Brake Observe Surroundings
Observe Surroundings mes-
sage appears in the multifunction display.
X Let go of the multifunction steering wheel.
X Back up the vehicle, being ready to brake at
all times. When backing up, drive at a speed below approximately 6 mph (10 km/h). 186
Driving systemsDriving an
d parking

Otherwise Active Parking Assist will be can-
celed.
Active Parking Assist brakes the vehicle to a standstill when the vehicle approaches
the rear border of the parking space.
Maneuvering may be required in tight park- ing spaces.
The Park Assist Active Select D
Park Assist Active Select D
Observe Observe Surroundings
Surroundings message appears in
the multifunction display.
X Shift the transmission to position Dwhile
the vehicle is stationary.
Active Parking Assist immediately steers in
the other direction.
The Park Assist Active Accelerate Park Assist Active Accelerate
and Brake
and Brake Observe Surroundings
Observe Surroundings mes-
sage appears in the multifunction display.
i You will achieve the best results by wait-
ing for the steering procedure to complete before pulling away.
X Drive forwards and be ready to brake at all
times.
Active Parking Assist brakes the vehicle to a standstill when the vehicle approaches
the front border of the parking space.
Maneuvering may be required in tight park-
ing spaces.
The Park Assist Active Select R
Park Assist Active Select R
Observe Observe Surroundings
Surroundings message appears in
the multifunction display.
As soon as the parking procedure is com-
plete, the Park
Park Assist Assist Switched
Switched Off
Offmes-
sage appears and a warning tone sounds. The vehicle is now parked.
The vehicle is kept stationary without the
driver having to depress the brake pedal. The
braking effect is canceled when you depress
the accelerator pedal.
Active Parking Assist no longer supports you
with steering interventions and brake appli-
cations. When Active Parking Assist is fin-
ished, you must steer and brake again your-
self. PARKTRONIC is still available. Parking tips:
R The way your vehicle is positioned in the
parking space after parking is dependent
on various factors. These include the posi-
tion and shape of the vehicles parked in
front and behind it and the conditions of the
location. It may be the case that Active
Parking Assist guides 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 can- cel the parking procedure with Active Park-ing Assist.
R You can also select preselect transmission
position D. The vehicle redirects and does
not drive as far into the parking space.
Should the transmission change take place too early, the parking procedure will be
canceled. A sensible parking position can
no longer be achieved from this position.
Exiting a parking space In order that Active Parking Assist can sup-
port you when you exit the parking space:
R you need to have parked using Active Park-
ing Assist.
R the border of the parking space must be
high enough at the front and the rear. A
curb is too small, for example.
R the border of the parking space must not be
too wide, as the position of the vehicle must
not exceed an angle of 45° to the starting
position as it is maneuvering into the park- ing space.
R a maneuvering distance of at least 3.3 ft
(1.0 m) must be available.
Active Parking Assist can only assist you with exiting a parking space if you have parked thevehicle parallel to the direction of travel using
Active Parking Assist.
i If PARKTRONIC detects obstacles, Active
Parking Assist brakes automatically whilst
the vehicle exits the parking space. You are
responsible for braking in good time. Driving systems
187Driving and parking Z

X
Start the engine.
X Release the electric parking brake.
X Switch on the turn signal in the direction
you are pulling away.
X Shift the transmission to position Dor R.
The Start Park Assist? Yes: OK No:
Start Park Assist? Yes: OK No:
message appears in the multifunction dis-
play %.
X To cancel the procedure: press the%
button on the multifunction steering wheel or pull away.
or
X To exit a parking space using Active
Parking Assist: press theabutton on
the multifunction steering wheel.
The Park Assist Active Accelerate
Park Assist Active Accelerate
and
and Brake Brake Observe
Observe Surroundings
Surroundings mes-
sage appears in the multifunction display.
X Let go of the multifunction steering wheel.
X Pull away, being ready to brake at all times.
Do not exceed a maximum speed of
approximately 6 mph (10 km/h) when exit-
ing a parking space. Otherwise Active Park- ing Assist will be canceled.
X Depending on the message or as required,
shift the transmission to position Dor R.
Active Parking Assist immediately steers in the other direction. The Park Assist
Park Assist
Active Accelerate and Brake
Active Accelerate and Brake
Observe Observe Surroundings
Surroundings message appears
in the multifunction display.
i You will achieve the best results by wait-
ing for the steering procedure to complete before pulling away.
If you back up after activation, the steeringwheel is moved to the straight-ahead posi-
tion.
X Drive forwards and back up as prompted by
the PARKTRONIC warning displays, several
times if necessary.
Once you have exited the parking space com- pletely, the steering wheel is moved to the
straight-ahead position. You hear a tone and
the Park Assist Finished
Park Assist Finished message
appears in the multifunction display. You will then have to steer and merge into traffic on
your own. PARKTRONIC is still available. You
can take over the steering, before the vehicle has exited the parking space completely. This
is useful, for example when you recognize
that it is already possible to pull out of the
parking space.
Canceling Active Parking Assist X
Stop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at
once. The Park Assist Canceled Park Assist Canceled mes-
sage appears in the multifunction display.
or X Press the PARKTRONIC button
(Y page 183).
PARKTRONIC is switched off and Active
Parking Assist is immediately canceled.
The Park Assist Canceled Park Assist Canceled message
appears in the multifunction display.
Active Parking Assist is canceled automati-
cally if: R the electric parking brake is engaged
R transmission position Pis selected
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
÷ warning lamp lights up in the instru-
ment cluster
A warning tone sounds. The parking symbol
disappears and the multifunction display
shows the Park Assist Canceled Park Assist Canceled mes-
sage.
When Active Parking Assist is canceled, you
must steer and brake again yourself.
If a system malfunction occurs, the vehicle is
braked to a standstill. To drive on, depress the accelerator again. 188
Driving systemsDriving and parking

Collision warning
If a vehicle is detected in the monitoring range
of Blind Spot Assist and you switch on the
corresponding turn signal, a double warning
tone sounds. Red warning lamp :flashes. If
the turn signal remains on, detected vehicles
are indicated by the flashing of red warning
lamp :. There are no further warning tones.
Switching on Blind Spot Assist
X Make sure that Blind Spot Assist is activa-
ted in the on-board computer
(Y page 211).
X Turn the SmartKey to position 2in the igni-
tion lock.
Warning lamps :in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Lane Keeping Assist General notes
Lane Keeping Assist monitors the area in
front of your vehicle with camera :, which is
mounted at the top of the windshield. Active
Lane Keeping Assist detects lane markings on
the road and can warn you before you leave
your lane unintentionally.
This function is available in the range between
40 mph and 120 mph (60 km/h and
200 km/h).
A warning may be given if a front wheel
passes over a lane marking. It will warn you by means of intermittent vibration in the steer-
ing wheel for up to 1.5 seconds. Important safety notes G
WARNING
Lane Keeping Assist may not always clearly
recognize lane markings.
In this case, Lane Keeping Assist may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay particular attention to the traffic
situation and stay in lane, in particular if
warned by Lane Keeping Assist. G
WARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There is a risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep-ing Assist.
If you fail to adapt your driving style, Lane
Keeping Assist can neither reduce the risk of
an accident nor override the laws of physics.
Lane Keeping Assist cannot take into account the road, traffic and weather conditions. Lane
Keeping Assist is merely an aid. You are
responsible for the distance to the vehicle in
front, for vehicle speed, for braking in good
time and for staying in your lane.
The Lane Keeping Assist does not keep the
vehicle in the lane.
The system may be impaired or may not func- tion if:
R there is poor visibility, e.g. due to insuffi-
cient illumination of the road, or due to
snow, rain, fog or spray
R there is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R there are no, several or unclear lane mark-
ings for a lane, e.g. in areas with road con-
struction work 196
Driving systemsDriving and parking

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 change quickly, e.g.
lanes branch off, cross one another or
merge
R the road is narrow and winding
R there are strong shadows cast on the road
Switching on Lane Keeping Assist
X Activate Lane Keeping Assist using the on-
board computer; to do so, select Standard
Standard
or Adaptive Adaptive (Ypage 211).
If you drive at speeds above 60 km/h and
lane markings are detected, the lane mark- ings in the assistance graphics display
(Y page 209) are shown in green.
When Standard
Standard is selected, no warning vibra-
tion occurs if:
R you have switched on the turn signals. In
this event, the warnings are suppressed for
a certain period of time.
R a driving safety system intervenes, such as
ABS, BAS or ESP ®
.
When Adaptive
Adaptive is selected, no warning vibra-
tion occurs if:
R you have switched on the turn signals. In
this event, the warnings are suppressed for a certain period of time.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when nec-
essary and in good time if you cross the lane marking, the system recognizes certain con-
ditions 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 high-
way.
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. Driving systems
197Driving and parking Z