2014 MERCEDES-BENZ CLA-Class brake sensor

Useful information
i This Operator's manual describes all
models and all standard and optional equip- ment of your vehicle available at the time of
publication of the Operator's manual.
Country-specific differences are possible.
Please note that your vehicle may not be
equipped with all features described. This
also applies to safety-related systems and
functions.
i Read the information on qualified special-
ist workshops (Y page 26). Notes on breaking-in a new vehicle
Important safety notes
The sensor system of some driving and driv-
ing safety systems adjusts automatically
while a certain distance is being driven after
the vehicle has been delivered or after
repairs. Full system effectiveness is not
reached until the end of this teach-in proce-
dure.
New and replaced brake pads and discs only
reach their optimum braking effect after sev-
eral hundred kilometers of driving. Compen-
sate for this by applying greater force to the
brake pedal. The first 1000 miles (1500 km)
The more you look after the engine when it is
new, the more satisfied you will be with its
performance in the future.
R You should therefore drive at varying vehi-
cle and engine speeds for the first
1000 miles (1500 km).
R Avoid heavy loads, e.g. driving at full throt-
tle, during this period.
R Change gear in good time, before the tach-
ometer needle is 00C3of the way to the red
area of the tachometer. R
Do not manually shift to a lower gear to
brake the vehicle.
R Try to avoid depressing the accelerator
pedal beyond the point of resistance (kick-
down).
R Ideally, for the first 1000 miles (1500 km),
drive in program E.
After 1,000 miles (1,500 km), you can
increase the engine speed gradually and bring the vehicle to full speed.
Additional breaking-in notes for AMG vehi-
cles:
R Do not drive faster than 85 mph
(140 km/h) for the first 1,000 miles
(1,500 km).
R Only allow the engine to reach a maximum
engine speed of 4,500 rpm briefly.
R Change gear in good time.
i You should also observe these notes on
breaking-in if the engine or parts of the
drive train on your vehicle have been
replaced.
i Always observe the respective speed lim-
its. Driving
Important safety notes
G
WARNING
Objects in the driver's footwell can restrict the pedal travel or obstruct a depressed pedal.
The operating and road safety of the vehicle is
jeopardized. There is a risk of an accident.
Make sure that all objects in the vehicle are
stowed correctly, and that they cannot enter
the driver's footwell. Install the floormats
securely and as specified in order to ensure
sufficient clearance for the pedals. Do not use loose floormats and do not place floormats on
top of one another. 140
DrivingDriving and parking

If cruise control is deactivated, you will hear a
warning tone. You will see the Cruise Con‐
Cruise Con‐
trol Off
trol Off message in the multifunction dis-
play for approximately five seconds.
i When you switch off the engine, the last
speed stored is cleared. DISTRONIC PLUS
General notes DISTRONIC PLUS regulates the speed and
automatically helps you maintain the dis-
tance to the vehicle detected in front. Vehi-
cles are detected with the aid of the radar
sensor system. DISTRONIC PLUS brakes
automatically so that the set speed is not
exceeded.
Change into a lower gear in good time on long and steep downhill gradients. This is espe-
cially important if the vehicle is laden. By
doing so, you will make use of the braking
effect of the engine. This relieves the load on
the brake system and prevents the brakes
from overheating and wearing too quickly.
If DISTRONIC PLUS detects that there is a risk
of a collision, you will be warned visually and acoustically. DISTRONIC PLUS cannot pre-
vent a collision without your intervention. An
intermittent warning tone will then sound and
the distance warning lamp will light up in the instrument cluster. Brake immediately in
order to increase the distance to the vehicle
in front or take evasive action provided it is
safe to do so.
DISTRONIC PLUS operates in range between 0 mph (0 km/h) and 120 mph (200 km/h).
Do not use DISTRONIC PLUS while driving on roads with steep gradients.
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
This device complies with RSS-210 of
Industry Canada. Operation is subject to
the following two conditions:
1. This device may not cause harmful inter- ference, 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 in any non-approved way.
Any unauthorized modification to this
device could void the user's authority to
operate the equipment.
Important safety notes G
WARNING
DISTRONIC PLUS does not react to:
R people or animals
R stationary obstacles on the road, e.g. stop-
ped or parked vehicles
R oncoming and crossing traffic
As a result, DISTRONIC PLUS may neither give
warnings nor intervene in such situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake. G
WARNING
DISTRONIC PLUS cannot always clearly iden- tify other road users and complex traffic sit-
uations.
In such cases, DISTRONIC PLUS may:
R give an unnecessary warning and then
brake the vehicle
R neither give a warning nor intervene
R accelerate unexpectedly
There is a risk of an accident.
Continue to drive carefully and be ready to
brake, in particular when warned to do so by
DISTRONIC PLUS. 168
Driving systemsDriving and parking

G
WARNING
DISTRONIC PLUS brakes your vehicle with up to 50% of the maximum possible deceleration.
If this braking force is insufficient, DISTRONIC
PLUS warns you visually and audibly. There is a risk of an accident.
In such cases, apply the brakes yourself and
try to take evasive action.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow- ing or other similar situations:
R when towing the vehicle
R in the car wash
If you fail to adapt your driving style, DIS-
TRONIC PLUS can neither reduce the risk of
accident nor override the laws of physics.
DISTRONIC PLUS cannot take into account
the road, traffic and weather conditions. DIS- TRONIC PLUS is only an aid. You are respon-
sible for the distance to the vehicle in front,
for vehicle speed, for braking in good time and for staying in your lane.
Do not use DISTRONIC PLUS:
R in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose
traction and the vehicle could then skid
R when there is poor visibility, e.g. due to fog,
heavy rain or snow
DISTRONIC PLUS may not detect narrow
vehicles driving in front, e.g. motorcycles, or
vehicles driving on a different line.
In particular, the detection of obstacles can
be impaired if:
R dirt on the sensors or anything else cover-
ing the sensors
R there is snow or heavy rain R
there is interference by other radar sources
R strong radar reflections, for example, in
parking garages
If DISTRONIC PLUS no longer detects a vehi- cle in front, DISTRONIC PLUS may unexpect-
edly accelerate the vehicle to the stored
speed.
This speed may:
R be too high if you are driving in a filter lane
or an exit lane
R be so high when driving in the right-hand
lane that you overtake vehicles in the left-
hand lane
R be so high when driving in the left-hand lane
that you overtake vehicles in the right-hand lane
If there is a change of drivers, advise the new
driver of the speed stored.
Cruise control lever 0043
To store the current speed or a higher
speed
0044 To store the current speed or a lower
speed
0087 To deactivate DISTRONIC PLUS
0085 To store the current speed or call up the
last stored speed
0083 To set the specified minimum distance Driving systems
169Driving and parking Z

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 30 mph
(Canada: 50 km/h). Drive program Sis acti-
vated. SPORT handling mode remains activa-
ted.
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
RACE START 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. 4MATIC
4MATIC ensures that all four wheels are per-
manently driven. Together with ESP ®
, it
improves the traction of your vehicle when-
ever 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.
! Never tow the vehicle with one axle
raised. This may damage the transfer case.
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.
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. PARK-
TRONIC does not detect such objects when they are in the immediate vicinity of the
vehicle. You could damage the vehicle or
the objects. 178
Driving systemsDriving and parking

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
PARKTRONIC is deactivated at speeds above
11 mph (18 km/h) . It is reactivated at lower
speeds.
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 0043
Sensors in the front bumper, left-hand
side (example) Side view
Top view
The sensors must be free from dirt, ice or
slush. They can otherwise not function cor-
rectly. Clean the sensors regularly, taking
care not to scratch or damage them
(Y page 291).
Front sensors Center Approx. 40 in (approx.
100 cm)
Corners Approx. 24 in (approx.
60 cm)
Rear sensors
Center Approx. 48 in (approx.
120 cm)
Corners Approx. 32 in (approx.
80 cm)
Minimum distance
Center Approx. 8 in (approx.
20 cm)
Corners Approx. 8 in (approx.
20 cm) Driving systems
179Driving and parking Z

Display messages
Possible causes/consequences and
0050
0050Solutions PRE-SAFE
PRE-SAFE
Functions Cur‐ Functions Cur‐
rently rently
Limited
Limited See
See
Operator's Manual
Operator's Manual Adaptive Brake Assist is temporarily inoperative. Possible causes
are:
R the front bumper is dirty.
R function is impaired due to heavy rain or snow.
R the radar sensor system is temporarily inoperative, e.g. due to
electromagnetic radiation emitted by nearby TV or radio sta-
tions or other sources of electromagnetic radiation.
R AMG vehicles: ESP ®
is deactivated.
R the system is outside the operating temperature range.
R the on-board voltage is too low.
When the causes stated above no longer apply, the display mes-
sage disappears.
Adaptive Brake Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 157).
X Clean the front bumper (Y page 291).
X Restart the engine.
X AMG vehicles: reactivate ESP ®
(Y page 69). PRE-SAFE PRE-SAFE
Functions Limited Functions Limited
See See
Operator's
Operator's Man‐
Man‐
ual
ual Adaptive Brake Assist is faulty. The distance warning signal may
also have failed.
X Visit a qualified specialist workshop. 0075
SRS Malfunction SRS Malfunction
Service Required Service Required There is a malfunction in the SRS (Supplemental Restraint Sys-
tem). The
0075warning lamp also lights up in the instrument clus-
ter.
G WARNING
The air bags or Emergency Tensioning Devices may either be trig- gered unintentionally or, in the event of an accident, may not be
triggered.
There is an increased risk of injury.
X Visit a qualified specialist workshop.
Further information on occupant safety (Y page 40).222
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
0050
0050Solutions 00D9
Off Off The HOLD function is deactivated. the vehicle is skidding.
A warning tone also sounds.
X Reactivate the HOLD function later (Y page 176). The HOLD function is deactivated. When the brake pedal is firmly
depressed, an activation condition is not fulfilled.
A warning tone also sounds.
X Check the activation conditions for the HOLD function
(Y page 176). Radar Radar
Sensors
Sensors Deac‐
Deac‐
tivated See Opera‐
tivated See Opera‐
tor's Manual tor's Manual The radar sensor system is deactivated.
X Switch on the radar sensor system (Y page 209).Lane Keeping
Lane Keeping
Assist Currently Assist Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual Lane Keeping Assist is deactivated and temporarily inoperative.
Possible causes are:
R the windshield in the camera's field of vision is dirty.
R visibility is impaired due to heavy rain, snow or fog.
R there are no lane markings for a longer period.
R the lane markings are worn, dark or covered, e.g. by dirt or snow.
When the causes stated above no longer apply, the display mes-
sage disappears.
Lane Keeping Assist is operational again.
If the display message does not disappear:
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Secure the vehicle against rolling away (Y page 157).
X Clean the windshield. Lane Keeping Lane Keeping
Assist Inoperative Assist Inoperative Lane Keeping Assist is faulty.
X Visit a qualified specialist workshop. Display
messages
233On-board computer and displays Z

Display messages
Possible causes/consequences and
0050
0050Solutions Warning Tire Mal‐
Warning Tire Mal‐
function function The tire pressure in one or more tires has dropped suddenly. The
wheel position is shown in the multifunction display.
G WARNING
If you drive with a flat tire, there is a risk of the following hazards: R a flat tire affects the ability to steer or brake the vehicle.
R you could lose control of the vehicle.
R continued driving with a flat tire will cause excessive heat build-
up and possibly a fire.
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 157).
X Check the tires and, if necessary, follow the instructions for a
flat tire (Y page 296). Tire Press. Moni‐ Tire Press. Moni‐
tor Currently tor Currently
Unavailable Unavailable Due to a source of radio interference, no signals can be received
from the wheel sensors. The tire pressure monitor is temporarily
malfunctioning.
X Drive on.
The tire pressure monitor restarts automatically as soon as the
problem has been solved. TirePress. Sen‐ TirePress. Sen‐
sor(s) Missing sor(s) Missing There is no signal from the tire pressure sensor of one or several
wheels. The pressure of the affected tire is not displayed in the
multifunction display.
X Have the faulty tire pressure sensor replaced at a qualified spe-
cialist workshop. Tire Pressure Mon‐ Tire Pressure Mon‐
itor Inoperative itor Inoperative
No Wheel Sensors No Wheel Sensors The wheels mounted do not have a suitable tire pressure sensor.
The tire pressure monitor is deactivated.
X Mount wheels with suitable tire pressure sensors.
The tire pressure monitor is activated automatically after driving
for a few minutes. Tire Press. Moni‐ Tire Press. Moni‐
tor Inoperative tor Inoperative The tire pressure monitor is faulty.
X Visit a qualified specialist workshop. 238
Display
messagesOn-board computer and displays