brake sensor MERCEDES-BENZ B-CLASS HATCHBACK 2014 User Guide

Permanent SPEEDTRONIC
You can use the on-board computer to limit
the speed permanently to a value between
160 km/h(e.g. for driving on winter tyres) and the maximum speed (Y page 247).
Shortly before the stored speed is reached, it
appears in the multifunction display.
Permanent SPEEDTRONIC remains active
even if variable SPEEDTRONIC is deactivated.
You cannot exceed the stored limit speed
even if you depress the accelerator pedal
beyond the pressure point (kickdown). 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 to avoid exceeding the set
speed or to maintain the designated distance from the vehicle in front.
Change into a lower gear in good time on long
and steep downhill gradients. Take particular
note of this when driving a laden vehicle. 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. Without your intervention,
DISTRONIC PLUS cannot prevent a collision.
An intermittent warning tone will then sound
and the distance warning lamp will light up in the instrument cluster. Brake immediately to
increase the distance to the vehicle driving in
front, or take evasive action, provided it is
safe to do so.
DISTRONIC PLUS operates in the range
between 0 km/h and 200 km/h.
Do not use DISTRONIC PLUS while driving on roads with steep gradients. 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 rec-
ognise other road users and complex traffic
conditions.
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 or brake unexpectedly
There is a risk of an accident.
Continue to drive carefully and be prepared to
brake, particularly if DISTRONIC PLUS warns
you. G
WARNING
DISTRONIC PLUS brakes your vehicle with up to 50% of the maximum possible deceleration.
If this deceleration is not sufficient,
DISTRONIC PLUS alerts you with a visual and
acoustic warning. There is a risk of an acci-
dent.
Apply the brakes yourself in these situations
and try to take evasive action.
! When DISTRONIC PLUS or the HOLD
function is activated, the vehicle brakes
automatically in certain situations. Driving systems
193Driving and parking Z

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 implied 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 an 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 lane.
If a drive wheel spins due to insufficient grip:
R when pulling away, only depress the accel-
erator pedal as far as is necessary.
R accelerate less when driving.
i In wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tyres (M+S tyres), 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 substi-
tute for your attention to the immediate sur-
roundings. The responsibility for safe
manoeuvring and parking remains with you.
Make sure that there are no persons, animals or objects in range while manoeuvring and
parking.
! 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
objects which absorb ultrasonic sources.
Ultrasonic sources, such as an automatic
car wash, a lorry's compressed-air brakes
or a pneumatic drill, could cause
PARKTRONIC to malfunction.
PARKTRONIC may not function correctly on uneven terrain.
! Fold in the ball coupling if the trailer tow
hitch is not required. PARKTRONIC meas-
ures the minimum detection range to an
obstacle from the bumper, not the ball cou- pling.
PARKTRONIC is activated automatically when you:
R switch on the ignition
R shift to position D,Ror Non vehicles with
automatic transmission
R release the electric parking brake
PARKTRONIC is deactivated at speeds above
18 km/h. It is reactivated at lower speeds.
PARKTRONIC is deactivated for the rear area when you establish an electrical connection
between your vehicle and a trailer.
Range of the sensors General notes
PARKTRONIC does not take into account
obstacles located:
R below the detection range, e.g. persons,
animals or objects
R above the detection range, e.g. overhang-
ing loads, tail sections or loading ramps of
goods vehicles Driving systems
203Driving 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 been deactivated.
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 328).
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 203).
i The active braking application is only
available on vehicles with automatic trans-
mission.
Important safety notes Active Parking Assist is only an aid. It is not a
substitute for your attention to the immediate
surroundings. The responsibility for safe
manoeuvring and parking remains with you. Make sure that no persons, animals or
objects are in the manoeuvring range.
When PARKTRONIC is deactivated, 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
cause you to collide with other road users.
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 kerbs slowly and not at a
sharp angle. Otherwise, you may damage
the wheels or tyres. 206
Driving systemsDriving and parking

Display messages
Possible causes/consequences and
M
MSolutions J
Check brake fluid Check brake fluid
level level There is insufficient brake fluid in the brake fluid reservoir.
In addition, the red Jwarning lamp lights up in the instrument
cluster and a warning tone sounds.
G WARNING
Braking efficiency may be impaired.
There is a risk of an accident. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 181).
X Consult a qualified specialist workshop.
X Do not top up the brake fluid. This does not correct the fault. #
Check brake pad Check brake pad
wear wear The brake pads/linings have reached their wear limit.
X Visit a qualified specialist workshop. G
Inoperative
Inoperative One or more main features of the Mercedes-Benz Connect system
are malfunctioning.
X Have the system checked at a qualified specialist workshop. Collision Preven‐
Collision Preven‐
tion Assist Plus tion Assist Plus
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual COLLISION PREVENTION ASSIST PLUS is temporarily inoperative.
Possible causes:
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 the system is outside the operating temperature range
R the on-board voltage is too low
Once the causes listed above no longer apply, the display message goes out.
COLLISION PREVENTION ASSIST PLUS 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 181).
X Restart the engine. Collision Preven‐ Collision Preven‐
tion Assist Plus tion Assist Plus
inoperative inoperative COLLISION PREVENTION ASSIST PLUS is temporarily inoperative
due to a malfunction. Adaptive Brake Assist may also have failed.
X Visit a qualified specialist workshop. Display
messages
259On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions Traffic Sign
Traffic Sign
Assist currently Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual Traffic Sign Assist is temporarily inoperative.
Possible causes:
R the windscreen is dirty in the camera's field of vision
R visibility is impaired due to heavy rain, snow or fog
X Clean the windscreen.
If the system detects that the camera is fully operational, the dis-
play message disappears.
Traffic Sign Assist is operational again. Traffic Sign Traffic Sign
Assist inoperative Assist inoperative Traffic Sign Assist is faulty.
X Visit a qualified specialist workshop. DISTRONIC PLUS off
DISTRONIC PLUS off DISTRONIC PLUS has been deactivated (Y
page 193).
If it was not deactivated by the driver, a warning tone also sounds. DISTRONIC PLUS
DISTRONIC PLUS
available again available again DISTRONIC PLUS is operational again after having been tempo-
rarily unavailable. You can now reactivate DISTRONIC PLUS
(Y
page 193). DISTRONIC DISTRONIC
PLUS
PLUScur‐
cur‐
rently
rently unavailable
unavailable
See Owner's Manual
See Owner's Manual DISTRONIC PLUS is temporarily inoperative.
Possible causes:
R the 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 the system is outside the operating temperature range
R the on-board voltage is too low
A warning tone also sounds.
Once the causes listed above no longer apply, the display message
goes out.
DISTRONIC PLUS 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 181).
X Restart the engine. DISTRONIC PLUS DISTRONIC PLUS
inoperative inoperative DISTRONIC PLUS is faulty. Adaptive Brake Assist may also have
failed.
A warning tone also sounds.
X Visit a qualified specialist workshop. 274
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Tyre press. moni‐
Tyre press. moni‐
tor currently tor currently
unavailable unavailable No signals can be received from the tyre pressure sensors due to
strong RF interference. The tyre pressure monitor is temporarily
malfunctioning.
X Drive on.
The tyre pressure monitor restarts automatically as soon as the
cause has been rectified. Wheel sensor(s) Wheel sensor(s)
missing missing There is no signal from the tyre pressure sensor of one or several
wheels. The pressure of the affected tyre is not displayed in the
multifunction display.
X Have the faulty tyre pressure sensor replaced at a qualified spe-
cialist workshop. Tyre press. moni‐ Tyre press. moni‐
tor tor
inoperative
inoperative No
No
wheel sensors
wheel sensors The wheels fitted do not have suitable tyre pressure sensors. The
tyre pressure monitor is deactivated.
X Fit wheels with suitable tyre pressure sensors.
The tyre pressure monitor is activated automatically after driv-
ing for a few minutes. Tyre press. moni‐ Tyre press. moni‐
tor inoperative tor inoperative The tyre pressure monitor is faulty.
X Visit a qualified specialist workshop. Vehicle
Display messages
Possible causes/consequences and
M
MSolutions Depress brake to
Depress brake to
start engine start engine You have attempted to start the engine with the transmission in
position
Nwithout depressing the brake pedal.
X Depress the brake pedal. To shift out of P To shift out of P
or N, depress or N, depress
brake and start brake and start
engine engine You have attempted to shift the selector lever to position
Ror D
without starting the engine.
X Start the engine.
X Depress the brake pedal.
i It is only possible to move the selector lever from position
Pto
the desired position if you depress the brake pedal. Only then
can the parking lock be deactivated. If you do not depress the
brake pedal, the DIRECT SELECT lever can still be moved but the parking lock remains engaged.
i At transmission fluid temperatures below
Ò20 † you can only
shift out of position Pinto another transmission position when
the engine is running. 278
Display
messagesOn-board computer and displays