2017 MERCEDES-BENZ B-Class parking sensors

Active Brake Assist
General information i
Observe the "Important safety notes" sec-
tion (Y page 58).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and braking assistance appropriate to the
situation.
Active Brake Assist can help you to minimize the risk of a collision with the vehicle traveling in
front or reduce the effects of such a collision.
If Active Brake Assist detects that there is a risk
of collision, you will be warned visually and
acoustically. If you do not react to the visual and audible collision warning, autonomous braking
can be initiated in critical situations. If you apply
the brake yourself in a critical situation, Adap-
tive Brake Assist supports you with braking
assistance appropriate to the situation.
Important safety notes Detection of hazardous situations can be par-
ticularly impaired by:
R there is dirt on the sensors or anything else
covering the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are strong radar reflections, for exam-
ple in parking garages
R a narrow vehicle is traveling in front, e.g. a
motorbike
R a vehicle is traveling in front on a different line
R new vehicles or after servicing is carried out
on the Active Brake Assist system
Observe the important safety notes in the
"Breaking-in notes" section (Y page 108).
Following damage to the front end of the vehicle, have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at low
speeds where no visible damage to the front of
the vehicle is apparent.
Activating/deactivating Active Brake Assist is active after every ignition
cycle.
You can activate or deactivate Active Brake
Assist (Y page 162) in the on-board computer. When deactivated, the distance warning func-
tion and the autonomous braking function are
also deactivated.
If Active Brake Assist is deactivated, the 00D4
symbol appears in the assistance graphic dis-
play.
Distance warning function General information
The distance warning function can help you to
minimize the risk of a front-end collision with a
vehicle ahead or reduce the effects of such a
collision. If the distance warning function
detects that there is a risk of a collision, you will
be warned visually and acoustically.
Important safety notesi Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 58). G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
Thus, the distance warning function cannot
provide a warning in all critical situations.
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and be ready to brake. G
WARNING
The distance warning function cannot always
clearly identify objects and complex traffic
situations.
In such cases, the distance warning function
may:
R give an unnecessary warning
R not give a warning
There is a risk of an accident.
Always pay careful attention to the traffic sit-
uation and do not rely solely on the distance
warning function. 60
Driving safety systemsSafety

The braking performance of the electric motor
using recuperative braking is, in some operating modes, either reduced or not effective:
R when the condition of charge of the high-volt-
age battery increases
R if the high-voltage battery is not yet at a nor-
mal operating temperature
R when driving close to the vehicle's maximum
design speed
R when the vehicle is almost stationary
R in transmission position N
R during and after ESP stability control
If you do not make an additional effort to apply
the brake yourself, the braking effect may not be sufficient. If necessary, counteract the reduced
regenerative braking effect by applying the
brake yourself.
Radar-based recuperation The vehicle uses the Active Brake Assist sensors
during radar-based recuperation ( DAUTO
). The
sensors detect the distance to the vehicle ahead
and its speed. The intensity of recuperation is
then automatically adjusted to the current traf-
fic situation.
The range can then be increased by storing
energy efficiently. Adjustment is infinitely vari-
able from overrun mode (no recuperation) to
maximum recuperation.
Maintain sufficient distance to the vehicle in
front. Mercedes-Benz recommends that you
activate Active Brake Assist as a visual and
acoustic aid.
Examples of radar-based recuperation:
R Approaching a slower vehicle, a decelerating
vehicle or when following a vehicle downhill.
Your vehicle decelerates slightly and increa-
ses recuperation.
R Driving when no vehicle is detected in front or
when a vehicle is detected in the far distance or an accelerating vehicle is detected. Your
vehicle switches to overrun mode at higher
speeds.
R Driving on a steep downhill slope. Accelera-
tion downhill is reduced and recuperation is
increased. This is comparable with shifting
down when driving downhill. X
To activate radar-based recuperation: pull
steering wheel paddle shifter 0043or0044
towards you and hold for about one second.
X To deactivate radar-based recuperation:
briefly pull steering wheel paddle shifter 0043
or 0044 towards you.
If you change between radar-based and manual
recuperation, the following levels are activated
depending on the selection via the steering
wheel paddle shifters: 0043
Steering wheel
paddle shifter - selects
D-
(maximum
recuperation) 0044
Steering wheel
paddle shifter + selects
D+
(overrun) In particular, the function of the radar sensors
can be impaired in the case of:
R there is dirt on the sensors or anything else
covering the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are strong radar reflections, for exam-
ple in parking garages
R a narrow vehicle is traveling in front, e.g. a
motorbike
R a vehicle is traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the vehicle,
have the radar sensor settings and operation
checked at a qualified specialist workshop
immediately. This also applies to collisions at
slow speeds where there is no visible damage to the front of the vehicle.
If the radar sensors are not available, the system switches automatically to level Dwith moderate
recuperation. Have the radar sensors checked
at a qualified specialist workshop immediately.
Automatic adjustment of recuperation
on downhill gradients The vehicle can detect steep downhill gradients.
To reduce acceleration downhill and to charge
the high-voltage battery, recuperation is
increased steplessly. This is comparable to the
engine brake in a combustion engine when you
downshift a gear on a downhill gradient.
Automatic adjustment of recuperation on down-
hill gradients is available in level DAUTO
or on 116
TransmissionDriving and parking

vehicles without steering wheel paddle shifters
in level D.
Intelligent recuperation During radar-based recuperation (
DAUTO
), the
vehicle uses the map and camera data of Traffic
Sign Assist in addition to the Active Brake Assist
sensors. The rate of recuperation is then auto-
matically adjusted to the current traffic situa-
tion, taking the current and future maximum
speed into account. High-voltage battery
Important safety notes
G
DANGER
The vehicle's high-voltage electrical system is under high voltage. If you modify components
in the vehicle's high-voltage electrical system
or touch damaged components, you may be
electrocuted. The components in the vehi-
cle's high-voltage electrical system may be
damaged in an accident, although the damage is not visible. There is a risk of fatal injury.
Following an accident, do not touch any high- voltage components and never modify the
vehicle's high-voltage electrical system. Have
the vehicle towed away after an accident and
the vehicle's high-voltage electrical system
checked by a qualified specialist workshop. G
WARNING
In the event of a vehicle fire, the internal pres- sure of the high-voltage battery can exceed a
critical value. In this case flammable gas
escapes through a ventilation valve on the
underbody. The gas can ignite. There is a risk of injury.
Leave the danger zone immediately. Secure
the danger area at a suitable distance, whilst
observing legal requirements. G
DANGER
Connecting the charging cable to the mains
supply via incorrectly installed mains sockets or by means of adapters, extension cables or similar could cause a fire or an electric shock.
There is a risk of fatal injury.
To avoid hazardous situations, observe the
following:
R Only connect the charging cable to mains
sockets:
- which have been properly installed and
- which have been inspected by a qualified
electrician
R For safety reasons, only use the charging
cables supplied with the vehicle, or charg-
ing cables which have been approved for
use with this vehicle.
R Never use a damaged charging cable.
R Do not use:
- extension cables
- extension reels
- multiple sockets
R Never use socket adapters to connect the
charging cable to the mains socket. The
only exception being if the adapter has
been tested and approved by the manufac-
turer for charging the high-voltage battery
of an electric vehicle.
R Observe the safety notes in the operating
instructions for the socket adapter. G
DANGER
Connecting the charging cable to the wallbox via an incorrectly installed wallbox or adapter,
extension cable or similar could cause a fire or an electric shock. There is a risk of fatal injury.
To avoid hazardous situations, observe the
following:
R Only connect the charging cable to a wall-
box that:
- is installed correctly and
- has been inspected by a qualified elec-
trician
R For safety reasons, only use charging
cables that have been tested and approved by the manufacturer for charging the high-
voltage battery in an electric vehicle. High-voltage battery
117Driving and parking
Z

The electric parking brake secures the vehicle
automatically if the HOLD function is activated
and:
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.
R a system malfunction occurs.
R the power supply is insufficient.
The Brake Immediately Brake Immediately message may also
appear in the multifunction display.
X Immediately depress the brake firmly until the
warning message in the multifunction display goes out.
The HOLD function is deactivated. The horn
sounds at regular intervals if you have switched
off the engine, released the seat belt and
opened the driver's door with the HOLD function activated. The sounding of the horn alerts you to
the fact that the HOLD function is still activated.
If you attempt to lock the vehicle, the tone
becomes louder. The vehicle cannot be locked
until you have deactivated the HOLD function.
i After switching off the engine, it can only be
started again once you have deactivated the
HOLD function. Parking Assist PARKTRONIC
Important safety notes Parking Assist PARKTRONIC is an electronic
parking aid with ultrasound. It monitors the area
around your vehicle using six sensors in the
front bumper and six sensors in the rear
bumper. Parking Assist PARKTRONIC visually
and audibly indicates the distance between your
vehicle and an object.
Parking Assist PARKTRONIC is only 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. 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 maneuver-
ing.
! When parking, pay particular attention to
objects above or below the sensors, such as
flower pots or trailer drawbars. Parking Assist 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 of a truck or
a pneumatic drill could cause Parking Assist
PARKTRONIC to malfunction.
Parking Assist PARKTRONIC may not function
correctly on uneven terrain.
Parking Assist PARKTRONIC is activated auto-
matically when you: R switch on the ignition
R shift the transmission to position D,Ror N
R shift the transmission to position D,Ror N
R release the electric parking brake
Parking Assist PARKTRONIC is deactivated at
speeds above 11 mph (18 km/h) . It is reactiva-
ted at lower speeds.
Range of the sensors General notes
Parking Assist PARKTRONIC does not take into
account obstacles located:
R below the detection range, e.g. people, ani-
mals or objects.
R above the detection range, e.g. overhanging
loads, tail sections or loading ramps of goods
vehicles. 0043
Sensors in the front bumper, left-hand side
(example)
The sensors must be free from dirt, ice or slush. They can otherwise not function correctly. Clean
the sensors regularly, taking care not to scratch
or damage them (Y page 237). Driving systems
139Driving and parking Z

Range
0043
Detection range of front sensors
0044 Detection range of rear sensors
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. 6 in (approx. 15 cm)
If there is an obstacle within this range, the rel-
evant warning displays light up and a warning
tone sounds. If the distance falls below the min- imum, the distance may no longer be shown. Warning displays
0043
Segments on the left-hand side of the vehi-
cle
0044 Segments on the right-hand side of the vehi-
cle
0087 Segments showing operational readiness
The warning displays show the distance
between the sensors and the obstacle. The
warning display for the front area is located on
the dashboard above the center air vents. The
warning display for the rear area is located on
the headliner in the rear compartment.
The warning display for each side of the vehicle
is divided into five yellow and two red segments.
Parking Assist PARKTRONIC is operational if yel-
low segments showing operational readiness 0087
light up.
The transmission position of the automatic
transmission and the direction in which the vehi-
cle is rolling determine which warning display is active when the engine is running. Transmission posi-
tion Warning display
D
Front area activated
R,
Nor the vehicle is
rolling backwards Rear and front areas
activated
P
No areas activated
One or more segments light up as the vehicle
approaches an obstacle, depending on the vehi-
cle's distance from the obstacle.
From the:
R sixth segment onwards, you will hear an inter-
mittent warning tone for approximately two
seconds.
R seventh segment onwards, you will hear a
warning tone for approximately two seconds. 140
Driving systemsDriving and parking

This indicates that you have now reached the
minimum distance.
Deactivating or activating Parking
Assist PARKTRONIC 0043
Indicator lamp
0044 Deactivates or activates Parking Assist
PARKTRONIC If indicator lamp
0043is lit, Parking Assist
PARKTRONIC is deactivated.
i Parking Assist PARKTRONIC is automati-
cally activated when you turn the SmartKey to
position 2in the ignition lock.
Problems with Parking Assist PARKTRONIC Problem
Possible causes/consequences and
0050 0050Solutions Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. You also
hear a warning tone for
approximately two sec-
onds.
Parking Assist
PARKTRONIC is then
deactivated and the indi-
cator lamp on the
PARKTRONIC button
lights up. Parking Assist PARKTRONIC has malfunctioned and has been deacti-
vated.
X If problems persist, have Parking Assist PARKTRONIC checked at a
qualified specialist workshop. Only the red segments in
the Parking Assist
PARKTRONIC warning
displays are lit. Parking
Assist PARKTRONIC is
then deactivated. The Parking Assist PARKTRONIC sensors are dirty or there is inter-
ference.
X Clean the Parking Assist PARKTRONIC sensors (Y page 237).
X Switch the ignition back on. The problem may be caused by an external source of radio or ultra-
sound waves.
X Check to see if Parking Assist PARKTRONIC works at a different
location. Driving systems
141Driving and parking Z

X
If necessary, take a break.
X Confirm the message by pressing the 0076
button on the steering wheel.
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 increasing lapses in concentration, you will be warned again after 15 minutes at the
earliest. This will only happen if ATTEN-
TION ASSIST still detects typical indicators of
fatigue or increasing lapses in concentration.
Vehicles with the COMAND multimedia sys-
tem: if a warning is output in the multifunction
display, a service station search is performed in the multimedia system. You can select a servicestation and navigation to this service station will
then begin. This function can be activated or
deactivated in the multimedia system; see the
Digital Operator's Manual. Blind Spot Assist
General notes Blind Spot Assist monitors the areas on either
side of the vehicle that are not visible to the
driver with two lateral, rear-facing radar sen-
sors. A warning display in the exterior mirrors
draws your attention to vehicles detected in the
monitored area. If you then switch on the cor-
responding turn signal to change lane, you will
also receive an optical and audible warning.
Blind Spot Assist supports you from a speed of
approximately 20 mph (30 km/h).
Important safety notes G
WARNING
Blind Spot Assist does not react to:
R vehicles overtaken too closely on the side,
placing them in the blind spot area
R vehicles which approach with a large speed
differential and overtake your vehicle
As a result, Blind Spot Assist may not give
warnings in such situations. There is a risk of an accident.
Always observe the traffic conditions care-
fully, and maintain a safe lateral distance. Blind Spot Assist is only an aid. It may fail to
detect some vehicles and is no substitute for
attentive driving. Always ensure that there is
sufficient distance to the side for other road
users and obstacles.
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. Removing, tampering with, or
altering the device will void any warranties,
and is not permitted by the FCC. Do not tam-
per 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.
Radar sensors The radar sensors for Blind Spot Assist are inte-
grated into the rear bumper. Make sure that the
bumpers are free from dirt, ice or slush. The
sensors must not be covered, for example by
cycle racks or overhanging loads. 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 no longer work properly.
Monitoring range of the sensors In particular, the detection of obstacles can be
impaired if:
R there is dirt on the sensors or anything else
covering the sensors
R there is poor visibility, e.g. due to fog, heavy
rain or snow
R a narrow vehicle traveling in front, e.g. a
motorbike or bicycle
R the road has very wide lanes
R the road has narrow lanes
R you are not driving in the middle of the lane
R there are barriers or other road boundaries
Vehicles in the monitoring range are then not
indicated.
Blind Spot Assist monitors the area up to 10 ft
(3 m) behind your vehicle and directly next to it.
If the lanes are narrow, vehicles driving in the
lane beyond the lane next to your vehicle may be
indicated, especially if the vehicles are not driv-
ing in the middle of their lane. This may be the 150
Driving systemsDriving and parking

Display messages
Possible causes/consequences and
0050
0050Solutions Active
Active
Brake
Brake Assist
Assist
Functions
Functions Currently
Currently
Limited See Opera‐
Limited See Opera‐
tor's Manual tor's Manual Active Brake Assist is temporarily inoperative.
Possible causes are:
R the radar sensor system is temporarily inoperative, e.g. due to elec-
tromagnetic radiation emitted by nearby TV or radio stations or
other sources of electromagnetic radiation
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 message
disappears.
Active 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 128).
X Start the drive system again. Active Brake Active Brake
Assist: Assist:
System
SystemInop‐
Inop‐
erative
erative Active Brake Assist is unavailable due to a malfunction. Situation-
dependent parking assistance may also have failed.
X Visit a qualified specialist workshop immediately. Radar
Radar
Sensors
Sensors Dirty
Dirty
See Operator's Man‐
See Operator's Man‐
ual ual The radar sensor system is malfunctioning.
Possible causes are:
R Dirt on sensors
R Heavy rain or snow
R When driving on inter-urban roads without traffic or infrastructure,
e.g. in desert-like areas
Active Brake Assist is malfunctioning or is temporarily unavailable.
A warning tone also sounds.
Active Brake Assist is available again once the cause of the problem is
no longer present. The display message disappears.
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 128).
X Switch off the drive system.
X Clean all sensors (Y page 237).
X Start the drive system again.
The display message disappears. ã
Acoustic Vehicle Acoustic Vehicle
Indication Inopera‐ Indication Inopera‐
tive tive The sound generator is not working. The vehicle can still be driven;
however, no vehicle sounds can be generated. As a result, your vehicle
may not be heard by other road users until it is very close to them, or
it may not be heard at all.
X Drive with particular care, allowing for the possibility that other road
users may behave unpredictably.
X Visit a qualified specialist workshop. 174
Display
messagesOn-board computer and displays