2015 MERCEDES-BENZ B-CLASS HATCHBACK air condition

Display messages
Possible causes/consequences and
M
MSolutions Front-passenger
Front-passenger
airbag enabled See airbag enabled See
Owner's Manual Owner's Manual The front-passenger front airbag is enabled during the journey
although:
R a child, a small adult or an object weighing less than the system
weight threshold is located on the front-passenger seat
or
R the front-passenger seat is not occupied
The system may detect objects or forces that are adding to the weight
applied to the seat.
G WARNING
The airbag may deploy unintentionally.
This poses an increased risk of injury. X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Safeguard the vehicle against rolling away (Y page 145).
X Switch the ignition off.
X Open the front-passenger door.
X Remove the child and the child restraint system from the front-
passenger seat.
X Make sure there are no objects applying additional force to the seat.
The system may otherwise detect the additional force and interpret the seat occupant's weight as greater than it actually is.
X Make sure that the seat is unoccupied, close the front-passenger
door and switch on the ignition.
X Observe the PASSENGER AIR BAG indicator lamps in the centre
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R a self-diagnosis takes place. The PASSENGER AIR BAG OFF and
PASSENGER AIR BAG ON indicator lamps light up simultaneously
for approximately six seconds
R the PASSENGER AIR BAG OFF indicator lamp must light up and
remain on after the self-diagnosis. If the indicator lamp is on, the
automatic front-passenger front airbag deactivation system has
disabled the front-passenger front airbag (Y page 42)
R the Front-passenger
Front-passenger airbag airbagenabled
enabled See
SeeOwner's
Owner's Manual
Manual
or Front-passenger
Front-passenger airbag
airbagdisabled
disabled See
SeeOwner's
Owner's Manual
Manual
display messages must not be shown in the multifunction display
X Wait for a period of at least 60 seconds until the necessary system
checks have been completed.
X Make sure that the display messages do not appear in the multi-
function display.
If these conditions are met, the front-passenger seat can be occupied again. Whether the PASSENGER AIR BAG OFF or ON indicator lamp
remains lit or goes out depends on how the automatic front-passenger front airbag deactivation system classifies the occupant.
If the conditions are not met, the system is not operating correctly.
X Consult a qualified specialist workshop immediately. 200
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Lane
Lane
Keeping
Keeping Assist
Assist
currently unavaila‐
currently unavaila‐
ble ble See
SeeOwner's
Owner's Man‐
Man‐
ual
ual Lane Keeping Assist is deactivated and 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
R there have been no lane markings for an extended period
R the lane markings are worn, dark or covered, e.g. by dirt or snow
Once the causes listed above no longer apply, the display message
goes out.
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 Safeguard the vehicle against rolling away (Y page 145).
X Clean the windscreen. Lane Lane
Keeping
Keeping Assist
Assist
inoperative
inoperative Lane Keeping Assist is faulty.
X Consult a qualified specialist workshop. Blind Spot Assist
Blind Spot Assist
currently unavaila‐ currently unavaila‐
ble ble
See
SeeOwner's
Owner's Man‐
Man‐
ual
ual Blind Spot Assist is temporarily inoperative.
Possible causes:
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 radar sensor system is outside the operating temperature range
The yellow 9indicator lamps also light up in the exterior mirrors.
Once the causes listed above no longer apply, the display message
goes out.
Blind Spot 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 Safeguard the vehicle against rolling away (Y page 145).
X Start the drive system again. Blind Spot Assist Blind Spot Assist
inoperative inoperative Blind Spot Assist is faulty.
The yellow
9indicator lamps also light up in the exterior mirrors.
X Consult a qualified specialist workshop. Park Assist cancel‐ Park Assist cancel‐
led led The driver's door is open and the driver's seat belt has not been fas-
tened.
X Repeat the parking process with the seat belt fastened and the
driver's door closed. 206
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions You inadvertently touched the multifunction steering wheel while
steering intervention was active.
X While steering intervention is active, make sure not to touch the
multifunction steering wheel. The vehicle has started to skid and ESP
®
has intervened.
X Use Active Parking Assist again later (Y page 158).Park Assist inoper‐ Park Assist inoper‐
ative ative You have just carried out a large number of turning or parking manoeu-
vres.
Active Parking Assist will become available again after approximately ten minutes (Y page 158).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off the drive system and start it again.
If the multifunction display still shows the display message:
X Consult a qualified specialist workshop. PARKTRONIC is faulty.
X Consult a qualified specialist workshop. Park Assist Park Assist
switched off switched off The vehicle is parked. A warning tone also sounds.
The display message disappears automatically. Traffic
Traffic
Sign
SignAssist
Assist
currently unavaila‐
currently unavaila‐
ble ble See
SeeOwner's
Owner's Man‐
Man‐
ual
ual 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 display message disappears.
Traffic Sign Assist is operational again. Traffic Traffic
Sign
SignAssist
Assist
inoperative
inoperative Traffic Sign Assist is faulty.
X Consult a qualified specialist workshop. Cruise control and
Cruise control and
SPEEDTRONIC inoper‐ SPEEDTRONIC inoper‐
ative ative SPEEDTRONIC and cruise control are malfunctioning.
A warning tone also sounds.
X Consult a qualified specialist workshop. Display
messages
207On-board computer and displays Z

Tyres
Display messages
Possible causes/consequences and
M
MSolutions Rectify tyre pres‐
Rectify tyre pres‐
sure sure The tyre pressure is too low in at least one of the tyres, or the tyre
pressure difference between the wheels is too great.
X Check the tyre pressures at the next opportunity (Y page 270).
X If necessary, correct the tyre pressure.
X Restart the tyre pressure monitor (Y page 272).Check tyre(s)
Check tyre(s) The tyre pressure in one or more tyres has dropped significantly. The
wheel position appears in the multifunction display.
A warning tone also sounds.
G WARNING
Underinflated tyres pose the following risks:
R the tyres may burst, especially as the load and vehicle speed
increase
R the tyres may wear excessively and/or unevenly, which may greatly
impair tyre traction
R the driving characteristics, as well as steering and braking, may be
greatly impaired
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do so.
X Safeguard the vehicle against rolling away (Y page 145).
X Check the tyres and, if necessary, follow the instructions for a flat
tyre (Y page 249).
X Check the tyre pressure (Y page 270).
X If necessary, correct the tyre pressure. Warning tyre defect Warning tyre defect The tyre pressure in one or more tyres has dropped suddenly. The
wheel position appears in the multifunction display.
G WARNING
If you drive with a flat tyre, there is a risk of the following hazards: R a flat tyre affects the ability to steer or brake the vehicle
R you could lose control of the vehicle
R continued driving with a flat tyre 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
manoeuvres. Pay attention to the traffic conditions as you do so.
X Safeguard the vehicle against rolling away (Y page 145).
X Check the tyres and, if necessary, follow the instructions for a flat
tyre (Y page 249). Display
messages
209On-board computer and displays Z

Safety systems
Problem
Possible causes/consequences and
M
MSolutions J
The yellow brake system
warning lamp is lit while
the drive system is run-
ning. The brake system is malfunctioning.
G WARNING
The braking characteristics may be affected.
There is a risk of an accident.
X Drive on taking extra care.
X Consult a qualified specialist workshop immediately. J
The yellow brake system
warning lamp is lit while
the drive system is run-
ning. RBS (Recuperative Brake System) is unavailable due to a malfunction.
G WARNING
The braking performance of the electric motor using recuperative
braking may be either reduced or not effective. 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 brak-
ing effect by applying the brake yourself.
The brake system continues to function normally, but without the
function listed above.
Braking efficiency may be impaired.
X Drive on taking extra care.
X Consult a qualified specialist workshop immediately. J
The red brake system
warning lamp is lit while
the drive system is run-
ning. A warning tone also
sounds. G
WARNING
The brake boosting effect is malfunctioning and the braking charac-
teristics may be affected.
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 Safeguard the vehicle against rolling away (Y page 145).
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction dis-
play. Warning and indicator lamps in the instrument cluster
215On-board computer and displays Z

Problem
Possible causes/consequences and
M
MSolutions J
The red brake system
warning lamp is lit while
the drive system is run-
ning. A warning tone also
sounds. There is insufficient brake fluid in the brake fluid reservoir.
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 Safeguard the vehicle against rolling away (Y page 145).
X Do not top up the brake fluid. Topping up will not rectify the fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction dis-
play. !֌J
The yellow ABS, ESP
®
,
ESP ®
OFF and brakes
warning lamps are lit
while the drive system is running. ABS (Anti-lock Braking System) has been deactivated due to a fault.
Therefore, BAS (Brake Assist), COLLISION PREVENTION ASSIST
PLUS, ESP ®
(Electronic Stability Program), RBS, PRE ‑SAFE®
, the
HOLD function, hill start assist and the adaptive brake lights, for
example, are also deactivated.
ATTENTION ASSIST is deactivated.
G WARNING
The braking performance of the electric motor using recuperative
braking may be either reduced or not effective. 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 brak-
ing effect by applying the brake yourself.
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you brake
hard, for example.
The steerability and braking characteristics may be severely affected. The braking distance may increase in an emergency braking situation.
If ESP ®
is not operational, ESP ®
is unable to stabilise the vehicle.
There is an increased danger of skidding and risk of an accident.
X Observe the additional display messages in the multifunction dis-
play.
X Drive on carefully.
X Consult a qualified specialist workshop immediately.
If the ABS control unit is malfunctioning, other systems may also not
be available, e.g. the navigation system. 216
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Tyres
Problem
Possible causes/consequences and
M
MSolutions h
The yellow tyre pressure
monitor warning lamp
(pressure loss/malfunc-
tion) is lit.
The tyre pressure monitor has detected a loss of pressure in at least
one of the tyres.
G WARNING
Underinflated tyres pose the following risks:
R the tyres may burst, especially as the load and vehicle speed
increase
R the tyres may wear excessively and/or unevenly, which may greatly
impair tyre traction
R the driving characteristics, as well as steering and braking, may be
greatly impaired
There is a risk of an accident.
X Stop the vehicle without making any sudden steering or braking
manoeuvres. Pay attention to the traffic conditions as you do so.
X Secure the vehicle against rolling away (Y page 145).
X Observe the additional display messages in the multifunction dis-
play.
X Check the tyres and, if necessary, follow the instructions for a flat
tyre (Y page 249).
X Check the tyre pressure (Y page 270).
X If necessary, correct the tyre pressure. h
The yellow tyre pressure
monitor warning lamp
(pressure loss/malfunc-
tion) flashes for approx-
imately one minute and
then remains lit.
The tyre pressure monitor is faulty.
G WARNING
The system is possibly unable to detect or register low tyre pressure.
There is a risk of an accident.
X Observe the additional display messages in the multifunction dis-
play.
X Consult a qualified specialist workshop immediately. Warning and indicator lamps in the instrument cluster
223On-board computer and displays Z

Washing the vehicle and cleaning the
paintwork
Automatic car wash G
WARNING
Braking efficiency is reduced after the vehicle has been washed. There is a risk of an acci-
dent.
After washing the vehicle, brake carefully
while paying attention to the traffic conditions in order to restore full braking efficiency.
! When the HOLD function is activated, the
vehicle brakes automatically in certain situa-
tions.
To avoid damage to the vehicle, deactivate
the HOLD function in the following or similar
situations:
R when towing away
R in a car wash
! When washing your vehicle in a tow-through
car wash, make sure that the selector lever is in position N, otherwise the vehicle could be
damaged.
! Make sure:
R the side windows are closed completely.
R the blower for the ventilation/heating is
switched off (OFF button is depressed/
airflow control is turned to position 0).
R the windscreen wiper switch is at position
0.
The vehicle could otherwise be damaged.
You can wash the vehicle in an automatic car
wash from the very start.
Wash off excess dirt before cleaning the vehicle
in an automatic car wash.
After using an automatic car wash, wipe off wax
from the windscreen and the wiper blades. This
will prevent smears and reduce wiping noises
caused by residue on the windscreen.
Washing by hand In some countries, washing by hand is only
allowed at specially equipped washing bays.
Observe the legal requirements for each indi-
vidual country. X
Do not use hot water and do not wash the
vehicle in direct sunlight.
X Use a soft sponge to clean.
X Use a mild cleaning agent, such as a car
shampoo approved by Mercedes-Benz.
X Thoroughly hose down the vehicle with a gen-
tle jet of water.
X Do not point the water jet directly towards the
air inlet.
X Use plenty of water and rinse out the sponge
frequently.
X Rinse the vehicle with clean water and dry
thoroughly with a chamois.
X Do not let the cleaning agent dry on the paint-
work.
When using the vehicle in winter, remove all
traces of road salt deposits carefully and as
soon as possible.
High-pressure cleaning equipment G
WARNING
The water jet of circular-jet nozzles (dirt grind- ers) can cause damage not visible from the
outside to tyres or chassis components. Com-
ponents damaged in this way can unexpect-
edly fail. There is a risk of an accident.
Do not use high-pressure cleaners with circu-
lar-jet nozzles to clean the vehicle. Have dam- aged tyres or chassis components replaced
immediately.
! Always maintain a distance of at least 30 cm
between the vehicle and the high-pressure
cleaner nozzle. Information about the correct
distance is available from the equipment
manufacturer.
Move the high-pressure cleaner nozzle
around when cleaning your vehicle.
Do not aim directly at any of the following:
R tyres
R door gaps, roof gaps, joints etc.
R electrical components
R battery
R connectors
R lights
R seals
R trim elements
R ventilation slots Care
243Maintenance and care Z