2014 MERCEDES-BENZ B-CLASS HATCHBACK light

Display messages
Possible causes/consequences and
M
MSolutions passenger front airbag deactivation system classifies the occu-
pant.
If the conditions are not met, the system is not operating correctly.
X Visit a qualified specialist workshop immediately.
Further information on the automatic front-passenger front airbag deactivation feature (Y page 49).Front-passenger Front-passenger
airbag airbag
enabled
enabled See
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 Secure the vehicle against rolling away (Y page 181).
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 inter- pret 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 AIRBAG indicator lamps in the centre
console and the multifunction display and check the following:
Seat unoccupied and ignition switched on:
R the PASSENGER AIR BAG OFF and PASSENGER AIR BAG ON
indicator lamps must light up simultaneously for approx-
imately six seconds
R the PASSENGER AIRBAG OFF indicator lamp must then light
up and remain lit. If the indicator lamp is on, the automatic 264
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions front-passenger front airbag deactivation system has disa-
bled the front-passenger front airbag (Y
page 50)
R the Front-passenger airbag enabled See Owner's Front-passenger airbag enabled See Owner's
Manual
Manual orFront-passenger
Front-passenger airbag
airbagdisabled
disabled See
SeeOwn‐
Own‐
er's Manual
er's Manual display messages must not be shown in the
multifunction display.
X Wait for a period of at least 60 seconds until the necessary sys-
tem checks have been completed.
X Make sure that the display messages do not appear in the mul-
tifunction display.
If these conditions are met, the front-passenger seat can be occu-
pied again. Whether the PASSENGER AIRBAG OFF or ON indicator
lamp remains lit or goes out depends on how the automatic front-
passenger front airbag deactivation system classifies the occu-
pant.
If the conditions are not met, the system is not operating correctly.
X Visit a qualified specialist workshop immediately.
Further information on the automatic front-passenger front airbag deactivation feature (Y page 49).Lights
i Vehicles with LED light bulbs in the light clusters:
The display message for the corresponding light will only appear if all the LEDs have failed. Display messages
Possible causes/consequences and
M MSolutions b
Left dipped beam Left dipped beam
or
Right dipped Right dipped
beam
beam The left or right-hand dipped-beam headlamp is faulty.
X Halogen headlamp: replace the bulb (Ypage 128).
X LED headlamps: consult a qualified specialist workshop. b
Trailer left tail Trailer left tail
lamp lampor
Trailer
Trailer
right tail lamp
right tail lamp The left or right-hand trailer tail lamp is faulty.
X Observe the manufacturer's operating instructions. b
Trailer left turn Trailer left turn
signal signal
orTrailerTrailer
right turn signal
right turn signal The left or right-hand trailer turn signal lamp is faulty.
X Observe the manufacturer's operating instructions. Display
messages
265On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions b
Rear fog lamp
Rear fog lamp The rear foglamp is faulty.
X Tail lamps (vehicles with halogen headlamps): replace the
bulb (Y page 128).
X Tail lamps (vehicles with LED headlamps): visit a qualified
specialist workshop. b
Front Front
left
leftparking
parking
lamp
lamp orFront
Front
right parking lamp
right parking lamp The front left or front right parking lamp is faulty.
X Visit a qualified specialist workshop. b
Reversing light Reversing light The reversing lamp is faulty.
X Tail lamps (vehicles with halogen headlamps): replace the
bulb (Y page 128).
X Tail lamps (vehicles with LED headlamps): visit a qualified
specialist workshop. b
Left tail lamp Left tail lamp
or
Right tail lamp
Right tail lamp The left or right-hand tail lamp is faulty.
X Visit a qualified specialist workshop. b
Left daytime driv‐ Left daytime driv‐
ing lamp ing lamp
orRight
Right
daytime driving
daytime driving
lamp lamp The left or right-hand daytime driving lamp is faulty.
X Visit a qualified specialist workshop. b
Malfunction See Malfunction See
Owner's Manual Owner's Manual The exterior lighting is faulty.
X Visit a qualified specialist workshop. Vehicles with trailer tow hitch: a fuse may have blown.
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 Check the fuses (Y page 349).
X If necessary, replace the blown fuse. Observe the warning notes
as you do so.
If the display message continues to be displayed: X Visit a qualified specialist workshop. Display
messages
267On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions b
AUTO AUTO
lights
lights inoper‐
inoper‐
ative
ative The light sensor is faulty.
X Visit a qualified specialist workshop. b
Switch off lights Switch off lights The lights are still switched on when you leave the vehicle. A
warning tone also sounds.
X Turn the light switch to Ã.Adaptive Adaptive
Main-beam
Main-beam
Assist currently
Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual Adaptive Highbeam Assist is deactivated and temporarily inoper-
ative. 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 again, the
Adaptive Main-beam Assist available again
Adaptive Main-beam Assist available again message is
displayed.
Adaptive Highbeam Assist is operational again. Adaptive Adaptive
Main-beam
Main-beam
Assist inoperative
Assist inoperative Adaptive Highbeam Assist is faulty.
X
Visit a qualified specialist workshop. Engine
Display messages
Possible causes/consequences and
M MSolutions +
Top Top
up
upcoolant
coolant See
See
Owner's Manual
Owner's Manual The coolant level is too low.
! Avoid making long journeys with too little coolant in the engine
cooling system. The engine will otherwise be damaged.
X Top up the coolant, observing the warning notes before doing so
(Y page 322).
X If the coolant needs topping up more often than usual, have the
engine coolant system checked at a qualified specialist work-
shop. ? The fan motor is faulty.
X If the coolant temperature is below 120 †, you can continue
driving to the nearest qualified specialist workshop.
X Avoid putting the engine under heavy load as you do so, e.g.
driving in mountainous terrain and stop-start traffic. 268
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Lane Keeping
Lane Keeping
Assist currently Assist currently
unavailable See unavailable See
Owner's Manual Owner's Manual 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 Secure the vehicle to prevent it from rolling away (Y page 181).
X Clean the windscreen. Lane Keeping Lane Keeping
Assist inoperative Assist inoperative Lane Keeping Assist is faulty.
X Visit a qualified specialist workshop. Blind Spot Assist
Blind Spot Assist
currently unavail‐ currently unavail‐
able See Owner's able See Owner's
Manual Manual Blind Spot Assist 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 radar sensor system is outside the operating temperature
range
The yellow 9indicator lamps also light up in the exterior mir-
rors.
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 Secure the vehicle against rolling away (Y page 181).
X Restart the engine. 272
Display
messagesOn-board computer and displays

Display messages
Possible causes/consequences and
M
MSolutions Active Blind Spot
Active Blind Spot
Assist not availa‐ Assist not availa‐
ble when towing a ble when towing a
trailer See Own‐ trailer See Own‐
er's Manual er's Manual
. Blind Spot Assist is deactivated while towing a trailer.
You have established the electrical connection between the trailer
and your vehicle.
X Press aon the steering wheel to confirm the display mes-
sage. Blind Spot Assist Blind Spot Assist
inoperative inoperative Blind Spot Assist is faulty.
The yellow
9indicator lamps also light up in the exterior mir-
rors.
X Visit a qualified specialist workshop. Park Park
Assist
Assist cancel‐
cancel‐
led
led The driver's door is open and the driver's seat belt has not been
fastened.
X Repeat the parking process with the seat belt fastened and the
driver's door closed. 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 206).Park Park
Assist
Assist inoper‐
inoper‐
ative
ative You have just carried out a large number of turning or parking
manoeuvres.
Active Parking Assist will become available again after approx-
imately ten minutes (Y
page 206).
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions.
X Switch off and restart the engine.
If the display message continues to be displayed: X Visit a qualified specialist workshop. PARKTRONIC is faulty.
X Visit 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. Display
messages
273On-board computer and displays Z

Display messages
Possible causes/consequences and
M
MSolutions _
Before starting Before starting
the engine, turn the engine, turn
the the
steering
steering wheel.
wheel. The electric steering lock was unable to unlock the steering.
X Remove the key from the ignition lock.
X To unlock the steering, move the steering wheel slightly.
X Insert the key into the ignition lock again. Telephone No ser‐
Telephone No ser‐
vice vice Your vehicle is outside the network provider's transmitter/
receiver range.
X Wait until the mobile phone operational readiness symbol
appears in the multifunction display. ¥
Top Top
up
upwasher
washer fluid
fluid The washer fluid level in the washer fluid reservoir has dropped
below the minimum.
X Top up the washer fluid (Y page 322).Wiper malfunction‐ Wiper malfunction‐
ing ing The windscreen wipers are defective.
X Visit a qualified specialist workshop. Hazard warning
Hazard warning
lamps malfunction‐ lamps malfunction‐
ing ing The hazard warning lamps are faulty.
X Visit a qualified specialist workshop. Key
Display messages
Possible causes/consequences and
M
MSolutions Â
Key does not Key does not
belong to vehicle belong to vehicle You have put the wrong key in the ignition lock.
X Use the correct key. Â
Replace key Replace key The key needs to be replaced.
X Visit a qualified specialist workshop. Â
Change key batter‐ Change key batter‐
ies ies The key battery is discharged.
X Replace the battery (Y page 90). Display
messages
283On-board computer and displays Z

Safety
Seat belts Problem
Possible causes/consequences and
M
MSolutions ü
Only for certain coun-
tries: the red seat belt
warning lamp lights up
for 6 seconds after the
engine starts.
The seat belt warning lamp reminds the driver and front passenger
to fasten their seat belts.
X Fasten your seat belt (Y page 44).ü
Only for certain coun-
tries: the red seat belt
warning lamp lights up
after the engine starts.
In addition, a warning
tone sounds for up to
6 seconds.
The driver's seat belt is not fastened.
X Fasten your seat belt (Y page 44).
The warning tone ceases. ü
The red seat belt warn-
ing lamp lights up after
the engine starts, as
soon as the driver's or
the front-passenger
door is closed.
The driver or passenger has not fastened their seat belt.
X Fasten your seat belt (Y page 44).
The warning lamp goes out. There are objects on the front-passenger seat.
X Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out. ü
The red seat belt warn-
ing lamp flashes and an
intermittent audible
warning sounds. The driver or passenger has not fastened their seat belt. At the
same time, you are driving faster than 25 km/h or have briefly
driven faster than 25 km/h.
X Fasten your seat belt (Y page 44).
The warning lamp goes out and the intermittent warning tone
ceases. There are objects on the front-passenger seat. At the same time,
you are driving faster than 25 km/h or have briefly driven faster
than 25 km/h.
X Remove the objects from the front-passenger seat and stow
them in a secure place.
The warning lamp goes out and the intermittent warning tone
ceases. Wa
rning and indi cator lamps in the instrument cluster
285On-board computer and displays Z