2015 MERCEDES-BENZ B-CLASS HATCHBACK check engine light

Pre-entry climate control via key
(on-board computer) ......................1
85
Problem with the rear window
heating .......................................... 120
Problems with cooling with air
dehumidification ............................ 117
Setting the air distribution ............. 117
Setting the air vents ..................... .123
Setting the airflow ......................... 118
Setting the temperature ................ 117
Switching air-recirculation mode
on/off ............................................ 120
Switching on/off ........................... 116
Switching residual heat on/off ...... 122
Switching the rear window heat-
ing on/off ...................................... 119
Switching the ZONE function on/
off ................................................. .118
THERMOTRONIC (2-zone) auto-
matic climate control ..................... 115
Cockpit
Overview .......................................... 25
COLLISION PREVENTION ASSIST
PLUS
Activating/deactivating ................. 183
Display message ............................ 196
Operation/notes .............................. 62
COMAND
Generated electricity ..................... 137
COMAND display
Cleaning ......................................... 246
Combination switch ............................ 99
Consumption statistics (on-board
computer) .......................................... 176
Convenience closing feature .............. 83
Convenience opening feature ............ 83
Convenience opening/closing (air-
recirculation mode) ........................... 120
Coolant (engine)
Checking the level ......................... 240
Important safety notes .................. 283
Cooling
see Climate control
Copyright ............................................. 24
Cornering lamps
Changing bulbs .............................. 106 Cornering light function
Display message ............................ 201
Function/notes ............................ .100
Crash-responsive emergency light-
ing ....................................................... 103
Cruise control
Activation conditions ..................... 151
Cruise control lever ....................... 151
Deactivating ................................... 152
Display message ............................ 207
Driving system ............................... 150
Important safety notes .................. 151
LIM indicator lamp ......................... 151
Selecting ........................................ 151
Setting a speed .............................. 152
Storing and maintaining current
speed ............................................. 151
Cup holder
Centre console .............................. 233
Important safety notes .................. 233
Rear compartment ......................... 234 D
Data see Technical data
Daytime driving lights
Display message ............................ 202
Function/notes ................................ 98
Switching on/off (on-board com-
puter) ............................................. 186
Dealership
see Qualified specialist workshop
Declarations of conformity ................. 22
Departure time
Setting (on-board computer) .......... 184
Diagnostics connection ......................22
Digital speedometer .........................178
Dipped-beam headlamps
Changing bulbs .............................. 105
Display message ............................ 201
Setting for driving abroad (sym-
metrical) .......................................... 97
Setting for driving on the right/
left ................................................. 187
Switching on/off .............................. 98
DIRECT SELECT lever
Transmission ................................. 129 6
Index

allows you to continue steering the vehicle when
braking.
The ! ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
ABS works from a speed of about 8 km/h,
regardless of road-surface conditions. ABS
works on slippery surfaces, even when you only
brake gently.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately at a qualified specialist workshop.
If ABS is malfunctioning, other systems, includ-
ing driving safety systems, will also become
inoperative. Observe the information on the ABS warning lamp (Y page 216) and display mes-
sages which may be shown in the instrument
cluster (Y page 190).
Brakes X
If ABS intervenes: continue to depress the
brake pedal with force until the braking sit-
uation is over.
X To make a full brake application: depress
the brake pedal with full force.
If ABS intervenes when braking, you will feel a
pulsing in the brake pedal.
The pulsating brake pedal can be an indication
of hazardous road conditions; this serves as a
reminder to take extra care while driving. BAS (Brake Assist)
General notes BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking X
Keep the brake pedal depressed firmly until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. COLLISION PREVENTION ASSIST
PLUS
General notes i
Observe the "Important safety notes" sec-
tion (Y page 61).
COLLISION PREVENTION ASSIST PLUS consists of a distance warning function with an autono-
mous braking function and Adaptive Brake
Assist.
COLLISION PREVENTION ASSIST PLUS can help you to minimise the risk of a collision with the
vehicle in front or reduce the effects of such a
collision.
If COLLISION PREVENTION ASSIST PLUS
detects that there is a risk of a 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 62
Driving safety systemsSafety

G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering
As a result, the Adaptive Brake Assist may not intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic sit- uation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause Brake Assist to intervene.
If Adaptive Brake Assist is not available due to a malfunction in the radar sensor system, the
brake system remains available with full brake
boosting effect and BAS. Adaptive brake lights
The adaptive brake lights warn following traffic
in an emergency braking situation:
R by flashing brake lamps
R the hazard warning lamps are activated
If you brake sharply from a speed of more than
50 km/h or if braking is assisted by BAS or BAS
PLUS, the brake lamps flash rapidly. In this way,
traffic travelling behind you is warned in an even more noticeable manner.
If you brake sharply from a speed of more than
70 km/h to a standstill, the hazard warning
lamps are activated automatically. If the brakes
are applied again, the brake lamps light up con- tinuously. The hazard warning lamps switch off
automatically if you travel faster than 10 km/h. You can also switch off the hazard warning
lamps using the hazard warning button
(Y page 100). ESP
®
(Electronic Stability Program)
General notes i
Observe the "Important safety notes" sec-
tion (Y page 61). ESP
®
monitors driving stability and traction, i.e.
power transmission between the tyres and the
road surface.
If ESP ®
detects that the vehicle is deviating from
the direction desired by the driver, one or more
wheels are braked to stabilise the vehicle. The
engine output is also modified to keep the vehi- cle on the desired course within physical limits.
ESP ®
assists the driver when pulling away on
wet or slippery roads. ESP ®
can also stabilise
the vehicle during braking.
ETS (Electronic Traction System) i
Observe the "Important safety notes" sec-
tion (Y page 61).
ETS traction control is part of ESP ®
.
Traction control brakes the drive wheels indi-
vidually if they spin. This enables you to pull
away and accelerate on slippery surfaces, for
example if the road surface is slippery on one
side. In addition, more drive torque is transfer-
red to the wheel or wheels with traction.
Traction control remains active if you deactivate
ESP ®
.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 61). G
WARNING
If ESP ®
is malfunctioning, ESP ®
is unable to
stabilise the vehicle. In addition, other driving
safety systems are switched off. This increa-
ses the risk of skidding and an accident.
Drive on carefully. Have ESP ®
checked at a
qualified specialist workshop.
When towing your vehicle with the front axle
raised, observe the notes on ESP ®
(Y page 262).
When towing your vehicle away with the rear
axle raised, observe the notes on ESP ®
(Y page 262).
If the å ESP®
OFF warning lamp lights up
continuously, ESP ®
is deactivated.
If the ÷ ESP®
warning lamp and the å
warning lamp are lit continuously, ESP ®
is not
available due to a malfunction. Driving safety systems
65Safety Z

or traffic conditions. SPEEDTRONIC 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 there is a change of drivers, advise the new
driver of the speed stored.
Variable SPEEDTRONIC General notes
:
To activate or increase speed
; LIM indicator lamp
= To activate at the current speed/last stored
speed
? To activate or reduce speed
A To switch between cruise control and varia-
ble SPEEDTRONIC
B To deactivate cruise control
You can operate cruise control and variable
SPEEDTRONIC with the cruise control lever.
The LIM indicator lamp on the cruise control
lever indicates which system you have selected:
R LIM indicator lamp off: cruise control is
selected
R LIM indicator lamp on: variable SPEED-
TRONIC is selected
When the engine is running, you can use the
cruise control lever to limit the speed to any
speed between 30 km/h and the technically
permitted maximum speed of the vehicle.
Selecting variable SPEEDTRONICX Check whether LIM indicator lamp ;is on.
If it is on, variable SPEEDTRONIC is already
selected. If it is not, press the cruise control lever in the
direction of arrow A.
LIM indicator lamp ;in the cruise control
lever lights up. Variable SPEEDTRONIC is
selected.
Storing the current speed You can use the cruise control lever to limit the
speed to any speed above 30 km/h while the
engine is running.
X Briefly press the cruise control lever up :or
down ?.
The current speed is stored and shown in the multifunction display.
Storing or calling up the speed G
WARNING
If you call up the stored speed and it is lower
than the current speed, the vehicle deceler-
ates. If you do not know the stored speed, the vehicle could decelerate unexpectedly. There
is a risk of an accident.
Pay attention to the road and traffic condi-
tions before calling up the stored speed. If you do not know the stored speed, store the
desired speed again.
X Briefly pull the cruise control lever towards
you =.
Setting a speed
X To adjust the set speed in 10 km/h incre-
ments: briefly press the cruise control lever
up : beyond the pressure point for a higher
speed, or down ?for a lower speed.
or X Keep the cruise control lever pressed beyond
the pressure point until the desired speed is
set. Press the cruise control lever up :for a
higher speed or down ?for a lower speed.
X To adjust the set speed in 1 km/h incre-
ments:
briefly press the cruise control lever
up : to the pressure point for a higher speed
or down ?for a lower speed.
or X Keep the cruise control lever pressed to the
pressure point until the desired speed is set.
Press the cruise control lever up :for a
higher speed or down ?for a lower speed. Driving systems
153Driving and parking Z

X
Make sure that the windscreen wipers are
switched off.
X Pull release lever :on the bonnet.
The bonnet is released. X
Reach into the gap between the bonnet and
the radiator trim and press bonnet catch
lever ;to the left.
X Raise the bonnet. X
Pull support strut ?out of bracket A.
X Lift up support strut ?and insert it into yel-
low retaining clip =.
Closing the bonnet X
Raise the bonnet slightly and, at the same
time, remove support strut ?from yellow
retaining clip =.
X Swing support strut ?down and press it into
bracket Auntil it engages.
X Lower the bonnet and let it fall from a height
of approximately 20 cm.
X Check that the bonnet has engaged properly.
If the bonnet can be raised slightly, it is not
properly engaged. Do not press the bonnet
closed. Open the bonnet again and close it
with a little more force. Checking and adding other service
products
Checking the coolant level G
WARNING
The cooling system is pressurised, particu-
larly when the engine is warm. If you open the cap, you could be scalded if hot coolant
sprays out. There is a risk of injury.
Let the engine cool down before you open the
cap. Wear gloves and eye protection. Open
the cap slowly to release the pressure.
! The coolant level must only be checked and
corrected when the engine has cooled down
(coolant temperature under 40 †). Checking
the coolant level when the coolant tempera-
ture is over 40 † can lead to damage to the
engine or engine cooling system. X
Park the vehicle on a level surface.
Only check the coolant level when the vehicle
is on a level surface and the drive system has
cooled down.
X Turn the key to position 2in the ignition lock
(Y page 126).
X Check the coolant temperature display in the
instrument cluster.
The coolant temperature must be below
40 †.
X Turn the key to position 0in the ignition lock
(Y page 126).
X Slowly turn cap :anti-clockwise to allow
excess pressure to escape.
X Turn cap :further anti-clockwise and
remove it.
If the coolant is at the level of marker bar =
in the filler neck when cold, there is enough
coolant in coolant expansion tank ;.240
Engine compartmentMaintenance and care

Charging the 12‑
volt batteryG
WARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery. G
WARNING
Battery acid is caustic. There is a risk of injury. Avoid contact with the skin, eyes or clothing.
Do not breathe in any battery gases. Do not
lean over the battery. Keep the batteries out
of the reach of children. Immediately rinse off
battery acid thoroughly with plenty of clean
water and seek medical attention at once. G
WARNING
A discharged battery can freeze at tempera-
tures below freezing point. When jump-start-
ing the vehicle or charging the battery, gases can escape from the battery. There is a risk of
an explosion.
Allow the frozen battery to thaw out before
charging it or jump-starting.
! Only use battery chargers with a maximum
charging voltage of 14.8 V.
! Only charge the battery using the jump-start
connection point.
The jump-starting connection point is in the
engine compartment (Y page 258).
X Open the bonnet.
X Connect the battery charger to the positive
terminal and earth point in the same order as
when connecting the donor battery in the
jump-starting procedure (Y page 258).
If the indicator/warning lamps do not light up at
low temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may neither jump-start the vehicle nor charge the
battery. The service life of a battery that has
been thawed may be reduced. The starting char-
acteristics may be impaired, especially at low temperatures. Have the thawed battery
checked at a qualified specialist workshop.
Only charge the installed battery with a battery
charger which has been tested and approved by
Mercedes-Benz. A battery charger unit specially
adapted for Mercedes-Benz vehicles and tested
and approved by Mercedes-Benz is available as an accessory. This device permits charging of
the battery in position. Contact a Mercedes-
Benz Service Centre for information and availa-
bility. Read the battery charger's operating
instructions before charging the battery. 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.
Do not touch any high-voltage components
after an accident and never modify the vehi-
cle'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 could exceeda critical value. In this case, flammable gas
escapes through a vent valve in the vehicle's
underbody. The gas can ignite. There is a risk
of injury.
Leave the danger area immediately. Secure
the danger area at a suitable distance, whilst
observing legal requirements. 256
BatteriesBreakdown assistance

Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a pos- itive terminal and an earth point, in the engine compartment. G
WARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with the skin, eyes or clothing. Do not breathe in any battery gases. Do not lean over the battery. Keep the batteries out of the reach of children. Immediately rinse off battery acid
thoroughly with plenty of clean water and seek medical attention at once. G
WARNING
During charging and jump-starting, explosive gases can escape from the battery. There is a risk of an explosion.
Particularly avoid fire, naked flames, creating sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting. Do not lean over a battery. G
WARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosion.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described order when connecting and disconnecting
the jump leads.
R Never connect or disconnect the battery terminals while the engine is running. G
WARNING
A discharged battery can freeze at temperatures below freezing point. When jump-starting the
vehicle or charging the battery, gases can escape from the battery. There is a risk of an explosion.
Allow the frozen battery to thaw out before charging it or jump-starting.
! Avoid repeated and lengthy starting attempts.
Do not use a rapid-charging device to start the engine.
If the indicator/warning lamps do not light up at low temperatures, it is very likely that the dis-
charged battery has frozen. In this case you may neither jump-start the vehicle nor charge the
battery. The service life of a battery that has been thawed may be reduced. Have the thawed battery checked at a qualified specialist workshop.
If the 12 V battery is discharged, or after the vehicle has been jump-started, the Without chang‐ Without chang‐
ing
ing gear,
gear, consult
consult workshop
workshop message appears. There is a malfunction in the on-board voltage.
Visit a qualified specialist workshop immediately.
The drive system cannot be started if the 12 V battery is discharged. This is not dependant on
whether the high-voltage battery is charged or not. The vehicle cannot be jump-started if the high-
voltage battery is discharged. The high-voltage battery must first be charged. 258
Jump-startingBreakdown assistance