trailer MERCEDES-BENZ B-CLASS HATCHBACK 2011 Service Manual

Safety systems
Problem Possible causes/consequences and
M Solutions
J
The red brake system
warning lamp comes on
while the engine is run-
ning. A warning tone
also sounds. There is insufficient brake fluid in the brake fluid reservoir.
G WARNING
The braking effect may be impaired.
There is a risk of 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 Engage the electric parking brake.
X Do not top up the brake fluid. Topping up will not remedy the
fault.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. !
The yellow ABS warning
lamp is lit while the
engine is running. ABS (Anti-lock Brake System) has been deactivated due to a fault.
For this reason, BAS (Brake Assist), BAS PLUS, ESP ®
(Electronic
Stability Program), PRE-SAFE ®
, the HOLD function, hill start assist,
the adaptive brake lights and ESP ®
trailer stabilisation are also
deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
This limits the steerability of the vehicle when braking and may
increase the braking distance.
If ESP ®
is deactivated or not operational, the vehicle's stability
during standard driving manoeuvres is reduced.
There is a risk of accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic trans-
mission, will not be available. Warning and indicator lamps in the instrument cluster
233On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
!
The yellow ABS warning
lamp is lit while the
engine is running. ABS is temporarily unavailable. Therefore, BAS, BAS PLUS, ESP
®
,
EBD (electronic brake force distribution), PRE-SAFE ®
, the HOLD
function, hill start assist, the adaptive brake lights and ESP ®
trailer
stabilisation, for example, are also deactivated.
Possible causes:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
This limits the steerability of the vehicle when braking and may
increase the braking distance.
If ESP ®
is deactivated or not operational, the vehicle's stability
during standard driving manoeuvres is reduced.
There is a risk of accident.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 234
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
!
The yellow ABS warning
lamp is lit while the
engine is running. A
warning tone also
sounds. EBD is faulty. Therefore, ABS,B
AS, BAS PLUS, ESP®
, PRE-SAFE ®
,
the HOLD function, hill start assist, the adaptive brake lights and
ESP ®
trailer stabilisation, for example, are not available either.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continue sto function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
This limits the steerability of the vehicle when braking and may
increase the braking distance.
If ESP ®
is deactivated or not operational, the vehicle's stability
during standard driving manoeuvres is reduced.
There is a risk of accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. J֌!
The red brake warning
lamp, the yellow ESP
®
and ESP ®
OFF warning
lamps and the yellow
ABS warning lamp are
lit while the engine is
running. ABS and ESP
®
are malfunctioning. Therefore, BAS, BAS PLUS,
EBD,P RE-SAFE ®
, the HOLD function ,hill start assist, the adaptive
brake lights and ESP ®
trailer stabilisation, for example, are not
available either.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
This limits the steerability of the vehicle when braking and may
increase the braking distance.
If ESP ®
is deactivated or not operational, the vehicle's stability
during standard driving manoeuvres is reduced.
There is a risk of accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
235On-board computer and displays Z

Problem Possible causes/consequences and
M Solutions
÷
The yellow ESP
®
warn-
ing lamp flashes while
the vehicle is in motion. ESP
®
or traction control has intervened because there is a risk of
skidding or at least one wheel has started to spin.
Cruise control or DISTRONIC PLUS is deactivated.
X Only depress the accelerator pedal as far as necessary when
pulling away.
X Accelerate more gently while the vehicle is in motion.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
.
For exceptions, see: (Y page 66).å
The yellow ESP
®
OFF
warning lamp is lit while
the engine is running. ESP
®
and ESP ®
trailer stabilisation are deactivated. ESP ®
will not
stabilise the vehicle if it starts to skid or if awheel starts to spin.
G WARNING
If ESP ®
is deactivated, the vehicle's stability during standard driv-
ing manoeuvres is reduced.
There is a risk of accident.
X Reactivate ESP ®
.
For exceptions, see: (Y page 66).
X Adapt your driving style to suit the road and weather conditions.
If ESP ®
cannot be activated:
X Have ESP ®
checked at a qualified specialist workshop. ֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, BAS PLUS, PRE-SAFE ®
, the HOLD function, hill start
assist, the adaptive brake lights and ESP ®
trailer stabilisation are
not available due to a malfunction.
ATTENTION ASSIST is deactivated.
G WARNING
ESP ®
will not stabilise the vehicle if it starts to skid or if a wheel
starts to spin.
The brake system continues to function normally, but without the
functions listed above.
If ESP ®
is deactivated or not operational, the vehicle's stability
during standard driving manoeuvres is reduced.
There is a risk of accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. 236
Warning and indicator lamps in the instrument clusterOn-board computer and displays

Problem Possible causes/consequences and
M Solutions
֌
The yellow ESP
®
and
ESP ®
OFF warning
lamps are lit while the
engine is running. ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilisation are temporarily not available.
The adaptive brake lights and BAS PLUS may also have failed.
ATTENTION ASSIST is deactivated.
G WARNING
ESP ®
will not stabilise the vehicle if it starts to skid or if a wheel
starts to spin.
Self-diagnosis is not yet complete.
The brake system continues to function normally, but without the
functions listed above.
If ESP ®
is deactivated or not operational, the vehicle's stability
during standard driving manoeuvres is reduced.
There is a risk of accident.
X Carefully drive on a suitable stretch of road, making slight steer-
ing movements, at a speed above 20 km/h.
The functions mentioned above are available again when the
warning lamp goes out.
If the warning lamp is still on:
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop. Warning and indicator lamps in the instrument cluster
237On-board computer and displays Z

Cleaning the exhaust pipe
!
Do no tclean the exhaust pipe with alka-
line-based cleaning agents, such as wheel
cleaner.
X Clean the exhaust pipe with a chrome care
produc ttested and approved by Mercedes-
Benz.
Impurities combined with the effects of road
grit and corrosive environmental factors may
cause flash rust to form on the surface. You
can restore the original shine of the exhaust
pipe by cleaning it regularly, especially in win-
ter and after washing.
Cleaning the trailer tow hitch H
Environmental note
Dispose of oily and greasy cloths in an envi-
ronmentally-responsible manner.
! Do not clean the ball coupling with a high-
pressure cleaner. Do not use solvents.
! Observe the note on care provided by the
trailer manufacturer. X
Remove rust, e.g. with a wire brush.
X Remove dirt with a clean, lint-free cloth or
a brush.
X After cleaning, lightly oil or grease ball cou-
pling :.
X Check that the vehicle's trailer tow hitch is
working properly.
i Maintenance of the ball coupling and
trailer tow hitch can also be performed at a qualified specialist workshop, e.g. a
Mercedes-Benz Service Centre. Interior care
Cleaning the display !
For cleaning, do not use any of the fol-
lowing:
R alcohol-based thinner or petrol
R abrasive cleaning agents
R commercially-available household clean-
ing agents
These may damage the display surface. Do
not put pressure on the display surface
when cleaning. This could lead to irrepara-
ble damage to the display.
X Before cleaning the display, make sure that
it is switched off and has cooled down.
X Clean the display surface using a commer-
cially available microfibre cloth and TFT/
LCD display cleaner.
X Dry the display surface using a dry micro-
fibre cloth.
Cleaning the plastic trim G
WARNING
When cleaning the steering wheel boss and
dashboard, do not use cockpit sprays or
cleaning agents containing solvents. Cleaning
agents containing solvents cause the surface
to become porous, and as aresult plastic
parts may break away and be thrown around
the interior when an airbag is deployed, which
may result in severe injuries.
! Do not affix the following to plastic surfa-
ces:
R stickers
R films
R scented oil bottles or similar items
You could otherwise damage the plastic. Care
271Maintenance and care Z

Vehicles with a trailer tow hitch: if you intend
to use the vehicle for towing, fold out the ball
coupling (Y
page 183) and connect the tow-
bar to it.
Removing the towing eye X
Loosen the towing eye and unscrew it.
X Attach cover :to the bumper and press
until it engages.
X Place the towing eye and the tyre inflation
compressor in the stowage space in the
luggage compartment under the luggage
compartment floor (Y page 274).Towing the vehicle with the front axle
raised
! The ignition must be switched off if you
are towing the vehicle with the front axle
raised. Intervention by ESP ®
could other-
wise damage the brake system.
X Turn the key to position 2in the ignition
lock.
X When the vehicle is stationary, depress the
brake pedal and keep it depressed.
X Vehicles with manual transmission:
shift to neutral.
or
X Vehicles with automatic transmission:
shift the automatic transmission to posi-
tion P.
X Release the brake pedal.
X Release the electric parking brake.
X Deactivate automatic locking
(Y page 203).
X Switch on the hazard warning lamps
(Y page 99).
X Turn the key in the ignition lock to position
0and leave the key in the ignition lock.
When towing yourv ehicle with the frontaxle
raised, it is important tha tyou observe the
safety instructions (Y page 284). Towing the vehicle with both axles on
the ground
G
WARNING
The power assistance for the steering and the
brake force booster do not work when the
engine is not running. You will then need
much more effort to brake and steer the vehi-
cle. Adapt your style of driving accordingly.
i In order to signal a change of direction
when towing with the hazard warning lamps
switched on, use the combination switch as
usual.Int his case, only the turn signals for
the desired direction flash. When the com-
bination switch is reset, the hazard warning
lamps start flashing again.
Vehicles with automatic transmission: the
automatic transmission automatically shifts
to position Pwhen you open the driver's or
front-passenger door or when you remove the
key from the ignition lock. In order to ensure
that the automatic transmission stays in posi-
tion Nwhen towing the vehicle, you must
observe the following points:
X Make sure that the vehicle is stationary.
X Turn the key to position 2in the ignition
lock.
X Depress and hold the brake pedal.
X Shift the automatic transmission to posi-
tion N.
Vehicles with manual transmission:
X Turn the key to position 2in the ignition
lock.
X Depress and hold the brake pedal.
X Engage neutral.
Vehicles with manualo r automatic trans-
mission:
X Leave the key in position 2in the ignition
lock.
X Release the brake pedal.
X Release the electric parking brake.
X Switch on the hazard warning lamps
(Y page 99). 286
Towing and tow-startingBreakdown assistance

It is important that you observe the safety
instructions when towing away yourv ehicle
(Y page 284). Transporting the vehicle
! Only lash the vehicle down by the wheels
or wheel rims, not by parts of the vehicle
such as axle or steering components. Oth-
erwise, the vehicle could be damaged.
X Vehicles with manual transmission:
shift to neutral.
X Vehicles with automatic transmission:
turn the key to position 2in the ignition
lock.
X Shift the transmission to position N.
As soon as the vehicle is loaded:
X Preven tthe vehicle from rolling away by
applying the electric parking brake.
X Vehicles with manual transmission:
shift to first gear or reverse gear.
X Vehicles with automatic transmission:
shift the transmission to position P.
X Turn the key to position 0in the ignition
lock and remove it.
X Secure the vehicle.
The towing eyes or trailer tow hitch can be
used to pull the vehicle onto a trailer or trans-
porter if you wish to transport it. Tow-starting (emergency engine
starting)
! Vehicles with automatic transmission
must not be tow-started. Otherwise, you
could damage the automatic transmission.
Before tow-starting the following conditions
must be fulfilled:
R the battery is connected.
R the engine has cooled down.
R the catalytic converters have cooled down. X
Switch on the hazard warning lamps
(Y page 99).
X Fit the towing eye (Y page 285).
X Secure the rigid towing bar or the towing
rope.
X Depress and hold the brake pedal.
X Turn the key to position 2in the ignition
lock.
X Depress the clutch pedal and keep it
depressed.
X Engage neutral.
X Release the brake pedal.
X Tow-start the vehicle.
X Engage second gear.
X Release the clutch pedal slowly without
depressing the accelerator pedal.
The engine is started.
X Depress the clutch pedal and shift to neu-
tral.
X Stop at a suitable place.
X Secure the vehicle by applying the electric
parking brake.
X Remove the rigid towing bar or towing rope.
X Remove the towing eye (Y page 286).
X Switch off the hazard warning lamps.
When tow-starting, it is important that you
observe the safety instructions (Y page 284)
and the legal requirements in each respective
country. Electrical fuses
Important safety notes
G
WARNING
Only use fuses that have been approved for
Mercedes-Ben zvehicles and which have the
correct fuse rating for the systems con-
cerned. Do not attempt to repair or bridge
faulty fuses. Using fuses which have not been
approved or attempting to repair or bridge
faulty fuses could cause the fuse to be over-
loaded and result in a fire. Have the cause Electrical fuses
287Breakdown assistance
Z

R
Check the tyre for foreign objects.
R Chec kwhether the wheel is losing air or the
valve is leaking.
If you are unable to rectify the damage, con-
tact a qualified specialist workshop. H
Environmental note
Check the tyre pressure regularly, at least
every 14 days.
You will find a table of tyre pressures for var-
ious operating conditions on the inside of
your vehicle's fuel filler flap.
Operation with a trailer: the applicable
value for the rear tyres is the maximum tyre
pressure value stated in the table inside the
fuel filler flap.
The table inside the fuel filler flap may state
tyre pressures for different load conditions.
These are defined in the table as different
numbers of passengers and amounts of lug-
gage. The actual number of seats may vary –
for more information, please refer to the vehi-
cle's registration documents.
If tyre sizes are not specified, the tyre pres-
sures stated on the tyre pressure information
label apply for all tyres approved for this vehi-
cle. If a tyre size precedes a tyre pressure, the tyre
pressure information following is only valid
for that tyre size.
Use a suitable pressure gauge to check the
tyre pressure. The outer appearance of a tyre
does not permit any reliable conclusion about
the tyre pressure. If possible, only correct tyre pressures when
the tyres are cold.
The tyres are cold:
R
if the vehicle has been parked with the tyres
out of direct sunlight for at least three
hours and
R if the vehicle has not been driven further
than 1.6 km
Depending on the ambient temperature, the
speed you are driving at and the load on the
tyres, the tyre temperature may change and
thereby the tyre pressure: 10 kPa (0.1 bar/
1.5 psi) per 10 †. Take this into account
when checking the pressure of warm tyres.
Only correct the tyre pressure if it is too low
for the current operating conditions.
Driving with tyre pressure that is too high or
too low can:
R shorten the service life of the tyres
R cause increased tyre damage
R have a negative effect on handling charac-
teristics and thus the driving safety (e.g.
aquaplaning)
i The tyre pressure values given for low
loads are minimum values which offer you
good ride comfort characteristics.
However, you can also use the values given
for higher loads. These are permissible and
will not adversely affect the running of the
vehicle. Tyre pressure loss warning system
Important safety notes While the vehicle is in motion, the tyre pres-
sure loss warning system monitors the set
tyre pressure using the rotational speed of
the wheels. This enables the system to detect
significant pressure loss in a tyre. If the speed
of rotation of a wheel changes as a result of
a loss of pressure, a corresponding warning
message will appearint he multifunction dis-
play. 296
Tyre pressureWheels and tyres

The tyre pressure warning system does not
warn you of an incorrectly set tyre pressure.
Observe the notes on the recommended tyre
pressure (Y page 295).
The tyre pressure loss warning system does
not replace the need to regularly check your
vehicle's tyre pressures, since an even loss of
pressure on several tyres at the same time
cannot be detected by the tyre pressure loss
warning system.
The tyre pressure monitor is not able to warn
you of a sudden loss of pressure, e.g. if the
tyre is penetrated by a foreign object. In the
event of a sudden loss of pressure, bring the
vehicle to a halt by braking carefully. Avoid
abrupt steering manoeuvres.
The function of the tyre pressure loss warning
system is limited or delaye dif:
R snow chains are fitted to you rvehicle's
tyres.
R road conditions are wintry.
R you are driving on sand or gravel.
R you adopt a very sporty driving style (cor-
nering at high speeds or driving with high
rates of acceleration).
R you are towing a very heavy or large trailer.
R you are driving with a heavy load (in the
vehicle or on the roof).
Restarting the tyre pressure loss warn-
ing system Restart the tyre pressure loss warning system
if you have:
R changed the tyre pressure
R changed the wheels or tyres
R fitted new wheels or tyres
X Before restarting, consult the table of tyre
pressures on the inside of the fuel filler flap
to ensure that the tyre pressure in all four
tyres is set correctly for the respective
operating conditions.
The tyre pressure loss warning system can
only give reliable warnings if you have set
the correct tyre pressure. If an incorrect tyre pressure is set, these incorrect values
will be monitored.
X Observe the notes in the section on tyre
pressures (Y page 295).
X Make sure that the key is in position 2in
the ignition lock.
X Press the =or; button to select the
Service menu.
X Press the 9or: button to select
Tyre pressure .
X Press the abutton.
The Run Flat Indicator active Restart with OK message appears in the
multifunction display.
If you wish to confirm the restart:
X Press the abutton.
The Tyre press. now OK? message
appears in the multifunction display.
X Press the 9or: button to select
Yes .
X Press the abutton.
The Run Flat Indicator restarted message appears in the multifunction dis-
play.
After a teach-in period, the tyre pressure
loss warning system will monitor the set
tyre pressures of all four tyres.
or
If you wish to cancel the restart:
X Press the %button.
or
X If the Tyre press. now OK? message
appears, use the 9or: button to
select Cancel .
X Press the abutton.
The tyre pressure values stored at the last
restart will continue to be monitored. Tyre pressure
297Wheels and tyres Z