key MERCEDES-BENZ B-CLASS HATCHBACK 2008 Workshop Manual

Trailer towing*
186 Trailer towing*
Fitting the ball coupling
X Make a note of the ball coupling key num-
ber.
i You can use this number to obtain a
replacement key from a Mercedes-Benz
Service Centre. G
Risk of injury
If the ball coupling does not engage cor-
rectly when it is mounted, the vehicle/
trailer combination is not secured and the
trailer could come loose. This could cause
an accident. Fit the ball coupling carefully
and make sure that it engages in position
correctly.
Vehicles without ECO start/stop func-
tion: the attachable ball coupling is on the
right of the stowage compartment in the lug-
gage compartment (Y page 160).
X Open the stowage compartment on the
right-hand side of the luggage compart-
ment.
X Fold the trim downwards. Vehicles without ECO start/stop function
1
Ball coupling
2 Retainer strap
X Undo retainer strap 2.
X Remove ball coupling 1from the ball cou-
pling recess.
Vehicles with ECO start/stop function*:
the attachable ball coupling is in the ball cou-
pling recess in the stowage well underneath
the luggage compartment floor
(Y page 202).
X Open the luggage compartment floor. Vehicles with ECO start/stop function
1
Ball coupling
2 Ball coupling recess
X Remove ball coupling 1from the ball cou-
pling recess.2 1
Protective cap Operation
* optional
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Trailer towing*
187
X
Pull protective cap 1down in the direction
of the arrow out of the ball coupling recess.
X Place protective cap 1into the ball cou-
pling recess. 1
Key
2 Protective cap
X Pull protective cap 2off the lock in the
handwheel.
X Insert key 1into the ignition lock.
The red mark on the handwheel must be
aligned with the green area on the ball cou-
pling (fitting position). If this is not the case:
X Turn key 1in the direction of the arrow.
The key is released. 3
Ball coupling recess
4 Handwheel
X Pull handwheel 4away from the ball cou-
pling and turn it clockwise until it engages.
The green area on the ball coupling is
aligned with the red mark on the hand-
wheel.
X Insert the ball coupling in the direction of
the arrow into ball coupling recess 3until
it engages.
Handwheel 4turns so that green mark
5 on the handwheel is aligned with green
area 6on the ball coupling. 1
Key
2 Protective cap
5 Green mark on the handwheel
6 Green area on the ball coupling
X Turn key 1to the stop in the direction of
the arrow to lock.
X Remove key 1.
X Press protective cap 2onto the lock.
i You can store the key in the ball coupling
stowage compartment in the luggage com-
partment. Operation
* optional
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Trailer towing*
1881
Trailer power socket
X Fold trailer power socket 1down. G
Risk of accident
The ball coupling is only securely mounted
when the green mark on the handwheel is
aligned with the green area on the ball cou-
pling and the key can be removed. If the ball
coupling is not securely mounted, it may
come loose.
The ball coupling must be locked and the
key must be removed when towing a trailer.
This is the only way to guarantee that the
ball coupling is secured and cannot come
loose while the vehicle is in motion. If the
ball coupling cannot be locked and the key
cannot be removed, remove the ball cou-
pling and clean it. If the ball coupling can still not be fitted
(locked) after it has been cleaned, remove
the ball coupling. The trailer coupling must
then not be used to tow a trailer, as safe
operation is not guaranteed.
Have the entire trailer coupling checked at
a qualified specialist workshop. Mercedes-
Benz recommends that you use a
Mercedes-Benz Service Centre for this pur-
pose. In particular, work relevant to safety
or on safety-related systems must be car-
ried out at a qualified specialist workshop. Notes on towing a trailer
G
Risk of accident
When reversing the vehicle towards the
trailer, make sure there is nobody between
the trailer and the vehicle.
Couple and uncouple the trailer carefully. If
you do not couple the trailer to the towing
vehicle correctly, the trailer could become
detached.
Make sure that the following values are not
exceeded: R
the permissible trailer drawbar nose-
weight
R the permissible trailer load
R the permissible rear axle load of the tow-
ing vehicle
R the maximum permissible gross vehicle
weight of both the towing vehicle and the
trailer
You will find the applicable permissible val-
ues, which must not be exceeded, in the
vehicle documents.
You will find the values approved by the
manufacturer on the vehicle identification
plates and those for the towing vehicle in
the "Technical data" section.
You will find installation dimensions and loads
in the "Technical data" section
(Y page 289).
The maximum permissible trailer drawbar
noseweight on the ball coupling is 75 kg.
However, the actual drawbar load must not
exceed the value given on the trailer coupling
and trailer identification plates. The lowest
weight applies.
! Use a noseweight as close as possible to
the maximum permissible noseweight. Do Operation
* optional
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Trailer towing*
190note that the power output of the engine,
and consequently the vehicle's gradient-
climbing capability, decrease with increas-
ing altitude.
If the trailer swings from side to side:
X Do not accelerate.
X Do not counter-steer.
X Brake if necessary. G
Risk of accident
On no account should you attempt to draw
the vehicle/trailer combination out by
increasing speed. Removing the ball coupling
X Pull the protective cap off the lock in the
handwheel.
X Insert the key into the lock in the hand-
wheel.
X Turn the key clockwise.
The lock is unlocked.
X Hold the ball coupling. Pull the handwheel
away from the ball coupling and turn it
clockwise until it engages.
The green area on the ball coupling is
aligned with the red mark on the hand-
wheel. X
Pull out the ball coupling downwards.
X Clean the ball coupling if it is dirty.
X Vehicles without ECO start/stop func-
tion*: open the stowage compartment on
the right of the luggage compartment.
X Fold the trim downwards.
X Vehicles with start/stop function*:
open the luggage compartment floor.
X Remove the protective cap from the ball
coupling recess.
X Press the protective cap into the ball cou-
pling recess until it engages.
Storing the ball coupling X
Store the ball coupling with the key inser-
ted in the ball coupling recess.
X Vehicle without ECO start/stop func-
tion: Secure the ball coupling in place using
the retainer strap. G
Risk of accident
Do not carry the ball coupling in the vehicle
interior if it is not secured.
Otherwise, you and others could be injured
by the ball coupling being thrown around if
you: R
brake sharply
R change direction suddenly
R are involved in an accident Trailer power supply
When it leaves the factory, your vehicle's
trailer socket outlet is equipped with a per-
manent power supply and a power supply that
is switched on via the ignition lock.
The permanent power supply is supplied via
trailer socket pin 9.
The power supply that is switched on via the
ignition lock is supplied via trailer socket pin
10.
! You can connect consumers with a power
rating of up to 240 W to the permanent
power supply and up to 180 W to the power
supply that is switched on via the ignition
lock.
You must not charge a trailer battery using
the power supply.
The trailer's turn signal lamps are only guar-
anteed to function when bulbs are used.
You can obtain further information about
installing the trailer electrics from a qualified Operation
* optional
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Service
191
specialist workshop, e.g. a Mercedes-Benz
Service Centre.
X To switch the switched power supply on
or off: turn the key in the ignition lock to
position 2or 0, respectively. Trailer with 7-pin connector
If your trailer has a 7-pin connector, you can
connect it to the 13-pin socket on the ball
coupling using an adapter or, if necessary, an
adapter cable. Both of these can be obtained
at a qualified specialist workshop, e.g. at a
Mercedes-Benz Service Centre.
Fitting the adapter 1
Connector with lug
2 Socket with groove X
Fold down socket .
X Open the socket cover.
X Insert the connector with lug 1into
groove 2on the socket and turn the con-
nector clockwise to the stop.
X Make the cover engage.
X If you are using an adapter cable, secure
the cable to the trailer with cable ties.
! Make sure that there is sufficient cable
play so that the cable cannot become
detached when cornering. Service
ASSYST PLUS service interval display
The ASSYST PLUS service indicator informs
you of the next service due date. The multi-
function display shows the service due date:
Service A due in ..days
Service A due in .. km
Service A due now Next service due (example)
The letter indicates how much time the work-
shop will require to carry out the service work.
The letters displayed range from
Afor a short
service duration to Hfor a long service dura-
tion.
The ASSYST PLUS service interval indicator
does not take into account any periods of Operation
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Care
194nozzle of the high-pressure cleaner and the
vehicle (at least 30 cm).
Move the high-pressure cleaner nozzle
around when cleaning your vehicle.
Do not aim directly at any of the following:
R tyres
R door joint
R electrical components
R battery
R connectors
R lights
R seals
R trim elements
Damaged seals or electrical components
can lead to failures or leaks.
Cleaning the wiper blades and the out-
side of the windscreen G
Risk of injury
Before cleaning the windscreen or wiper
blades, turn the key in the ignition to 0.
Otherwise, the windscreen wipers may
move and injure you. X
Turn the key to position 1(Y page 62) in
the ignition lock.
X Set the windscreen wipers to position
I(Y page 82) on the combination switch.
X Turn the key to position 0(Y page 62) or
remove it when the wiper arms are vertical.
! Only fold the windscreen wipers away
from the windscreen when vertical. Other-
wise, you will damage the bonnet.
X Fold the wiper arms away from the wind-
screen.
X Wipe the windscreen and wiper blades with
a damp, lint-free cloth (e.g. a microfibre
cloth) and cleaning agent.
X Fold the wiper arms back on to the wind-
screen before the ignition is switched on.
! Do not clean the wiper blades too often
as this will result in damage to the surface
coating, leading to wiper noise.
Cleaning the windows !
Do not use dry cloths, abrasive products,
solvents or cleaning agents containing sol-
vents to clean the inside of the windows.
Clean the insides of the windows with a
damp cloth or commercially-available glass cleaner. Avoid touching the inside of the
rear windscreen and the side windows with
hard objects, e.g. ice scrapers or rings. You
could otherwise cause damage to the win-
dows, rear window heating or aerial on the
rear window.
i Anti-glare film retrofitted to the insides of
the windows could interfere with radio or
mobile phone reception, especially if it is
conductive or metal-coated film. Informa-
tion about anti-glare film can be obtained
from any Mercedes-Benz Service Centre.
Cleaning the headlamps X
Clean the plastic lenses of the headlamps
with a damp sponge.
! Only use washer fluid which is suitable
for plastic lenses. Unsuitable washer fluid
could damage the plastic lenses of the
headlamps.
Do not use the following:
R dry cloths
R abrasive cleaning agents
R solvents
R cleaning agents containing solvent Operation
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Display
messages 209Display messages Possible cause/consequence Possible solution
ESP inoperative See
Owner's Manual G
Risk of accident
ESP ®
is unavailable due to a malfunction.
The following systems are also unavaila-
ble:
R BAS
R the steering assistant STEER CONTROL
R hill start assist
R the tyre pressure loss warning system
The brake system continues to function
normally, but without the functions listed
above. X
Drive on carefully.
X Visit a qualified specialist workshop immedi-
ately. Vehicle Consult workshop
Safe operation of AUTOTRONIC* can no
longer be fully guaranteed. X
Stop in accordance with traffic conditions.
X Move the selector lever to P.
X Turn the key to position 0in the ignition lock.
X Wait at least 10 seconds before restarting the
engine.
X Move the selector lever to position Dor R.
X Drive on carefully.
X Have the transmission checked immediately at
a qualified specialist workshop. Shift to N to start
Vehicles with AUTOTRONIC*: the selector
lever is not in position
Nor P. X
Move the selector lever to position Nor P. Practical advi
ce
* optional
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Display
messages 220 Display messages Possible cause/consequence Possible solution
N Eng. oil level
Check level Vehicles with a petrol engine: the oil level
is too low. X
Check the oil level (Y page 172).
X If necessary, top up the motor oil.
X Have the engine checked for leaks if the engine
oil needs topping up more often than usual. N Eng. oil level Stop
car, turn eng. off Vehicles with a diesel engine: the oil level
is too low. There is a risk of engine dam-
age. X
Stop in accordance with traffic conditions.
X Switch off the engine.
X Top up the engine oil and check the level
(Y page 172). N Engine oil level
Reduce oil level Vehicles with a diesel engine: you have
added too much engine oil. There is a risk
of damage to the engine or to the catalytic
converter. X
Siphon off excess engine oil until it is at the
specified level. Observe the legal require-
ments. N Cannot measure oil
level Vehicles with a diesel engine: the meas-
uring system is faulty. X
Visit a qualified specialist workshop. I Key does not belong
to vehicle You have put the wrong key in the ignition
lock. X
Use the correct key. I Remove key The key is in the ignition lock. X
Remove the key. I Replace key The key needs to be replaced. X
Visit a qualified specialist workshop. Ñ SPEEDTRONIC inop-
erative
Speedtronic* and cruise control* are
faulty. X
Visit a qualified specialist workshop. Practical advi
ce
* optional
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Troubleshooting
223Problem Possible cause/consequence Suggested solutions
The indicator lamp in the
F/
1 rear-window heating button
is flashing. The rear-window heat-
ing has switched itself off prema-
turely or cannot be switched on. The on-board voltage is too low,
because too many consumers are
switched on. X
Switch off consumers that are not required, e. g. reading lamp or
interior lighting.
Once the battery is sufficiently charged, the rear window heating
will switch back on automatically. Vehicles with automatic child
seat recognition on the front-
passenger seat:
The
5 PASSENGER AIRBAG
OFF warning lamp on the centre
console is lit. A special Mercedes-Benz child
seat with automatic child seat
recognition has been fitted to the
front-passenger seat. The front-
passenger airbag has therefore
been disabled as desired.
G
Risk of injury
There is no child seat fitted to the
front-passenger seat. The auto-
matic child seat recognition is
malfunctioning. X
Remove electronic equipment from the front-passenger seat, for
example
R
notebook
R mobile phone
R cards with transponders, e.g. ski passes or access passes
If the 5 PASSENGER AIRBAG OFF warning lamp is still lit:
X Visit a qualified specialist workshop. You have started the engine with
the key. The indicator lamp in the
ECO start/stop function* button
does not light up or goes out
again after a short time. You have deactivated the ECO
start/stop function*. X
Activate the ECO start/stop function* again. The ECO start/stop function*is
not available due to a fault. X
Visit a qualified specialist workshop. Practical advice
* optional
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Troubleshooting
231Problem Possible cause/consequence Suggested solutions
You hear a warning tone.
Vehicles with AUTOTRONIC*:
You have:
R
switched off the engine
R opened the driver's door
R not moved the selector lever to
position P X
Move the selector lever to P.Accident
Problem Possible cause/consequence Suggested solutions
Fuel is leaking from the vehicle.
G
Risk of fire
The fuel line or the fuel tank has
been damaged. The leaking fuel
creates a risk of fire or explosion. X
Switch off the ignition immediately.
X Remove the ignition key.
Do not restart the engine under any circumstances. The leaking fuel
creates a risk of fire or explosion.
X Consult a qualified specialist workshop. You are unable to determine the
extent of the damage. X
Consult a qualified specialist workshop. You cannot detect any damage. X
Start the engine as normal. Practical advice
* optional
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