2008 MERCEDES-BENZ B-CLASS HATCHBACK trailer

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*
189
not use a noseweight of less than 50 kg,
otherwise the trailer may come loose.
Bear in mind that the payload and the rear
axle load are reduced by the actual nose-
weight.
i The height of the ball coupling changes
with the load of the vehicle. If necessary,
use a trailer with a height-adjustable draw-
bar.
Coupling up a trailer G
Risk of injury
Do not disconnect a trailer with an engaged
overrun brake. Otherwise, your hand could
become trapped between the bumper and
drawbar.
! Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the rebound-
ing of the overrun brake.
X Position the trailer level behind the vehicle.
X Couple up the trailer.
X Establish the electrical connection
between the vehicle and the trailer. Driving tips In Germany, the maximum permitted speed
for vehicle/trailer combinations is 80 km/h.
G
Risk of accident
A maximum speed of 80 km/h should not
be exceeded, even in countries where
higher speeds are permitted for vehicle/
trailer combinations. This lowers the risk of
an accident.
When towing a trailer, your vehicle's handling
characteristics will be different in comparison
to when driving without a trailer.
The vehicle/trailer combination:
R is heavier
R is restricted in its acceleration and gradi-
ent-climbing capability
R has an increased braking distance
R is affected more by strong crosswinds
R demands more sensitive steering
R consumes more fuel
On long and steep downhill gradients, you
must select a lower gear in good time, or in
vehicles with AUTOTRONIC*, select shift
range 1,2or 3. i
This also applies if you have activated
cruise control* or Speedtronic*.
This will use the braking effect of the engine,
so less braking will be required to maintain
the speed. This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly. If you need
additional braking, depress the brake pedal
repeatedly rather than continuously. G
Risk of accident
Never depress the brake pedal continu-
ously while the vehicle is in motion, e.g.
never cause the brakes to rub by applying
constant slight pedal pressure. This causes
the brake system to overheat, increases
the braking distance and can lead to the
brakes failing completely.
Driving tips
R Maintain a greater distance from the vehi-
cle in front than when driving without a
trailer.
R Avoid braking abruptly. If possible, brake
gently at first to allow the trailer to run on.
Then increase the braking force rapidly.
R The values given for gradient-climbing
capabilities from a standstill refer to sea
level. When driving in mountainous areas, 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
196
i
The cover cannot be removed.
Cleaning the exhaust tail pipes Dirt combined with the effects of road grit and
corrosive environmental factors may cause
flash rust to form on the surface.
Regular care of the exhaust tail pipes will
ensure that their original shine is restored.
! Do not clean the exhaust tail pipes with
alkaline-based cleaning agents such as
wheel cleaner.
Use the chrome-cleaning agent recommen-
ded by Mercedes-Benz for cleaning. Infor-
mation about chrome-cleaning agents can
be obtained from any Mercedes-Benz
Service Centre. Cleaning Parktronic* The sensors are located in the front and rear
bumpers.
1
Parktronic* sensors in the left-hand side
of the front bumper.
X Clean sensors 1in the bumper with water,
car shampoo and a soft cloth.
! Do not use dry, coarse or hard cloths and
do not scrub. You will otherwise scratch or
damage the sensors. If you intend to use a
high-pressure cleaner or a steam cleaner to
clean the sensors, observe the instructions
issued by the equipment manufacturer
concerning the distance to be maintained
between the nozzle of the high-pressure
cleaner and the vehicle. Trailer coupling*
The ball coupling must be cleaned if it
becomes dirty or corroded.
X Remove any rust using a wire brush.
X Remove dirt with a clean, lint-free cloth or
a brush.
! Do not clean the ball coupling with a high-
pressure cleaner. Do not use solvents. 1
Locking balls
2 Guide pin
3 Guide faces
4 Release lever
5 Ball neck head Operation
* optional
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Care
197
X
Lightly oil or grease positions 1to5 and
the ball coupling recess of the vehicle after
cleaning.
X Treat the lock with an oil that is acid and
resin-free.
X Check that the vehicle's trailer coupling is
working properly.
! Observe the note on care provided by the
trailer manufacturer.
i Maintenance of the ball coupling and
trailer coupling can also be performed by
any Mercedes-Benz Service Centre. H
Environmental note
Dispose of oily and greasy cloths in an envi-
ronmentally-responsible manner. Operation
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Display
messages 216 Display messages Possible cause/consequence Possible solution
. Cornering light
left
or
Cornering light
right The left-hand or right-hand cornering
light* is faulty. X
Change the bulb (Y page 244). . Dipped-beam left
or
Dipped-beam right Vehicles with the light and visibility pack-
age*: the left-hand or right-hand dipped-
beam headlamp is faulty. X
Halogen headlamp: replace the bulbs
(Y page 244).
X Bi-xenon headlamp*: visit a qualified special-
ist workshop. . Active light func-
tion currently
inoperative
The active light function* is faulty. X
Visit a qualified specialist workshop. . AUTO lights inop-
erative The light sensor is faulty. The constant
headlamp mode (daytime driving lights) is
switched on. X
Switch the lights to manual control in the on-
board computer (Y page 108).
X Switch the lights on and off using the light
switch. . Trailer turn sig-
nal left
or
Trailer turn sig-
nal right The left-hand or right-hand trailer turn sig-
nal lamp is faulty. X
Change the bulb. Practical advi
ce
* optional
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