tow MERCEDES-BENZ R-CLASS MPV 2008 Repair Manual

Trailer towing*
235Driving abroad
Points to remember
An extensive Mercedes-Benz Service network
is also available in other countries. The
Service Hotline's current telephone numbers
for use when you are abroad are to be found
in the "Service24h" chapter of the Service
Booklet.
Only low-octane fuel is available in certain
countries.
You can find further information about fuel
grades on (Y page 218). Symmetrical dipped beam
If your journey takes you to countries where
vehicles are driven on the opposite side of the
road to the country in which the vehicle is
registered, your headlamps must be switched
to symmetrical dipped beam. Oncoming traf-
fic will be dazzled less.
X Have the headlamps switched over at a
qualified specialist workshop, e. g. a
Mercedes-Benz Service Centre. G
Risk of accident
Have your headlamps switched back to
asymmetrical dipped beam if you visit a country in which traffic drives on the same
side of the road as in the country in which
your vehicle was registered. You may oth-
erwise dazzle the oncoming traffic and
could cause an accident. Trailer towing*
Fitting the ball coupling
Before you can tow a trailer with your vehicle,
you must fit the ball coupling.
There is a key for the ball coupling.
X Make a note of the key number.
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 fitted, the vehicle/trailer
combination will not be properly secured
and may detach. This could cause an acci-
dent. Fit the ball coupling carefully and
make sure that it engages correctly.
The detachable ball coupling is located in the
stowage well under the luggage compartment
floor.
The ball coupling recess is behind the cover
at the bottom of the bumper. Operation
* optional
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Trailer towing*
2361
Cover
X Remove cover 1.
X Take the ball coupling and the key from the
stowage well under the luggage compart-
ment floor ( Ypage 250). 1
Protective cap X
Pull protective cap 1underneath the
bumper vertically downwards in the direc-
tion of the arrow and out of the ball coupling
recess.
X Place protective cap 1in the stowage well
under the luggage compartment floor. 1
Key
2 Protective cap
X Pull protective cap 2off the lock in the
handwheel.
X Insert key 1into the lock in the hand-
wheel.
X Turn key 1anti-clockwise.
i The key remains inserted when you
remove the ball coupling. 3
Ball coupling recess
4 Handwheel
X Pull handwheel 4away from the ball cou-
pling in the direction of the arrow and turn
it clockwise until it engages.
The white dot on the ball coupling is aligned
with the red area on the handwheel.
X Insert the ball coupling vertically up into
ball coupling recess 3in the direction of
the arrow until it engages. Operation
* optional
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Trailer towing*
2371
Key
2 Protective cap
5 Green area on the handwheel
6 White dot on the ball coupling
X Handwheel 4turns automatically, aligning
green area 5on handwheel 4with white
dot 6on the ball coupling.
X Turn key 1to the stop in the direction of
the arrow (lock).
X Remove key 1.
X Press protective cap 2onto the lock. G
Risk of accident
The ball coupling is only securely mounted
when the green area on the handwheel is
aligned with the white dot 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 tow hitch must
then not be used to tow a trailer, as safe
operation is not guaranteed.
Have the entire trailer tow hitch 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. 1
Socket Coupling up and uncoupling a trailer
Coupling up a trailer Steel-spring vehicles
X
Make sure the selector lever is set to P.
X Depress the parking 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. Operation
* optional
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Trailer towing*
238
Vehicles with rear axle level control* G
Risk of injury
Never lock, unlock, open or close a vehicle
door or tailgate when coupling up or decou-
pling a trailer. The vehicle level could
change and you could endanger yourself or
others.
Never press the ADS button* or operate the
level control* while you are coupling up or
decoupling a trailer.
X Make sure the selector lever is set to P.
X Depress the parking brake.
X Close the doors and tailgate.
X Position the trailer level behind the vehicle.
X Couple up the trailer.
X Establish the electrical connection
between the vehicle and the trailer.
X Start the engine.
Vehicles with the AIRMATIC package* G
Risk of injury
Never lock, unlock, open or close a vehicle
door or tailgate when coupling up or decou-
pling a trailer. The vehicle level could
change and you could endanger yourself or
others. Never press the ADS button* or operate the
level control* while you are coupling up or
decoupling a trailer.
X Make sure the selector lever is set to P.
X Depress the parking brake.
X Start the engine.
X Set the vehicle to highway level
(Y page 152).
X Switch off the engine.
X Close the doors and tailgate.
X Position the trailer level behind the vehicle.
X Couple up the trailer.
X Establish the electrical connection
between the vehicle and the trailer.
i If you have coupled a trailer, the vehicle
will remain at highway level.
The vehicle automatically lowers to high-
way level if you drive faster than 8 km/h
with a trailer. The vehicle is not lowered to
the high-speed level even if you are travel-
ling at higher speeds.
This also applies when using accessories
that are plugged into the socket of the
trailer coupling (e.g. a bicycle rack). Decoupling a trailer G
Risk of injury
Do not connect a trailer with an engaged
overrun brake. Otherwise, your hand could
become trapped between the bumper and
drawbar.
! Do not uncouple a trailer with overrun
brake between the bumper and drawbar,
otherwise your vehicle could be damaged
by the spring action of the overrun brake.
Steel-spring vehicles
X Make sure the selector lever is set to P.
X Depress the parking brake.
X Secure the trailer against rolling away.
X Remove the trailer cable and decouple the
trailer.
Vehicles with rear axle level control*
X Make sure the selector lever is set to P.
X Depress the parking brake.
X Start the engine.
X Close the doors and tailgate.
X Secure the trailer against rolling away.
X Remove the trailer cable. Operation
* optional
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Trailer towing*
239G
Risk of injury
As soon as you raise the trailer drawbar, the
unladen vehicle rises slightly. The vehicle
then lowers to driving level.
Make sure that nobody is in the vicinity of
the wheel arch or the underbody. You could
otherwise trap yourself or others.
X Lift up the trailer drawbar and decouple the
trailer.
X Switch off the engine.
Vehicles with the AIRMATIC package*
X Make sure the selector lever is set to P.
X Depress the parking brake.
X Start the engine.
X Close the doors and tailgate.
X Secure the trailer against rolling away. G
Risk of injury
The vehicle is lowered as soon as you dis-
connect the trailer cable. Make sure that
nobody is in the vicinity of the wheel arch
or the underbody. You could otherwise trap
yourself or others.
As soon as you decouple the trailer, the
unladen vehicle rises slightly. Make sure that you or others are not injured in the
process.
X Remove the trailer cable and decouple the
trailer.
X Switch off the engine. 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 permitted trailer drawbar nose-
weight
R The permitted trailer load R
The permitted rear axle load of the towing
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 354).
The maximum permissible trailer drawbar
noseweight on the ball coupling is 85 kg.
However, the actual noseweight 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
not use a noseweight of less than 50 kg,
otherwise the trailer may come loose. Operation
* optional
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Trailer towing*
240Bear in mind that the payload and the rear
axle load are reduced by the actual nose-
weight.
i On vehicles without level control, the
height of the ball coupling will alter accord-
ing to the load placed on the vehicle. In this
case, you should use a trailer with a height-
adjustable drawbar.
Driving tips i
Observe the notes on ESP ®
trailer stabi-
lisation (Y page 60).
In Germany, the maximum permitted speed
for vehicle/trailer combinations is 80 km/h.
! A maximum speed of 80 km/h should not
be exceeded, even in countries where
higher speeds are permitted for vehicle/
trailer combinations.
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 the shift range 1,2or 3in good
time.
i This also applies if you have activated
cruise control, Distronic* or Speedtronic.
This uses the braking effect of the engine and
you will not have to brake to such an extent
to maintain the same speed. This relieves the
load on the brake system and prevents the
brakes from overheating 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,
note 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. Operation
* optional
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Trailer towing*
241Removing the ball coupling
X Pull the protective cap off the lock in the
handwheel.
X Use the key to unlock the lock in the hand-
wheel.
X Hold the ball coupling. Pull the handwheel
away from the ball coupling and turn it
clockwise until it engages.
The red area on the handwheel is aligned
with the white dot on the ball coupling.
X Pull out the ball coupling downwards.
X Clean the ball coupling if it is dirty.
X Press the protective cap into the ball cou-
pling recess until it engages.
X Make sure that the protective cap is firmly
seated.
X Replace the cover.
Storing the ball coupling X
Place the ball coupling with the key inser-
ted in the ball coupling stowage compart-
ment in the stowage well under the luggage
compartment floor. 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
Information on cleaning and care of the trailer
coupling can be found at (Y page 248). 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. You can obtain further information about
installing the trailer electrics from a qualified
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. Operation
* optional
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249
Where will I find...?
...........................250
Display messages ............................. 255
Troubleshooting ................................ 278
Locking/unlocking in an emer-
gency ................................................. 302
Resetting triggered NECK-PRO
head restraints .................................. 304
Changing the batteries .....................304
Changing the bulbs ...........................306
Replacing the wiper blades ..............311
Flat tyre ............................................. 313
Battery ............................................... 323
Jump-starting .................................... 329
Towing and tow-starting ..................330
Fuses .................................................. 333 Practical advice
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Where will I find...?
250 Where will I find...?
Warning triangle
The warning triangle is located in the stowage
space under the luggage compartment floor. 1
Luggage compartment floor
2 Release handle
X Pull release handle 2.
X Fold luggage compartment floor 1
upwards. Vehicles with a TIREFIT kit Example
1
Warning triangle 29
X Remove warning triangle 1.Vehicles with an emergency spare
wheel* Example
1
Warning triangle
X Remove warning triangle 1.
29 Depending on the date of production of the vehicle, the stowage location of the warning triangle may differ from that illustrated. Practical advice
* optional
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Where will I find...?
252 Vehicle tool kit, jack, TIREFIT kit and
emergency spare wheel*
The vehicle tool kit, jack, TIREFIT kit and
emergency spare wheel* are in the stowage
compartment under the luggage compart-
ment floor. G
Risk of injury
The jack is designed only to raise and hold
the vehicle for a short time while a wheel
is being changed.
You must use stands if you are carrying out
work on the vehicle.
Make sure that the jack is placed on a firm,
non-slip and level surface. Do not use
wooden blocks or similar objects as a jack
underlay. Otherwise, the jack will not be
able to achieve its load-bearing capacity
due to the restricted height.
Do not start the engine at any time while a
wheel is being changed.
Do not lie under the vehicle when it is being
supported by the jack. If you do not raise
the vehicle as described, it could slip off the
jack (e.g. if the engine is started or a door
or the tailgate is opened or closed) and you
could be seriously injured. X
Open the tailgate.
X Open the luggage compartment floor
(Y page 250).
! If the luggage compartment cover* is fit-
ted, roll it open fully.
Only for luggage compartment covers* fit-
ted behind the 3rd row of seats:
Fold forwards the section of the luggage
compartment cover* that is still protrud-
ing. Otherwise the strap of the retaining
hook may damage the luggage compart-
ment cover*.
Vehicles with a TIREFIT kit i
Depending on the date of production of
the vehicle, the appearance and stowage
location of the jack and of the other tools
may differ from those illustrated. Example
1
Ball coupling of the trailer tow hitch*
2 Folding wheel chock
3 Jack, ratchet ring spanner
4 TIREFIT kit 30
5 Electric air pump 30
6 Fuse allocation chart
7 Wheel wrench
8 Towing eye
9 Centring pin
Vehicles with an emergency spare
wheel* i
Depending on the date of production of
the vehicle, the appearance and stowage
30 Not on vehicles with MOExtended run-flat system. Practical advice
* optional
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