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...?
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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Where will I find...?
253
location of the jack and of the other tools
may differ from those illustrated.
Example
1
Tool holder
2 Wheel wrench
3 Electric air pump
4 Instructions on the installation position of
the tool holder
5 Fuse allocation chart
6 Jack, ratchet ring spanner
7 Centring pin
8 Folding wheel chock
9 Towing eye
a Wheel bolts
b Ball coupling of the trailer tow hitch*
c Emergency spare wheel* Removing the emergency spare wheel*
X
Remove the jack from the tool holder
(Y page 252). 1
Retaining screw
2 Emergency spare wheel*
3 Tool holder
X Turn retaining screw 1anticlockwise and
out of tool holder 3and remove it.
i If retaining screw 1does not come out
immediately, turn tool holder 3anticlock-
wise a little.
Retaining screw 1should then unscrew
with ease. X
Turn tool holder 3approximately 180°, so
that the electrical air pump points back-
wards (Y page 252).
X Remove tool holder 3from emergency
spare wheel* 2.
X Remove emergency spare wheel* 2from
the emergency spare wheel well.
Stowing the emergency spare wheel*
X Remove the warning triangle from the
emergency spare wheel well (Y page 250). 1
Guides
In the spare wheel well, there are two guides
1 to keep the emergency spare wheel* in
place. Practical advice
* optional
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Display
messages 267Display messages Possible cause/consequence Possible solution
> Vehicle rising
Wait briefly The vehicle level is too low. X
Do not pull away.
The rear axle level control* or AIRMATIC* has
not yet set the level required for driving.
X Wait until the display message disappears
before pulling away. > STOP car too low
G
Risk of accident
You have pulled away while the vehicle
level is still too low or the rear axle level
control* or AIRMATIC* is faulty. The rear axle level control* or AIRMATIC* should
set the vehicle to the selected level after a short
period. While the message is displayed:
X Avoid large steering angles. Otherwise, the
front wing or the tyres could be damaged when
you drive on. Listen for scraping sounds.
X Do not exceed a maximum speed of 80 km/h.
If the display message does not disappear:
X Have the vehicle checked at a qualified spe-
cialist workshop. > Level selection
not permitted You cannot change the vehicle level. Pos-
sible causes:
R
Vehicles with AIRMATIC*: you are
exceeding the speed permissible for the
selected vehicle level.
R You are towing a trailer.
R The socket of the trailer coupling is
being used, for example, by a cycle
rack. X
Vehicles with AIRMATIC*: drive slower and
reselect the desired vehicle level.
X Observe the notes on trailer towing
(Y page 239). Practical advi
ce
* optional
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Troubleshooting
299Problem Possible cause/consequence Suggested solutions
The vehicle cannot be started
using the KEYLESS GO key and
the KEYLESS GO button. The KEY-
LESS GO key is in the vehicle. A door is open. The key can there-
fore not be detected as easily. X
Close the door and try to start the vehicle again. You did not depress the brake
when starting the engine. X
Depress the brake and press the KEYLESS GO button. There is interference from a pow-
erful source of radio waves. X
Start your vehicle using the KEYLESS GO key in the ignition lock. You have lost the KEYLESS GO
key. X
Have the KEYLESS GO key cancelled at a Mercedes-Benz Service
Centre.
X Report the loss immediately to the vehicle insurers.
X If necessary, have the manual locks changed too. Trailer towing*
Problem Possible cause/consequence Suggested solutions
The ball coupling cannot be
locked.
The key cannot be removed from
the ball coupling. G
Risk of accident
The ball coupling is dirty.
The trailer coupling is damaged. X
Remove the ball coupling and clean it (Y page 248). If the ball cou-
pling still cannot be locked, remove the ball coupling. It must no
longer be used to tow a trailer, as safe operation is not guaranteed.
X Have the entire trailer coupling checked at a qualified specialist
workshop. Practical advice
* optional
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