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X
Couple up the trailer.
X Establish all electrical connections. Towing a trailer
There are numerous legal requirements
concerning the towing of a trailer, e.g. speed
restrictions. Make sure that your car/trailer
combination complies with the local
regulations:
R in your place of residence
R in the location to which you are driving
The police and local authorities can provide
reliable information.
Observe the following when towing a trailer:
R To gain driving experience and to become
accustomed to the new handling
characteristics, you should practice the
following in a traffic-free location:
- cornering
- stopping
- backing up
R Before driving, check:
-the trailer tow hitch
- the safety switch for braked trailers
- the safety chains
- electrical connections
- the lights
- the wheels
R Adjust the exterior mirrors to provide an
unobstructed view of the rear section of the
trailer.
R If the trailer has electronically controlled
brakes, pull away carefully. Brake manually
using the brake controller and check
whether the brakes function correctly.
R Secure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
R When you couple up a trailer, check at
regular intervals that the load is firmly
secured. If the trailer is equipped with trailer lights and brakes, check the trailer
to ensure that these are working.
R Bear in mind that the handling will be less
stable when towing a trailer than when
driving without one. Avoid sudden steering
movements.
R The vehicle/trailer combination is heavier,
accelerates more slowly, has a decreased
gradient climbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
R If possible, avoid abrupt braking. Depress
the brake pedal moderately at first, so that
the trailer can activate its own brakes. Then
increase the pressure on the brake pedal.
R If the automatic transmission repeatedly
shifts between gears on uphill or downhill
gradients, shift to a lower gear using the
left-hand steering wheel paddle shifter.
A lower gear and lower speed reduce the
risk of engine failure.
R When driving downhill, shift to a lower gear
to utilize the engine's braking effect.
Avoid continuous brake application as this
may overheat the vehicle brakes and, if
installed, the trailer brakes.
R If the coolant temperature increases
dramatically while the air-conditioning
system is switched on, switch off the air-
conditioning system.
Coolant heat can additionally be dissipated
by opening the windows and by setting the
blower fan and the interior temperature to
maximum.
R When overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination.
Due to the length of the vehicle/trailer
combination, you require additional road
space in relation to the vehicle you are
overtaking, before you can change back to
the original lane. Towing a trailer
215Driving and parking Z
Page 218 of 382

Decoupling a trailer
G
WARNING
If you uncouple a trailer with the overrun
brake engaged, you could trap your hand
between the vehicle and the trailer drawbar.
There is a risk of injury.
Do not uncouple a trailer if the overrun brake
is engaged.
! Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could be damaged by the
rebounding of the overrun brake.
X Make sure that the automatic transmission
is set to position P.
X Apply the vehicle's parking brake.
X Close all doors and the tailgate.
X Apply the trailer's parking brake.
X Remove the trailer cable and decouple the
trailer. Permissible trailer loads and drawbar
loads
Weight specifications The gross trailer weight is calculated by
adding the weight of the trailer to the weight
of the load and equipment on the trailer.
You will find installing dimensions and loads
under "Technical data" (
Ypage 376).
Loading a trailer R
When loading the trailer, make sure that
neither the permissible gross weight of the
trailer nor the gross vehicle weight is
exceeded. The permissible gross vehicle
weight is indicated on the identification
plate on the B-pillar on the driver's side of
the vehicle.
You can find the maximum permissible
values on the type plates of your vehicle
and the trailer. When calculating how much
weight the vehicle and trailer may carry, pay attention to the respective lowest
values.
R The trailer drawbar load on the ball coupling
must be added to the rear axle load to avoid
exceeding the permissible gross axle
weight. The permissible gross vehicle
weight is indicated on the identification
plate on the B-pillar on the driver's side of
the vehicle.
i Mercedes-Benz recommends a trailer
load where the trailer drawbar noseweight
accounts for 8% to 15% of the trailer's
permissible gross weight.
i The weight of other accessories,
passengers and loads reduces:
R the permissible trailer load
R the permissible noseweight that your
vehicle can tow
Checking the vehicle and trailer weight R
To ensure compliance of the weight of the
towing vehicle and the trailer with the
maximum permissible values, have the
vehicle/trailer combination (towing vehicle
including driver, passenger, load and fully
laden trailer) weighed on a calibrated
weighbridge.
R Check the gross axle weight rating of the
front and rear axles, the gross weight of the
trailer and trailer drawbar load. Removing the ball coupling
X Observe the manufacturer's installation
instructions.
X Press the protective cap into the ball
coupling recess.
X Make sure that the protective cap is firmly
in place. 216
Towing a trailerDriving and pa
rking
Page 219 of 382
Storing the ball coupling
G
WARNING
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
X Observe the manufacturer's installation
instructions. Trailer power supply
The trailer socket of your vehicle is equipped
at the factory with a permanent power supply.
The permanent power supply is supplied via
trailer socket pin 4.
! You can connect accessories with a
maximum power consumption of 240 Wto
the permanent power supply.
You must not charge a trailer battery using
the power supply.
The trailer's permanent power supply is
switched off in the event of low vehicle supply
voltage and after six hours at the latest.
A qualified specialist workshop can provide
more information about installing the trailer
electrics. Towing a trailer
217Driving and parking Z
Page 220 of 382
Page 221 of 382
Useful information
............................220
Important safety notes ....................220
Displays and operation ....................220
Menus and submenus ......................223
Display messages ............................. 235
Warning and indicator lamps in the
instrument cluster ............................261 219On-board computer and displays
Page 222 of 382

Useful information
i This Operator's Manual describes all
models and all standard and optional
equipment of your vehicle available at the
time of publication of the Operator's
Manual. Country-specific differences are
possible. Please note that your vehicle may
not be equipped with all features
described. This also applies to safety-
related systems and functions.
i Read the information on qualified
specialist workshops: (Y page 27).Important safety notes
G
WARNING
If you operate information systems and
communication equipment integrated in the
vehicle while driving, you will be distracted
from traffic conditions. You could also lose
control of the vehicle. There is a risk of an
accident.
Only operate the equipment when the traffic
situation permits. If you are not sure that this
is possible, park the vehicle paying attention
to traffic conditions and operate the
equipment when the vehicle is stationary. G
WARNING
If the instrument cluster has failed or
malfunctioned, you may not recognize
function restrictions in systems relevant to
safety. The operating safety of your vehicle
may be impaired. There is a risk of an
accident.
Drive on carefully. Have the vehicle checked
at a qualified specialist workshop
immediately.
You must observe the legal requirements for
the country in which you are currently driving
when operating the on-board computer.
The on-board computer only shows messages
or warnings from certain systems in the multifunction display. You should therefore
make sure your vehicle is operating safely at
all times. Otherwise, a vehicle that is not
operating safely may cause an accident.
For an overview, see the instrument panel
illustration (Y
page 33). Displays and operation
Coolant temperature display
G
WARNING
Opening the hood when the engine is
overheated or when there is a fire in the
engine compartment could expose you to hot
gases or other service products. There is a
risk of injury.
Let an overheated engine cool down before
opening the hood. If there is a fire in the
engine compartment, keep the hood closed
and contact the fire department.
The coolant temperature gauge is in the
instrument cluster on the left-hand side.
Under normal operating conditions and with
the specified coolant level, the coolant
temperature may rise to 248 ‡ (120 †).
! A display message is shown if the coolant
temperature is too high.
If the coolant temperature is over
248 ‡(120 †), do not continue driving. The
engine will otherwise be damaged. Tachometer
The red band in the tachometer indicates the
engine's overrevving range.
! Do not drive in the overrevving range, as
this could damage the engine.
The fuel supply is interrupted to protect the
engine when the red band is reached. 220
Displays and operationOn-board computer and displays
Page 223 of 382

Outside temperature display
You should pay special attention to road
conditions when temperatures are around
freezing point.
The outside temperature display is in the
multifunction display (Y page 222).
Changes in the outside temperature are
displayed after a short delay. Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
R Cruise control activated (Y page 173):
The segments light up from the stored
speed to the maximum speed.
R DISTRONIC PLUS activated (Y page 175):
One or two segments in the set speed
range light up.
R DISTRONIC PLUS detects a vehicle in front:
The segments between the speed of the
vehicle in front and the stored speed light
up. Operating the on-board computer
Overview The on-board computer is activated as soon
as you turn the SmartKey to position 1in the
ignition lock.
You can control the multifunction display and
the settings in the on-board computer using
the buttons on the multifunction steering
wheel. 0043
Multifunction display
0044 Switches on the Voice Control System;
see the separate operating instructions
0087 Right control panel
0085 Left control panel
0083 Back button
Left control panel 0059
0065 R
Calls up the menu and menu bar 0063
0064
Press briefly:
R
Scrolls in lists
R Selects a submenu or function
R In the Audio Audio menu: selects a
stored station, an audio track or
a video scene
R In the Tel Tel(telephone) menu:
switches to the phone book and
selects a name or telephone
number Displays and operation
221On-board computer and displays Z
Page 224 of 382

0063
0064
Press and hold:
R
In the Audio Audio menu: selects the
previous/next station or selects
an audio track or a video scene
using rapid scrolling
R In the Tel
Tel (Telephone) menu:
starts rapid scrolling of the
phone book if it is open 0076 R
Confirms a selection/display
message
R In the Tel Tel(Telephone) menu:
switches to the telephone book
and starts dialing the selected
number
R In the Audio Audio menu: stops the
station search function at the
desired station Right control panel
0076 R
Rejects or ends a call
R Exits phone book/redial
memory 0061 R
Makes or accepts a call
R Switches to the redial memory 0081
0082 R
Adjusts the volume 0063 R
Mute Back button
0038
Press briefly:
R
Back
R Switches off the Voice Control
System; see the separate
operating instructions
R Hides display messages/calls
up the last Trip Tripmenu function
used
R Exits the telephone book/redial
memory 0038
Press and hold:
R
Calls up the standard display in
the Trip Trip menu Multifunction display
Values and settings as well as display
messages are shown in the multifunction
display. 0043
Text field
0044 Menu bar
0087 Drive program (Y page 153)
0085 Transmission position (Y page 153)
0083 Time
0084 Permanent display: outside temperature
or speed (Y page 231)
X To show menu bar0044: press the0059
or 0065 button on the steering wheel.
Menu bar 0044disappears after a few seconds. 222
Displays and operationOn-board computer and displays