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G
WARNING
If the ball coupling is not correctly installed
and secured, it could come loose while driving and endanger other road users. There is a risk
of an accident and injury.
Install and secure the ball coupling as descri-
bed in the ball coupling manufacturer's instal- lation instructions. Make sure that the ball
coupling is correctly installed and secured
before every journey. Coupling up a trailer
Observe the maximum permissible trailer
dimensions (width and length).
Most U.S. states and all Canadian provinces
require by law: R safety chains between the towing vehicle
and the trailer. The chains should be cross-
wound under the trailer drawbar. They must be fastened to the vehicle's trailer cou-
pling, not to the bumper or the axle.
Leave enough play in the chains to make
tight cornering possible.
R a separate brake system for certain types
of trailer.
R a safety switch for braked trailers. Check
the specific legal requirements applicable
to your state.
If the trailer detaches from the towing vehi-
cle, the safety switch applies the trailer's
brakes.
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system
of the towing vehicle, as the latter is equip-
ped with an anti-lock brake system. Doing
so will result in a loss of function of the
brake systems of both the vehicle and the
trailer.
i The vehicle's wiring harness features a
connection to the brake indicator lamp. 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 Couple up the trailer.
X Establish all electrical connections. Towing a trailer
There are numerous legal requirements con-
cerning the towing of a trailer, e.g. speed
restrictions. Make sure that your car/trailer
combination complies with the local regula-
tions:
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 charac-
teristics, 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. Towing a trailer
215Driving and parking Z
Page 218 of 386

R
When you couple up a trailer, check at reg-
ular 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 driv-
ing 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. Thenincrease 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 dra-
matically while the air-conditioning system
is switched on, switch off the air-condition-
ing 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. 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 rebound- ing 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 add-
ing 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" (Y
page 381).
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 val-
ues on the type plates of your vehicle and
the trailer. When calculating how much
weight the vehicle and trailer may carry, 216
Towing a trailerDriving and parking
Page 219 of 386

pay attention to the respective lowest val-
ues.
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 per-
missible gross weight.
i The weight of other accessories, passen-
gers 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 max-
imum permissible values, have the vehicle/ trailer combination (towing vehicle includ-
ing driver, passenger, load and fully laden
trailer) weighed on a calibrated weigh-
bridge.
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 cou-
pling recess.
X Make sure that the protective cap is firmly
in place. 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 max-
imum power consumption of 240 W to 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 386
Page 221 of 386
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 386

Useful information
i This Operator's Manual describes all
models and all standard and optional equip- ment 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 special-
ist workshops (Y page 27). Important safety notes
G
WARNING
If you operate information systems and com-
munication equipment integrated in the vehi- cle 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 equip-
ment when the vehicle is stationary.
You must observe the legal requirements for
the country in which you are currently driving when operating the on-board computer. G
WARNING
If the instrument cluster has failed or mal-
functioned, 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 immedi-
ately.
The on-board computer only shows messages
or warnings from certain systems in the mul- tifunction display. You should therefore make
sure your vehicle is operating safely at all times. Otherwise, a vehicle that is not oper-
ating safely may cause an accident.
If the operating safety of your vehicle is
impaired, park the vehicle safely as soon as
possible. Contact a qualified specialist work-
shop.
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 over-
heated 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 tem-
perature 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 386

Outside temperature display
You should pay special attention to road con-
ditions when temperatures are around freez-
ing point.
Bear in mind that the outside temperature
display indicates the temperature measured
and does not record the road temperature.
The outside temperature display is in the mul- tifunction display (Y page 222).
Changes in the outside temperature are dis-
played after a short delay. Speedometer with segments
The segments in the speedometer indicate
which speed range is available.
R Cruise control activated (Y page 175):
The segments light up from the stored
speed to the maximum speed.
R DISTRONIC PLUS activated (Y page 176):
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 386

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 mem-
ory 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 oper-
ating instructions
R Hides display messages/calls
up the last Trip
Trip menu 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 mes-
sages are shown in the multifunction display. 0043
Text field
0044 Menu bar
0087 Drive program (Y page 157)
0085 Transmission position (Y page 157)
0083 Time
0084 Permanent display: outside temperature
or speed (Y page 231)
X To show menu bar 0044:press the 0059
or 0065 button on the steering wheel.
Menu bar 0044disappears after a few seconds.
Text field 0043shows the selected menu or
submenu as well as display messages. 222
Displays and operationOn-board computer and displays