MERCEDES-BENZ M-Class 2015 W166 Owner's Manual

Ball coupling recess
Holes in the ball coupling and ball coupling recess
X Insert the ball coupling horizontally into ball
coupling recess 0044in the direction of the
arrow until the holes in ball coupling 0087are
in line with the holes in ball coupling
recess 0085. Bolt
X Slide bolt 0083into the hole in the ball cou-
pling recess and the ball coupling to the
stop. Bolt and spring cotter
X Secure the bolt using spring cotter 0084. Correctly installed and secured ball coupling
X Check the ball coupling, bolt and spring
cotter for correct installation.
If the ball coupling cannot be correctly moun-
ted, remove the ball coupling. Under these
circumstances, the ball coupling must not be used for trailer towing.
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 installed (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 cannot be guaran-
teed.
Have the entire trailer tow hitch checked at aqualified specialist workshop. Coupling up a trailer
! Do not connect the trailer's brake system
(if featured) to the hydraulic brake system Towing a trailer
259Driving and parking Z

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.
X Make sure that the automatic transmission
is set to position P.
X Apply the vehicle's electric parking brake.
X Start the engine.
X Vehicles with the AIRMATIC package:
select highway level.
X Vehicles with ADS: set ADS toAUTOor
COMF.
X Switch off the engine.
X Close all doors and the tailgate.
X Couple up the trailer.
X Establish all electrical connections.
X Check that the trailer lighting system is
working.
i Vehicles with the AIRMATIC package:
with a trailer attached, the vehicle will
always remain at highway level. When cou-
pling up a trailer, please observe the fol-
lowing:
R Unless highway level has been set man-
ually, the vehicle is automatically low-
ered to highway level. This is the case if a
speed of 5 mph (8 km/h) is reached.
R High-speed level is not available.
These restrictions apply to all accessories
powered through a connection to the trailer power socket of your vehicle, e.g. a bicycle
carrier.
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. 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:
- trailer tow hitch
- safety switch for braked trailers
- safety chains
- electrical connections
- lights
- 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 260
Towing a trailerDriving and parking

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 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, do not brake suddenly, but
instead depress the brake pedal moder-
ately at first so that the trailer can activate its 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 dra-
matically while the air-conditioning system
is switched on, switch off the air-condition-
ing system.
Coolant heat can also be dissipated by
opening the windows and switching the ventilation blower and the interior temper-
ature to the highest level.
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. G
WARNING
Vehicles with level control:
The vehicle is lowered as soon as you discon-
nect the trailer cable. This could result in your limbs or those of other people that are
between the vehicle body and tires or under-
neath the vehicle being trapped. There is a
risk of injury.
Make sure that nobody is in the immediate
vicinity of the wheel housings or under the
vehicle when you disconnect the trailer cable.
! 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 electric parking brake.
X Start the engine.
X Close all doors and the tailgate.
X Apply the trailer's parking brake. Towing a trailer
261Driving and parking Z

X
Detach the trailer cable and decouple the
trailer.
X Switch off the engine. Permissible trailer loads and drawbar
loads
Weight specifications Maximum permissible gross vehicle
weight rating
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 459).
Permissible noseweight
You will find installing dimensions and loads
under "Technical data" (Y page 459).
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,
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 additional accessories, pas-
sengers, and cargo reduces the permissi-
ble trailer load and drawbar load for your
vehicle.
Checking the vehicle and trailer weight R
To check that the weights of the towing
vehicle and the trailer comply with the max-
imum permissible values, have the vehicle/
trailer combination (including the driver,
passengers, and cargo with a 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 Remove the spring cotter.
X Remove the bolt from the ball coupling
recess.
X Remove the ball coupling from the ball cou-
pling recess.
X Clean the ball coupling if it is dirty.
X Stow the ball coupling so that it cannot be
thrown around.
Observe the loading guidelines (Y page 334)
and the safety notes regarding stowage
spaces (Y page 335).
Information on cleaning and care of the trailer tow hitch can be found at (Y page 376). 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: 262
Towing a trailerDriving an
d parking

R
brake sharply
R change direction suddenly
R are involved in an accident Trailer power supply
! 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 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.
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
263Driving and parking Z

264

Useful information
............................266
Important safety notes ....................266
Displays and operation ....................266
Menus and submenus ......................269
Display messages ............................. 284
Warning and indicator lamps in the instrument cluster ............................318 265On-board computer and displays

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 29). 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. 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.
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 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.
For an overview, see the instrument panel
illustration (Y
page 35). Displays and operation
Instrument cluster lighting
The lighting in the instrument cluster, in the
displays and the controls in the vehicle inte-
rior can be adjusted using the brightness con-
trol knob.
The brightness control knob is located on the bottom left of the instrument cluster
(Y page 35).
X Turn the brightness control knob clockwise
or counter-clockwise.
If the light switch is set to 0058,0060or
0058, the brightness is dependent upon
the brightness of the ambient light.
i The light sensor in the instrument cluster
automatically controls the brightness of
the multifunction display.
In daylight, the displays in the instrument
cluster are not illuminated. 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.
! 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. 266
Displays and operationOn-board computer and displays

The coolant temperature gauge is in the
instrument cluster on the right-hand side
(Y page 35).
Under normal operating conditions and with
the specified coolant level, the coolant tem-
perature may rise to 248 ‡ (120 †). Tachometer
! Do not drive in the overrevving range, as
this could damage the engine.
The red band in the tachometer indicates the
engine's overrevving range.
The fuel supply is interrupted to protect the
engine when the red band is reached. 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 268).
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 195):
The segments light up from the stored
speed to the maximum speed.
R DISTRONIC PLUS activated (Y page 198):
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 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
X To activate the on-board computer: 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. Displays and operation
267On-board computer and displays Z

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 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 if the phone book 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 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
0043
Time
0044 Permanent display: outside temperature
or speed (Y page 277)
0087 Text field
0085 Menu bar 268
Displays and operationOn-board computer and displays