2015 MERCEDES-BENZ M-Class trailer hitch

If a lane-correcting brake application occurs,
display 0043appears in the multifunction dis-
play.
If you leave your lane, under certain circum-
stances the vehicle will brake briefly on one
side. This is meant to assist you in bringing
the vehicle back to the original lane.
This function is available in the range between
40 mph and 120 mph (60 km/h and
200 km/h).
A lane-correcting brake application can only
be made after driving over a solid, recogniz-
able lane marking. Before this, a warning
must be given by means of intermittent vibra-
tion in the steering wheel. In addition, a lane
with lane markings on both sides must be
recognized. The brake application also
slightly reduces vehicle speed.
i A further lane-correcting brake applica-
tion can only occur after your vehicle has
returned to the original lane.
No lane-correcting brake application occurs
if:
R you clearly and actively steer, brake or
accelerate.
R you cut the corner on a sharp bend.
R you have switched on the turn signal.
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R you have adopted a sporty driving style with
high cornering speeds or high rates of
acceleration.
R ESP ®
is switched off. R
the transmission is not in position D.
R on vehicles with a trailer tow hitch, the
electrical connection to the trailer has been
correctly established.
R the off-road program is activated (vehicles
without the ON&OFFROAD package).
R off-road program 1 or 2 is activated (vehi-
cles with the ON&OFFROAD package).
R the LOW RANGE off-road gear is activated
(vehicles with the ON&OFFROAD package).
R a loss of tire pressure or a defective tire has
been detected and displayed.
Active Lane Keeping Assist does not detect
traffic situations or road users. An inappro-
priate brake application may be interrupted at
any time if you:
R steer slightly in the opposite direction
R switch on the turn signal
R clearly brake or accelerate
A lane-correcting brake application is inter-
rupted automatically if:
R a driving safety system intervenes, e.g.
ESP ®
, PRE-SAFE ®
Brake or Active Blind
Spot Assist.
R lane markings can no longer be recognized.
Switching on Active Lane Keeping Assist
X Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard
Standard orAdaptive Adaptive (Ypage 276).
If you drive at speeds above 40 mph
(60 km/h) and lane markings are detected, the lines in the assistance graphics display(Y page 275) are shown in green. Lane
Keeping Assist is ready for use.
When Standard Standard is selected, no warning
vibration occurs if:
R you switch on the turn signals. In this
event, the warnings are suppressed for a
certain period of time.
R a driving safety system intervenes, such
as ABS, BAS or ESP ®
.
When Adaptive Adaptive is selected, no warning
vibration occurs if: 246
Driving systemsDriving and parking

R
uphill or downhill gradient in percentage
R on-road/off-road program selected
R condition of the differential lock for the
transfer case
R the LOW RANGE off-road gear is selected
R condition of the LOW RANGE off-road
gear
R the on-road trailer program is selected Towing a trailer
Important safety notes
G
WARNING
Installing an unsuitable ball coupling may
result in overloading of the trailer tow hitch
and the rear axle. This applies especially if the ball coupling in question is longer or angled
differently. This could seriously impair the
driving characteristics and the trailer can
come loose. There is a risk of an accident.
You should only ever install a ball coupling
that has the permissible dimensions and that
is designed to meet your trailer-towing
requirements. Do not modify the ball coupling
or the trailer tow hitch.
You will find the values approved by the man-
ufacturer on the vehicle identification plates
and those for the towing vehicle under "Tech- nical data" (Y page 460). G
WARNING
If the ball coupling is not installed correctly or not secured with the bolt provided and the
corresponding spring cotter, the trailer may
come loose. There is a risk of an accident.
Always install and secure the ball coupling as
described. Before every journey, ensure that
the ball coupling is secured with the bolt and
the corresponding spring cotter. G
WARNING
If you rest your foot on the brake pedal while
driving, the braking system can overheat. This increases the stopping distance and can even cause the braking system to fail. There is a
risk of an accident.
Never use the brake pedal as a footrest. Never
depress the brake pedal and the accelerator
pedal at the same time. G
WARNING
When the vehicle/trailer combination begins
to lurch, you could lose control of it. The vehi- cle/trailer combination could even rollover.
There is a risk of an accident.
On no account should you attempt to
straighten up the vehicle/trailer combination
by increasing the speed. Reduce vehicle
speed and do not countersteer. Apply the
brake as necessary.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
Please observe the manufacturer's operating instructions for the trailer coupling if a
detachable trailer coupling is used.
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 permissible trailer drawbar noseweight
R the permissible trailer load
R the permissible rear axle load of the towing
vehicle
R the maximum permissible gross vehicle
weight of both the towing vehicle and the
trailer
The applicable permissible values, which
must not be exceeded, can be found:
R in the vehicle documents
R on the identification plates for the trailer
tow hitch and the trailer
R on the vehicle identification plate
If the values differ, the lowest value applies. 256
Towing a trailerDriving and pa
rking

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

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

Display messages
Possible causes/consequences and
0050
0050Solutions 0049
Check Front Left Check Front Left
Parking Lamp Parking Lamp
or
Check Front Right
Check Front Right
Parking Lamp Parking Lamp The front left or front right parking or standing lamp is defective.
X Check whether you are permitted to replace the bulb yourself
(Y page 129).
or
X Visit a qualified specialist workshop. 0049
Backup Light Backup Light The backup lamp is defective.
X Visit a qualified specialist workshop. 0049
Check Front Left Check Front Left
Sidemarker Lamp Sidemarker Lamp
or
Check Front Right
Check Front Right
Sidemarker Lamp Sidemarker Lamp The left or right front side marker lamp is defective.
X Visit a qualified specialist workshop. 0049
Check Left Tail Check Left Tail
Lamp Lamp
orCheck
Check
Right Tail Lamp
Right Tail Lamp The left or right-hand tail lamp is defective.
or
The rear left or right side marker lamp is defective.
X Visit a qualified specialist workshop. 0049
Check Check
Left
LeftDaytime
Daytime
Running Light
Running Light or
Check Right Day‐
Check Right Day‐
time Running Light time Running Light The left-hand or right-hand daytime running lamp is faulty.
X Visit a qualified specialist workshop. 0049
Active Light Sys‐ Active Light Sys‐
tem Inoperative tem Inoperative The active light function is defective.
X Visit a qualified specialist workshop. 0049
Malfunction See Malfunction See
Operator's Manual Operator's Manual The exterior lighting is defective.
X Visit a qualified specialist workshop. Vehicles with trailer tow hitch: a fuse may have blown.
X Check the fuses (Y page 396).
X If necessary, replace the blown fuse. Observe the warning notes.
If the display message continues to be displayed: X Visit a qualified specialist workshop. Display
messages
299On-board computer and displays Z

the vehicle and the power washer nozzle.
Information about the correct distance is
available from the equipment manufac-
turer. X
Clean sensors 0043of the driving systems
with water, car shampoo and a soft cloth.
Cleaning the rear view camera !
Do not clean the camera lens and the area
around the rear view camera with a power
washer. X
Use clear water and a soft cloth to clean
camera lens 0043.
Cleaning the 360° camera !
Do not clean the camera lens and the area
around the 360° camera with a power
washer.360 X
Use clear water and a soft cloth to clean
camera lens 0043.
Cleaning the exhaust pipe G
WARNING
The exhaust tail pipe and tail pipe trim can
become very hot. If you come into contact
with these parts of the vehicle, you could burn
yourself. There is a risk of injury.
Always be particularly careful around the
exhaust tail pipe and the tail pipe trim. Allow
these components to cool down before touch-
ing them.
! Do not clean the exhaust pipe with acid-
based cleaning agents such as sanitary
cleansers or wheel cleaners.
Impurities combined with the effects of road
grit and corrosive environmental factors may cause flash rust to form on the surface. You
can restore the original shine of the exhaust
pipe by cleaning it regularly, especially in win- ter and after washing.
X Clean the exhaust pipe with a chrome care
product tested and approved by Mercedes-
Benz.
Cleaning the trailer tow hitch H
Environmental note
Dispose of rags soaked in oil and grease in an environmentally responsible manner.
! Do not clean the ball coupling with a
power washer. Do not use solvents. 376
CareMaintenance and care

!
Please note the care instructions in the
trailer coupling manufacturer's operating
instructions. The ball coupling must be cleaned if it
becomes dirty or corroded.
X Remove rust on the ball of the ball coupling,
e.g. with a wire brush.
X Remove dirt with a clean, lint-free cloth or a
brush.
X After cleaning, lightly oil or grease ball cou-
pling 0043.
X Check that the vehicle's trailer tow hitch is
working properly.
i You can also have the maintenance work
on the ball coupling and the trailer tow hitch
carried out by a qualified specialist work-
shop. Interior care
Cleaning the display !
For cleaning, do not use any of the fol-
lowing:
R alcohol-based thinner or gasoline
R abrasive cleaning agents
R commercially-available household clean-
ing agents
These may damage the display surface. Do not put pressure on the display surface
when cleaning. This could lead to irrepara-
ble damage to the display. X
Before cleaning the display, make sure that
it is switched off and has cooled down.
X Clean the display surface using a commer-
cially available microfiber cloth and
TFT/LCD display cleaner.
X Dry the display surface using a dry micro-
fiber cloth.
Cleaning Night View Assist Plus !
Never clean the camera lens. When clean-
ing the field of vision of the driving systems, make sure that you do not spray glass
cleaner on the camera lens. If the camera
lens is dirty, visit a qualified specialist work-
shop. X
Fold down the camera cover by recess 0043. X
Use a soft cloth to clean the windshield in
front of camera 0044. Care
377Maintenance and care Z