2014 MERCEDES-BENZ GLK-CLASS SUV trailer

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

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

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

Safety systems
Display messages Possible causes/consequences and
M
MSolutions !÷
Currently Currently
Unavailable See Unavailable See
Operator's Manual Operator's Manual ABS (Anti-lock Braking System), ESP
®
(Electronic Stability
Program), BAS (Brake Assist), PRE-SAFE ®
, the HOLD function, hill
start assist and ESP ®
trailer stabilization are temporarily
unavailable.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷,åand! warning lamps light up in
the instrument cluster.
ATTENTION ASSIST is deactivated.
Possible causes are:
R self-diagnosis is not yet complete.
R the on-board voltage may be insufficient.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely
affected. The braking distance in an emergency braking situation
can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive a suitable distance, making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. ÷
Inoperative See Inoperative See
Operator's Manual Operator's Manual ESP
®
, BAS, PRE-SAFE ®
, the HOLD function, hill start assist and
ESP ®
trailer stabilization are unavailable due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷andå warning lamps light up in the
instrument cluster.
The self-diagnosis function might not be complete, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. 236
Display messagesOn-board computer and displays

Display messages Possible causes/consequences and
M
MSolutions The braking distance in an emergency braking situation can thus
increase.
If ESP
®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Carefully drive a suitable distance, making slight steering
movements at a speed above 12 mph (20 km/h).
If the display message disappears, the functions mentioned
above are available again.
If the display message continues to be displayed:
X Drive on carefully.
X Visit a qualified specialist workshop. T!
÷
Inoperative See Inoperative See
Operator's Manual Operator's Manual EBD (electronic brake force distribution), ABS, ESP
®
, BAS, PRE-
SAFE ®
, the HOLD function, hill start assist and ESP ®
trailer
stabilization are unavailable due to a malfunction.
BAS PLUS and PRE-SAFE ®
Brake may also have failed.
In addition, the ÷,åand! warning lamps light up in
the instrument cluster and a warning tone sounds.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The front and rear wheels could therefore
lock if you brake hard, for example.
The steerability and braking characteristics may be severely
affected. The braking distance in an emergency braking situation
can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Drive on carefully.
X Visit a qualified specialist workshop immediately. F(USA
only)
J(Canada
only)
Please Release Please Release
Parking Brake Parking Brake You are driving with the parking brake applied. A warning tone also
sounds.
X
Release the parking brake. Display
messages
237On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions X
Wait for a period of at least 60 seconds until the necessary
system checks have been completed.
X Make sure that the display messages do not appear in the
multifunction display.
If these conditions are fulfilled, the front-passenger seat can be
occupied again. Whether the PASSENGER AIR BAG OFF indicator
lamp remains lit or goes out depends on how OCS classifies the
occupant.
If the conditions are not fulfilled, the system is not operating
correctly.
X Visit a qualified specialist workshop immediately.
For further information about the Occupant Classification System,
see (Y page 49). Lights
i Display messages about LEDs:
This display message will only appear if all LEDs have failed. Display messages Possible causes/consequences and
M MSolutions b
Check Left Check Left
Cornering Cornering
Light Light
orCheck RightCheck Right
Cornering Light
Cornering Light The left or right-hand cornering light is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 119).
or
X Visit a qualified specialist workshop. b
Check Left Low Check Left Low
Beam BeamorCheck Right
Check Right
Low Beam
Low Beam The left or right-hand low-beam headlamp is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 119).
or
X Visit a qualified specialist workshop. b
Check Check
Trailer
Trailer Left
Left
Tail Lamp
Tail LamporCheck Check
Trailer
Trailer Right
RightTail
Tail
Lamp
Lamp The left or right-hand trailer tail lamp is faulty.
X
Observe the separate operating instructions provided by the
trailer manufacturer. Display
messages
243On-board computer and displays Z

Display messages Possible causes/consequences and
M
MSolutions b
Check Check
Trailer
Trailer Left
Left
Turn Signal
Turn Signal orCheckCheck
Trailer
Trailer Right
RightTurn
Turn
Signal
Signal The left or right-hand trailer turn signal lamp is defective.
X
Observe the separate operating instructions provided by the
trailer manufacturer. b
Check Trailer Check Trailer
Brake Lamp Brake Lamp The trailer brake lamp is defective.
X
Observe the separate operating instructions provided by the
trailer manufacturer. b
Check Rear Left Check Rear Left
Turn Signal Turn Signal
orCheckCheck
Rear Right Turn
Rear Right Turn
Signal Signal The rear left-hand or rear right-hand turn signal is defective.
X
Visit a qualified specialist workshop. b
Check Front Left Check Front Left
Turn Signal Turn Signal
orCheckCheck
Front Right Turn
Front Right Turn
Signal Signal The front left-hand or front right-hand turn signal is defective.
X
Check whether you are permitted to replace the bulb yourself
(Y page 119).
or
X Visit a qualified specialist workshop. b
Check Left Mirror Check Left Mirror
Turn Signal Turn Signal
orCheckCheck
Right Mirror Turn
Right Mirror Turn
Signal Signal The turn signal in the left-hand or right-hand exterior mirror is
defective.
X
Visit a qualified specialist workshop. b
Check Check
Center
Center Brake
Brake
Lamp
Lamp The high-mounted brake lamp is faulty.
X
Visit a qualified specialist workshop. b
Check Left Tail Check Left Tail
and Brake and Brake
Lamps Lamps
orCheck RightCheck Right
Tail and Brake
Tail and Brake
Lamps Lamps The left or right-hand tail lamp/brake lamp is defective.
X
Visit a qualified specialist workshop. 244
Display
messagesOn-board computer and displays

Safety systems
Problem Possible causes/consequences and
M
MSolutions $
(USA only)
J (Canada only)
The red brake system
warning lamp comes on
while the engine is
running. A warning tone
also sounds. There is not enough brake fluid in the brake fluid reservoir.
G WARNING
The braking effect may be impaired.
There is a risk of an accident.
X Pull over and stop the vehicle safely as soon as possible, paying
attention to road and traffic conditions. Do not continue driving
under any circumstances.
X Secure the vehicle against rolling away (Y page 164).
X Do not add brake fluid. Topping up will not remedy the
malfunction.
X Consult a qualified specialist workshop.
X Observe the additional display messages in the multifunction
display. !
The yellow ABS warning
lamp is lit while the
engine is running.
ABS (Anti-lock Brake System) is deactivated due to a malfunction.
BAS (Brake Assist), BAS PLUS, ESP
®
(Electronic Stability
Program), PRE-SAFE ®
, PRE-SAFE ®
Brake, the HOLD function, hill
start assist and ESP ®
trailer stabilization are therefore also
deactivated, for example.
ATTENTION ASSIST is deactivated.
G WARNING
The brake system continues to function normally, but without the
functions listed above. The wheels could therefore lock if you
brake hard, for example.
The steerability and braking characteristics may be severely
affected. The braking distance in an emergency braking situation
can increase.
If ESP ®
is not operational, ESP ®
is unable to stabilize the vehicle.
There is an increased risk of skidding and an accident.
X Observe the additional display messages in the multifunction
display.
X Drive on carefully.
X Visit a qualified specialist workshop.
If the ABS control unit is faulty, there is also a possibility that other
systems, such as the navigation system or the automatic
transmission, will not be available. Warning and indicator lamps in the instrument cluster
263On-board computer and displays Z