then have to steer and merge into traffic on
your own. PARKTRONIC is still available.
Canceling Active Parking Assist
You can cancel Active Parking Assist at any
time.
X Stop the movement of the multifunction
steering wheel or steer yourself.
Active Parking Assist will be canceled at
once. The
Park Assist Canceled mes-
sage appears in the multifunction display.
or
X Press the PARKTRONIC button on the cen-
ter console ( Y page 188).
PARKTRONIC is switched off and Active
Parking Assist is immediately canceled.
The
Park Assist Canceled message
appears in the multifunction display.
Active Parking Assist is canceled automati-
cally if: R transmission position P is selected
R parking using Active Parking Assist is no
longer possible
R you are driving faster than 6 mph (10 km/h)
R a wheel spins, ESP ®
intervenes or fails. The
÷ warning lamp lights up in the instru-
ment cluster.
A warning tone sounds. The parking symbol
goes out and the
Park Assist Canceled
message appears in the multifunction dis-
play.
If Active Parking Assist is canceled, you must
steer again yourself.
Towing a trailer
For vehicles with a trailer tow hitch, the min-
imum length for parking spaces is slightly
increased.
If you have attached a trailer to your vehicle,
you should not use Active Parking Assist.
Once the electrical connection is established between your vehicle and the trailer, Active
Parking Assist is no longer available.
PARKTRONIC is deactivated for the rear area.
Rear view camera
General notes
:Rear view camera
Rear view camera : is located in the handle
strip of the tailgate.
Rear view camera : is an optical parking and
maneuvering aid. It uses guide lines to show
the area behind your vehicle in the Audio/
COMAND display.
The area behind the vehicle is displayed as a
mirror image, as in the rear view mirror.
iThe text of messages shown in the
COMAND display depends on the language
setting. The following are examples of rear view camera messages in the COMAND
display.
Important safety notes
The rear view camera is only an aid. It is not a
replacement for your attention to your imme- diate surroundings. You are always responsi-
ble for safe maneuvering and parking. When
maneuvering or parking, make sure that there are no persons, animals or objects in the area
in which you are maneuvering.
Under the following circumstances, the rear
view camera will not function, or will function
in a limited manner:
R if the tailgate is open
R in heavy rain, snow or fog
R at night or in very dark places
R if the camera is exposed to very bright light
Driving systems193
Driving and parking
Z
Display with the PARKTRONIC display
Example: full screen mode with PARKTRONIC dis-
play :
Symbol for the full screen setting with rear
view camera image
If the vehicle is equipped with PARKTRONIC
and the function is active ( Y page 188), warn-
ing displays ; in the COMAND display are
also active or light up accordingly.
PARKTRONIC appears:
R in split screen view as red or yellow brack-
ets around the vehicle icon in the top view, or
R in the full screen view, on the right-hand
side at the bottom as red or yellow brackets
around the vehicle icon
iThe full screen display can also be selec-
ted as front view.
Exiting 360° camera display mode
As soon as your vehicle exceeds a speed of
19 mph (30 km/h) with the function activa-
ted, the function switches off. The COMAND
display switches back to the previously selec- ted view. You can also switch the display by
selecting the & symbol in the display and
pressing W the COMAND controller.
ATTENTION ASSIST
Important safety notes
ATTENTION ASSIST is only an aid to the
driver. It might not always recognize fatigue or increasing inattentiveness in time or fail to
recognize them at all. The system is not a
substitute for a well-rested and attentive
driver.
ATTENTION ASSIST helps you during long,
monotonous journeys, such as on highways.
It is active in the range between 50 mph
(80 km/h) and 112 mph (180 km/h).
If ATTENTION ASSIST detects typical indica-
tors of fatigue or increasing lapses in con-
centration on the part of the driver, it sug-
gests you take a break.
ATTENTION ASSIST assesses your level of
fatigue or lapses in concentration by taking
the following criteria into account: R your personal driving style, e.g. steering
characteristics
R journey details, e.g. time of day and length
of journey
The functionality of ATTENTION ASSIST is
restricted and warnings may be delayed or
not occur at all:
R if the road condition is poor, e.g. if the sur-
face is uneven or if there are potholes
R if there is a strong side wind
R if you have adopted a sporty driving style
with high cornering speeds or high rates of
acceleration
R if you are predominantly driving slower
than 50 mph (80 km/h) or faster than
112 mph (180 km/h)
R if you are currently using COMAND or mak-
ing a telephone call with it
R if the time has been set incorrectly
R in active driving situations, such as when
you change lanes or change your speed
Warning and display messages in the
multifunction display
XActivate ATTENTION ASSIST using the on-
board computer ( Y page 229).
If ATTENTION ASSIST is active, you will be
warned no sooner than 20 minutes after your journey has begun. You then hear an inter-
202Driving systems
Driving and parking
When towing a trailer, your vehicle's handling
characteristics will be different in comparison with when driving without a trailer.
Use the left-hand paddle shifter to shift into a
lower gear in good time on long and steep
downhill gradients.
iThis also applies if you have activated
cruise control.
This will use the braking effect of the engine,
so that less braking will be required to main-
tain the speed. This relieves the load on the
brake system and prevents the brakes from
overheating and wearing too quickly. If you
need additional braking, depress the brake
pedal repeatedly rather than continuously.
Driving tips
R Maintain a greater distance from the vehi-
cle in front than when driving without a
trailer.
R Avoid braking abruptly. If possible, brake
gently at first to allow the trailer to run on.
Then, increase the braking force rapidly.
R The values given for gradient-climbing
capabilities from a standstill refer to sea
level. When driving in mountainous areas,
note that the power output of the engine
and, consequently, the vehicle's gradient-
climbing capability, decreases with
increasing altitude.
If the trailer swings from side to side:
X Do not accelerate.
X Do not counter-steer.
X Brake if necessary.
Installing the ball coupling
GWARNING
If the ball coupling is not installed and secured
correctly the trailer may come loose. There is
a risk of an accident.
Install and secure the ball coupling as descri-
bed in the ball coupling installation instruc-
tions. Make sure that the ball coupling is
installed and secured correctly before every
journey.
! Mercedes-Benz recommends that you
only use ball couplings that have been tes- ted and approved by Mercedes-Benz. This
helps to avoid damage to the vehicle.
Cover cap
X Pull protective cap : in the direction of the
arrow, out of ball coupling recess ;.
X Store protective cap : in a safe place.
X Observe the manufacturer's installation
instructions.
GWARNING
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
214Towing a trailer
Driving and parking
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
GWARNING
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,
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.
iMercedes-Benz recommends a trailer
load where the trailer drawbar noseweight
accounts for 8% to 15% of the trailer's per-
missible gross weight.
216Towing a trailer
Driving and parking
Otherwise, the vehicle's electronic sys-
tem may be damaged.
R the transmission is locked in position P
after disconnecting the battery. The vehi-
cle is secured against rolling away. You
can then no longer move the vehicle.
The battery and the cover of the positive
terminal clamp must be installed securely
during operation.
Comply with safety precautions and take pro-
tective measures when handling batteries.
Risk of explosion.
Fire, open flames and smoking are
prohibited when handling the bat-
tery. Avoid creating sparks.
Battery acid is caustic. Avoid con-
tact with skin, eyes or clothing.
Wear suitable protective clothing,
especially gloves, apron and face-
guard.
Rinse any acid spills immediately
with clear water. Contact a physi-
cian if necessary.
Wear eye protection.
Keep children away.
Observe this Operator's Manual.
In order for the battery to achieve the maxi-
mum possible service life, it must always be
sufficiently charged.
Have the battery condition of charge checked
more frequently if you use the vehicle mainly for short trips or if you leave it standing idle
for a lengthy period. Consult a qualified spe- cialist workshop if you wish to leave your
vehicle parked for a long period of time.
Like other batteries, the vehicle battery may
discharge over time if you do not use the
vehicle. In this case, have the battery discon-
nected at a qualified specialist workshop. You can also charge the battery with a charger
recommended by Mercedes-Benz. Contact a
qualified specialist workshop for further infor-
mation.
iRemove the SmartKey if you park the
vehicle and do not require any electrical
consumers. The vehicle will then use very
little energy, thus conserving battery
power.
iIf the power supply has been interrupted,
e.g. if you reconnect the battery, you will
have to:
R set the clock; see the separate operating
instructions.
On vehicles with COMAND and a naviga- tion system, the clock is set automati-
cally.
R reset the panorama roof with power tilt/
sliding panel. ( Y page 97)
R reset the function for folding the exterior
mirrors in/out automatically by folding
the mirrors out once ( Y page 110) 12
.
Charging the battery
GWARNING
During charging and jump-starting, explosive
gases can escape from the battery. There is a
risk of an explosion.
Particularly avoid fire, open flames, creating
sparks and smoking. Ensure there is sufficient
ventilation while charging and jump-starting.
Do not lean over a battery.
GWARNING
Battery acid is caustic. There is a risk of injury.
12 This function is only available in vehicles for Canada.
Battery (vehicle)321
Roadside Assistance
Z
Jump-starting
For the jump-starting procedure, use only the jump-starting connection point, consisting of a
positive terminal and a ground point, in the engine compartmen t.
GWARNING
Battery acid is caustic. There is a risk of injury.
Avoid contact with skin, eyes or clothing. Do not inhale any battery gases. Do not lean over the
battery. Keep children away from batteries. Wash away battery ac id immediately with plenty of
clean water and seek medical attention.
GWARNING
During charging and jump-starting, explosive gases can e scape from the battery. There is a risk
of an explosion.
Particularly avoid fire, open flames, creating sparks and smoking. Ensure there is sufficient ven-
tilation while charging and jump-starting. Do not lean over a ba ttery.
GWARNING
During the charging process, a battery produces hydrogen gas. If a short circuit occurs or sparks
are created, the hydrogen gas can ignite. There is a risk of an explosi on.
R Make sure that the positive terminal of a connected battery does not come into contact with
vehicle parts.
R Never place metal objects or tools on a battery.
R It is important that you observe the described order of the battery terminals when connecting
and disconnecting a battery.
R When jump-starting, make sure that the battery poles with identical polarity are connected.
R It is particularly important to observe the described o rder when connecting and disconnecting
the jumper cables.
R Never connect or disconnect the battery terminals while the engin e is running.
GWARNING
Non-combusted fuel can collect in the exhaust system and ignite. The re is a risk of fire. Avoid
repeated and lengthy starting attempts.
! Vehicles with a gasoline engine: avoid repeated and lengthy starting attempts. Other-
wise, the catalytic converter could be damaged by non-combuste d fuel.
Do not start the vehicle using a rapid charging device. If your vehicle's battery is discharged,
the engine can be jump-started from another vehicle or from a secon d battery using jumper
cables. Observe the following points:
R The battery is not accessible in all vehicles. If the other vehicle's batt ery is not accessible,
jump-start the vehicle using a second battery or a jump-starting de vice.
R Vehicles with a gasoline engine: only jump-start the vehicle when the engine and exhaust
system are cold.
R Do not start the engine if the battery is frozen. Let the battery thaw first.
R Jump-starting may only be performed from batteries with a nomin al voltage of 12 V.
Jump-starting323
Roadside Assistance
Z
! Always use wheel bolts ; to mount the
collapsible spare wheel. Using other wheel
bolts to mount the collapsible spare wheel could damage the brake system.
Be sure to use the original-length wheel bolts
when re-mounting the original wheel after it
has been repaired.
! To prevent damage to the paintwork, hold
the wheel securely against the wheel hub
while screwing in the first wheel bolt.
X Clean the wheel and wheel hub contact
surfaces.
X Place the new wheel on the wheel hub and
push it on.
X Tighten the wheel bolts until they are fin-
ger-tight.
X Inflate the collapsible spare wheel
(Y page 367).
Only then lower the vehicle.
Lowering the vehicle
GWARNING
The wheels could work loose if the wheel nuts and bolts are not tightened to the specified
tightening torque. There is a risk of accident.
Have the tightening torque immediately
checked at a qualified specialist workshop
after a wheel is changed.
! Inflate the collapsible spare wheel using
the tire inflation compressor before lower-
ing the vehicle. The wheel rim could other-
wise be damaged.
X Place the ratchet wrench onto the hexagon
nut of the jack so that the letters AB are
visible.
X Turn the ratchet wrench until the vehicle is
once again standing firmly on the ground.
X Place the jack to one side.
X Tighten the wheel bolts evenly in a cross-
wise pattern in the sequence indicated ( :
to A ). The tightening torque must be
110 lb-ft (150 Nm) .
X Turn the jack back to its initial position and
store it together with the rest of the tire-
change tool kit in the cargo compartment.
X Transport the faulty wheel in the cargo
compartment.
X Check the tire pressure of the newly moun-
ted wheel and adjust it if necessary.
Observe the recommended tire pressure
( Y page 336).
For further information on stowing the col-
lapsible spare wheel, see ( Y page 367).
iWhen you are driving with the emergency
spare wheel mounted, the tire pressure
monitor cannot function reliably. Only
restart the tire pressure monitor when the
defective wheel has been replaced with a
new wheel. All wheels mounted must be
equipped with functioning sensors.
Mounting a wheel359
Wheels and tires
Z
Refrigerant instruction label
Example: refrigerant instruction label :
Warning symbol
;Refrigerant filling capacity
=Applicable standards
?PAG oil part number
AType of refrigerant
Warning symbol : advises you about:
R possible dangers
R having service work carried out at a quali-
fied specialist workshop
Filling capacities
All modelsCapacity
Refrigerant20.8 ± 0.4 oz
(590 ± 10 g)
PAG oil4.2 oz
(120 g)
Vehicle data
General notes
Please note that for the specified vehicle
data:
R the heights specified may vary as a result
of:
- tires
- load
- condition of the suspension
- optional equipment
R optional equipment reduces the maximum
payload.
Dimensions and weights
Model:
Opening
height
;
Max.
headroom
GLK 250 Blue-
TEC 4MATIC82.2 in
(2087 mm)77.0 in
(1955 mm)
All other mod-
els82.1 in
(2086 mm)76.9 in
(1954 mm)
All models
Vehicle length178.6 in (4536 mm)
Vehicle width
including exterior
mirrors79.4 in (2016 mm)
Wheelbase108.5 in (2755 mm)
380Vehicle data
Technical data