2015 MERCEDES-BENZ GLK-CLASS SUV brake light

Braking
Important safety notes
GWARNING
If you shift down on a slippery road surface in an attempt to increase the engine's braking
effect, the drive wheels could lose their grip.
There is an increased danger of skidding and
accidents.
Do not shift down for additional engine brak-
ing on a slippery road surface.
Downhill gradients
! On long and steep gradients, you must
reduce the load on the brakes by shifting
early to a lower gear. This allows you to take advantage of the engine braking effect and
helps avoid overheating and excessive
wear of the brakes.
When you take advantage of the engine
braking effect, a drive wheel may not turn
for some time, e.g. on a slippery road sur-
face. This could cause damage to the drive train. This type of damage is not covered bythe Mercedes-Benz warranty.
Heavy and light loads
GWARNING
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.
! Depressing the brake pedal constantly
results in excessive and premature wear to
the brake pads.
If the brakes have been subjected to a heavy load, do not stop the vehicle immediately.
Drive on for a short while. This allows the air-
flow to cool the brakes more quickly.
Wet roads
If you have driven for a long time in heavy rain without braking, there may be a delayed reac-
tion from the brakes when braking for the first time. This may also occur after the vehicle has
been washed.
You have to depress the brake pedal more
firmly. Maintain a greater distance from the
vehicle in front.
After driving on a wet road or having the vehi- cle washed, brake firmly while paying atten-
tion to the traffic conditions. This will warm up
the brake discs, thereby drying them more
quickly and protecting them against corro-
sion.
Limited braking performance on salt-
treated roads
If you drive on salted roads, a layer of salt
residue may form on the brake discs and
brake pads. This can result in a significantly
longer braking distance. R Brake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
R Carefully depress the brake pedal and the
beginning and end of a journey.
R Maintain a greater distance to the vehicle
ahead.
Servicing the brakes
! If the red brake warning lamp lights up in
the instrument cluster and you hear a warn-
ing tone while the engine is running, the
brake fluid level may be too low. Observe
additional warning messages in the multi-
function display.
The brake fluid level may be too low due to brake pad wear or leaking brake lines.
Have the brake system checked immedi-
ately. This work should be carried out at a
qualified specialist workshop.
All checks and maintenance work on the
brake system must be carried out at a quali-
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fied specialist workshop. Consult a qualified
specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
! Vehicles with 4MATIC: function or per-
formance tests may only be carried out on
a 2-axle dynamometer. If you are planning
to have the vehicle tested on such a dyna-
mometer, contact an authorized Mercedes- Benz Center to obtain further information
first. Otherwise, you could damage the
drive train or the brake system.
! As the ESP ®
system operates automati-
cally, the engine and the ignition must be
switched off (SmartKey in position 0 or 1 in
the ignition lock) when:
R testing the parking brake on a brake
dynamometer.
R you intend to have the vehicle towed with
the front or rear axle raised (not permit-
ted for vehicles with 4MATIC).
Braking maneuvers triggered automatically
by ESP ®
may seriously damage the brake
system.
If the brake system has only been subject to
moderate loads, you should test the function- ality of your brakes at regular intervals. To do so, press firmly on the brake pedal when driv-
ing at a high speed. This improves the grip of
the brake pads.
You can find a description of Brake Assist
(BAS) on ( Y page 69).
Mercedes-Benz recommends that you only
have brake pads/linings installed on your
vehicle which have been approved for
Mercedes-Benz vehicles or which correspond to an equivalent quality standard. Brake
pads/linings which have not been approved
for Mercedes-Benz vehicles or which are not
of an equivalent quality could affect your vehi-
cle's operating safety.
Mercedes-Benz recommends that you only
use brake fluid that has been specially
approved for your vehicle by Mercedes-Benz,
or which corresponds to an equivalent quality standard. Brake fluid which has not been
approved for Mercedes-Benz vehicles or
which is not of an equivalent quality could
affect your vehicle's operating safety.
Parking brake
GWARNING
If you must brake the vehicle with the parking
brake, the braking distance is considerably
longer and the wheels could lock. There is an
increased danger of skidding and accidents.
Only use the parking brake to brake the vehi-
cle when the service brake is faulty. Do not
apply the parking brake too firmly. If the
wheels lock, release the parking brake until
the wheels begin turning again.
If you brake the vehicle with the parking
brake, the brake lamps will not light up.
If you drive on wet roads or dirt-covered sur-
faces, road salt and/or dirt could get into the parking brake.
In order to prevent corrosion and a reduction
in the braking power of the parking brake,
observe the following:
R gently depress the parking brake from time
to time before beginning the journey.
R Drive for approximately 110 yds (100 m) at
a maximum speed of 12 mph (20 km/h).
Driving on wet roads
Hydroplaning
If water has accumulated to a certain depth
on the road surface, there is a danger of
hydroplaning occurring, even if: R you drive at low speeds.
R the tires have adequate tread depth.
For this reason, in the event of heavy rain or in
conditions in which hydroplaning may occur,
you must drive in the following manner:
R lower your speed.
R avoid ruts.
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Driving systems
Cruise control
Important safety notes
Cruise control maintains a constant road
speed for you. It brakes automatically in order
to avoid exceeding the set speed. You must
select a low gear in good time on long and
steep downhill gradients, especially if the
vehicle is laden or towing a trailer. By doing
so, you will make use of the braking effect of the engine. This relieves the load on the brake
system and prevents the brakes from over-
heating and wearing too quickly.
Use cruise control only if road and traffic con-
ditions make it appropriate to maintain a
steady speed for a prolonged period. You can store any road speed above 20 mph
(30 km/h).
If you fail to adapt your driving style, cruise
control can neither reduce the risk of an acci-
dent nor override the laws of physics. Cruise
control cannot take into account the road,
traffic and weather conditions. Cruise control is only an aid. You are responsible for the dis-
tance to the vehicle in front, for vehicle speed,for braking in good time and for staying in
your lane.
Do not use cruise control: R in road and traffic conditions which do not
allow you to maintain a constant speed e.g.
in heavy traffic or on winding roads
R on slippery road surfaces. Braking or accel-
erating could cause the drive wheels to lose traction and the vehicle could then skid
R when there is poor visibility, e.g. due to fog,
heavy rain or snow
If there is a change of drivers, advise the new driver of the speed stored.
iCruise control should not be activated
when driving off-road.
iThe speed indicated in the speedometer
may differ slightly from the speed stored.
Cruise control lever
:To activate or increase speed
;To activate or reduce speed
=To deactivate cruise control
?To activate at the current speed/last
stored speed
When you activate cruise control, the stored
speed is shown in the multifunction display
for five seconds. In the multifunction display,
the segments between the stored speed and
the maximum speed light up.
Storing and maintaining the current
speed
You can store the current speed if you are
driving faster than 20 mph (30 km/h). X Accelerate the vehicle to the desired
speed.
X Briefly press the cruise control lever up :
or down ;.
X Remove your foot from the accelerator
pedal.
Cruise control is activated. The vehicle
automatically maintains the stored speed.
iCruise control may be unable to maintain
the stored speed on uphill gradients. The
stored speed is resumed when the gradient evens out. Cruise control maintains the
stored speed on downhill gradients by
automatically applying the brakes.
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Crossing vehicles
DISTRONIC PLUS may mistakenly detect
vehicles that are crossing your lane. Activat-
ing DISTRONIC PLUS at traffic lights with
crossing traffic, for example, could cause
your vehicle to pull away unintentionally.
HOLD function
General notes
The HOLD function can assist the driver in the
following situations: R when pulling away, especially on steep
slopes
R when maneuvering on steep slopes
R when waiting in traffic
The vehicle is kept stationary without the
driver having to depress the brake pedal.
The braking effect is canceled and the HOLD
function deactivated when you depress the
accelerator pedal to pull away.
iDo not use the HOLD function when driv-
ing off-road, on steep uphill or downhill gra-
dients or on slippery or loose surfaces. The HOLD function cannot hold the vehicle on
such surfaces.
Important safety notes
GWARNING
When leaving the vehicle, it can still roll away despite being braked by the HOLD function if:
R there is a malfunction in the system or in
the voltage supply.
R the HOLD function has been deactivated by
pressing the accelerator pedal or the brake
pedal, e.g. by a vehicle occupant.
R the electrical system in the engine com-
partment, the battery or the fuses have
been tampered with.
R the battery is disconnected
There is a risk of an accident.
If you wish to exit the vehicle, always turn off the HOLD function and secure the vehicle
against rolling away.
! If DISTRONIC PLUS or the HOLD function
is activated, the vehicle brakes automati-
cally in certain situations. To prevent dam-
age to the vehicle, deactivate DISTRONIC
PLUS and the HOLD function in the follow-
ing or other similar situations:
R when towing the vehicle
R in the car wash
Deactivating the HOLD function
( Y page 185).
Activation conditions
You can activate the HOLD function if:
R the vehicle is stationary
R the engine is running or if it has been auto-
matically switched off by the ECO start/
stop function
R the driver's door is closed or your seat belt
is fastened
R the parking brake is released
R the hood is closed.
R the transmission is in position D, R or N
R DISTRONIC PLUS is deactivated
184Driving systems
Driving and parking

GWARNING
The Lane Keeping Assist warning does not
return the vehicle to the original lane. There isa risk of an accident.
You should always steer, brake or accelerate
yourself, in particular if warned by Lane Keep- ing Assist.
The Lane Keeping Assist does not keep the
vehicle in the lane.
The system may be impaired or may not func-
tion if:
R there is poor visibility, e.g. due to insuffi-
cient illumination of the road, or due to
snow, rain, fog or spray
R there is glare, e.g. from oncoming traffic,
the sun or reflections (e.g. when the road
surface is wet)
R the windshield is dirty, fogged up, damaged
or covered, for instance by a sticker, in the
vicinity of the camera
R there are no, several or unclear lane mark-
ings for a lane, e.g. in areas with road con- struction work
R the lane markings are worn away, dark or
covered up, e.g. by dirt or snow
R the distance to the vehicle in front is too
small and the lane markings thus cannot be
detected
R the lane markings change quickly, e.g.
lanes branch off, cross one another or
merge
R the road is narrow and winding
R there are strong shadows cast on the lane
Switching on Lane Keeping Assist X Switch on Active Lane Keeping Assist using
the on-board computer; to do so, select
Standard or Adaptive( Y page 230).
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 229) are shown in green. Lane
Keeping Assist is ready for use. Standard
If
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 ®
.
Adaptive
When
Adaptive is selected, no warning vibra-
tion 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, e.g.
ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard.
R you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
In order that you are warned only when nec-
essary and in good time if you cross the lane marking, the system recognizes certain con-
ditions and warns you accordingly.
The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a high-
way.
R the system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.
Towing a trailer
When you attach a trailer, make sure you have correctly established the electrical connec-
tion. This can be accomplished by checking
the trailer lighting.
206Driving systems
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The yellow indicator lamp goes out if reversegear is engaged. In this event, Active Blind
Spot Assist is no longer active.
The brightness of the indicator/warning
lamps is adjusted automatically according to
the ambient light.
Visual and acoustic collision warning
When you switch on the turn signals to
change lanes and a vehicle is detected in the
side monitoring range, you receive a visual
and acoustic collision warning. You then hear a double warning tone and red warning
lamp : flashes. If the turn signal remains on,
detected vehicles are indicated by the flash-
ing of red warning lamp :. There are no fur-
ther warning tones.
Course-correcting brake application
GWARNING
A course-correcting brake application cannot always prevent a collision. There is a risk of an
accident.
Always steer, brake or accelerate yourself,
especially if Active Blind Spot Assist warns
you or makes a course-correcting brake appli-
cation. Always maintain a safe distance at the sides.
In very rare cases, the system may make an
inappropriate brake application. An inappro-
priate brake application may be interrupted at any time if you steer slightly in the opposite
direction or accelerate.
If Active Blind Spot Assist detects a risk of a
lateral collision in the monitoring range, a
course-correcting brake application is carried
out. This is meant to assist you in avoiding a
collision.
The course-correcting brake application is
available in the speed range between 20 mph (30 km/h) and 120 mph (200 km/h).
If a course-correcting brake application
occurs, red warning lamp : flashes in the
exterior mirror and the following is shown in
the multifunction display, for example:
Either a very slight course-correcting brake
application, or none at all, may occur if: R there are vehicles or obstacles, e.g. crash
barriers, located on both sides of your vehi-
cle.
R a vehicle approaches you too closely at the
side.
R you have adopted a sporty driving style with
high cornering speeds.
R you clearly brake or accelerate.
R a driving safety system intervenes, e.g.
ESP ®
or PRE-SAFE ®
Brake.
R ESP ®
is switched off.
R a loss of tire pressure or a defective tire is
detected.
Switching on Active Blind Spot Assist X Make sure that Active Blind Spot Assist
(Y page 229) is activated in the on-board
computer.
X Turn the SmartKey to position 2 in the igni-
tion lock.
Warning lamps : in the exterior mirrors
light up red for approximately 1.5 seconds
and then turn yellow.
Towing a trailer
When you attach a trailer, make sure you have
correctly established the electrical connec-
tion. This can be accomplished by checking
the trailer lighting. Active Blind Spot Assist is then deactivated. The indicator lamp lights up
yellow in the exterior mirrors and the
Active
Blind Spot Assist Currently UnavailZ
able See Operator's Manual message
appears in the multifunction display.
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means of intermittent vibration in the steer-
ing wheel for up to 1.5 seconds.
In order that you are warned only when nec-
essary and in good time if you cross the lanemarking, the system recognizes certain con-
ditions and warns you accordingly.
The warning vibration occurs earlier if:
R you approach the outer lane marking on a
bend.
R the road has very wide lanes, e.g. a high-
way.
R the system recognizes solid lane markings.
The warning vibration occurs later if:
R the road has narrow lanes.
R you cut the corner on a bend.
Lane-correcting brake application
GWARNING
A lane-correcting brake application cannot
always bring the vehicle back into the original lane. There is a risk of an accident.
Always steer, brake or accelerate yourself,
especially if Active Lane Keeping Assist warns
you or makes a lane-correcting brake appli-
cation.
GWARNING
Active Lane Keeping Assist does not detect
traffic conditions or road users. In very rare
cases, the system may make an inappropriatebrake application, e.g. after intentionally driv-
ing over a solid lane marking. There is a risk of an accident.
An inappropriate brake application may be
interrupted at any time if you steer slightly in
the opposite direction. Always make sure that
there is sufficient distance on the side for
other traffic or obstacles.
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.
If a lane-correcting brake application occurs,
the following, for example, appears in the
multifunction display:
iA 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 signals.
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 on vehicles with a trailer tow hitch, the
electrical connection to the trailer has been
correctly established.
R ESP ®
is switched off.
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Rthe transmission is not in position D.
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 you have switched on the turn signals
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 or Adaptive ( Y page 230).
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 229) are shown in green. Lane
Keeping Assist is ready for use.
If
Standard is selected, no warning vibra-
tion occurs if:
R you have switched 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 is selected, no warning
vibration occurs if:
R you have switched on the turn signals. In
this event, the warnings are suppressed
for a certain period of time.
R a driving safety system intervenes, e.g.
ABS, BAS or ESP ®
.
R you accelerate hard, e.g. kickdown.
R you brake hard. R
you steer actively, e.g. swerve to avoid an
obstacle or change lanes quickly.
R you cut the corner on a sharp bend.
Towing a trailer
When you attach a trailer, make sure you have correctly established the electrical connec-
tion. This can be accomplished by checking
the trailer lighting.
Towing a trailer
Notes on towing a trailer
Important safety notes
GWARNING
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.
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
212Towing a trailer
Driving and parking