2014 MERCEDES-BENZ GL air condition

ProblemPossible causes/consequences andPPSolutions
The PASSENGER AIR
BAG OFF indicator
lamp does not light up
and/or stays on.
The front-passenger
seat is:
Runoccupied
Roccupied with the
weight of a child up
to twelve months old
in a child restraint
system
The OCS is malfunctioning.
XMake sure there is nothing between the seat cushion and the
child seat.
XMake sure that the backrest and base of the child restraint
system are resting securely on the front-passenger seat. If
necessary, adjust the position of the front-passenger seat.
XWhen installing the child restraint system, make sure that the
seat belt is tight. Do not pull the seat belt tight with the front-
passenger seat adjustment. This could result in the seat belt
being pulled too tightly.
XCheck the installation of the child restraint system.
XMake sure that no objects are applying additional weight onto
the seat.
XIf the PASSENGER AIR BAG OFF indicator lamp remains off, have
the OCS system checked as soon as possible at a qualified
specialist workshop. Do not transport a child on the front-
passenger seat until the OCS has been repaired.
XObserve the additional display messages in the multifunction
display (Ypage 301).
PRE-SAFE®(anticipatory occupant
protection system)
Introduction
PRE-SAFE®takes preemptive measures to
protect occupants in certain hazardous
situations.
Important safety notes
!Make sure that there are no objects in the
footwell or behind the seats when resetting
the seats. There is a risk that the seats
and/or the objects could be damaged.
Despite your vehicle being equipped with the
PRE-SAFE®system, the possibility of
personal injuries occurring as a result of an
accident cannot be eliminated.
Always adapt your driving style to suit the
prevailing road and weather conditions and
maintain a safe distance from the vehicle in
front. Drive carefully.
Function
PRE-SAFE®intervenes:
Rin emergency braking situations, e.g. when
BAS is activated.
Rin critical driving situations, e.g. when
physical limits are exceeded and the
vehicle understeers or oversteers severely.
Ron vehicles with DISTRONIC PLUS:if
BAS PLUS brakes hard or the radar sensor
system detects an imminent danger of
collision in certain situations.
PRE-SAFE®takes the following measures
depending on the hazardous situation
detected:
Rthe front seat belts are pre-tensioned.
Rif the vehicle skids, the sliding sunroof and
the side windows are closed so that only a
small gap remains. On vehicles with a
panorama roof with power tilt/sliding
panel, they are closed completely.
54Occupant safety
Safety

RBAS PLUS (BrakeAssistSystem Plus)
(Ypage 68)
RCOLLISION PREVENTION ASSIST (distance
warning function and adaptive Brake
Assist) (Ypage 69)
RESP®(ElectronicStabilityProgram)
(Ypage 72)
REBD (ElectronicBrake forceDistribution)
(Ypage 74)
RADAPTIVE BRAKE (Ypage 75)
RPRE-SAFE®Brake (Ypage 75)
RSTEER CONTROL (Ypage 76)
Important safety notes
If you fail to adapt your driving style or
become distracted, the driving safety
systems can neither reduce the risk of
accident nor override the laws of physics.
Driving safety systems are merely aids
designed to assist driving. You are
responsible for the distance to the vehicle in
front, for vehicle speed and for braking in
good time. Always adapt your driving style to
suit the prevailing road and weather
conditions and maintain a safe distance from
the vehicle in front. Drive carefully.
iThe driving safety systems described only
work as effectively as possible when there
is adequate contact between the tires and
the road surface. Please pay special
attention to the notes on tires,
recommended minimum tire tread depths,
etc. (Ypage 404).
In wintry driving conditions, always use
winter tires (M+S tires) and if necessary,
snow chains. Only in this way will the
driving safety systems described in this
section work as effectively as possible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a way
that the wheels do not lock when you brake.
This allows you to continue steering the
vehicle when braking.
The%ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
Important safety notes
iObserve the "Important safety notes"
section (Ypage 67).
GWARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking
characteristics may be severely impaired.
Additionally, further driving safety systems
are deactivated. There is an increased danger
of skidding and accidents.
Drive on carefully. Have ABS checked
immediately at a qualified specialist
workshop.
When ABS is malfunctioning, other systems,
including driving safety systems, will also
become inoperative. Observe the information
on the ABS warning lamp (Ypage 326) and
display messages which may be shown in the
instrument cluster (Ypage 291).
ABS works from a speed of about 5 mph
(8 km/h), regardless of road-surface
conditions. ABS works on slippery surfaces,
even when you only brake gently.
Braking
XIf ABS intervenes:continue to depress the
brake pedal vigorously until the braking
situation is over.
XTo make a full brake application:
depress the brake pedal with full force.
If ABS intervenes when braking, you will feel
a pulsing in the brake pedal.
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Adaptive Brake Assist
iObserve the "Important safety notes"
section (Ypage 67).
GWARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic
situations.
In such cases, Adaptive Brake Assist may:
Rintervene unnecessarily
Rnot intervene
There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake. Terminate the
intervention in a non-critical driving situation.
GWARNING
Adaptive Brake Assist does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rto stationary obstacles
Rwhen cornering
As a result, Adaptive Brake Assist may not
intervene in all critical conditions. There is a
risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
Due to the nature of the system, particularly
complicated but non-critical driving
conditions may also cause Brake Assist to
intervene.
Adaptive Brake Assist aids you in braking
during hazardous situations at speeds above
4 mph (7 km/h) and uses the radar sensor
system to evaluate the traffic situation.
With the help of Adaptive Brake Assist, the
distance warning signal can detect obstacles
that are in the path of your vehicle for an
extended period of time.
Should you approach an obstacle and
Adaptive Brake Assist has detected a risk of
collision, Adaptive Brake Assist calculates the
braking force necessary to avoid a rear-end
collision. Should you apply the brakes
vigorously, Adaptive Brake Assist will
automatically increase the braking force to a
level suitable for the traffic conditions.
XKeep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
Ryou release the brake pedal.
Rthere is no longer any danger of a collision.
Rno obstacle is detected in front of your
vehicle.
Adaptive Brake Assist is then deactivated.
Vehicles with PRE-SAFE®:if adaptive Brake
Assist requires particularly high brake
pressure, preventive passenger protection
measures (PRE-SAFE®) are deployed
simultaneously.
Up to vehicle speeds of around 155 mph
(250 km/h), adaptive Brake Assist is capable
of reacting to moving objects that have
already been recognized as such at least once
over the period of observation. Adaptive
Brake Assist does not react to stationary
obstacles.
If Adaptive Brake Assist is not available due
to a malfunction in the radar sensor system,
the brake system remains available with full
brake boosting effect and BAS.
In particular, the detection of obstacles can
be impaired if there is:
Rdirt on the sensors or anything else
covering the sensors
Rthere is snow or heavy rain
Rthere is interference by other radar sources
Rthere are strong radar reflections, for
example in parking garages
Ra narrow vehicle traveling in front, e.g. a
motorbike
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You should therefore adapt your driving style
to the different handling characteristics. Have
the brake system checked at a qualified
specialist workshop.
Observe information regarding indicator and
warning lamps (Ypage 327) as well as
display messages (Ypage 293).
ADAPTIVE BRAKE
ADAPTIVE BRAKE enhances braking safety
and offers increased braking comfort. In
addition to the braking function, ADAPTIVE
BRAKE also has the HOLD function
(Ypage 216) and hill start assist
(Ypage 171).
PRE-SAFE®Brake
General information
iObserve the "Important safety notes"
section (Ypage 67).
PRE-SAFE®Brake is only available in vehicles
with DISTRONIC PLUS.
For PRE-SAFE®Brake to assist you when
driving, the radar sensor system must be
operational.
With the help of the radar sensor system,
PRE-SAFE®Brake can detect obstacles that
are in front of your vehicle for an extended
period of time.
PRE-SAFE®Brake can help you to minimize
the risk of a collision with a vehicle ahead, and
reduce the effects of such a collision. If PRE-
SAFE®Brake has detected a risk of collision,
you will be warned visually and acoustically
as well as by automatic braking. PRE-SAFE®
Brake cannot prevent a collision without your
intervention.
Important safety notes
GWARNING
PRE-SAFE®Brake will initially brake your
vehicle by a partial application of the brakes
if a danger of collision is detected. There may
be a collision unless you also brake.
Automatic emergency braking cannot prevent
a collision. There is a risk of an accident.
Always apply the brakes yourself and try to
take evasive action.
GWARNING
PRE-SAFE®Brake cannot always clearly
identify objects and complex traffic
conditions.
In these cases, PRE-SAFE®Brake may:
Rgive an unnecessary warning and then
brake the vehicle
Rnot give a warning or intervene
There is a risk of an accident.
Always pay particular attention to the traffic
situation and be ready to brake, especially if
PRE-SAFE®Brake warns you. Terminate the
intervention in a non-critical driving situation.
In order to maintain the appropriate distance
to the vehicle in front and thus prevent a
collision, you must apply the brakes yourself.
GWARNING
PRE-SAFE®Brake does not react:
Rto people or animals
Rto oncoming vehicles
Rto crossing traffic
Rwhen cornering
As a result, PRE-SAFE®Brake may neither
give warnings nor intervene in all critical
situations. There is a risk of an accident.
Always pay careful attention to the traffic
situation and be ready to brake.
In the event of snowfall or heavy rain, the
recognition can be impaired.
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Useful information
iThis Operator's Manual describes all
models and all standard and optional
equipment 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.
iRead the information on qualified
specialist workshops: (Ypage 28).
Overview of climate control systems
Important safety notes
Observe the settings recommended on the
following pages. The windows could
otherwise fog up.
To prevent the windows from fogging up:
Rswitch off climate control only briefly
Rswitch on air-recirculation mode only
briefly
Rswitch on the cooling with air
dehumidification function
Rswitch on the defrost windshield function
briefly, if required
Climate control regulates the temperature
and the humidity in the vehicle interior and
filters undesirable substances out of the air.
Climate control can only be operated when
the engine is running. Optimum operation is
only achieved with the side windows and roof
closed.
The residual heat function can only be
activated or deactivated with the ignition
switched off (Ypage 161).
iVentilate the vehicle for a brief period
during warm weather, e.g. using the
convenience opening feature (Ypage 95).
This will speed up the cooling process and
the desired interior temperature will be
reached more quickly.
iThe integrated filter filters out most
particles of dust and soot and completely
filters out pollen. It also reduces gaseous
pollutants and odors. A clogged filter
reduces the amount of air supplied to the
vehicle interior. For this reason, you should
always observe the interval for replacing
the filter, which is specified in the
Maintenance Booklet. As it depends on
environmental conditions, e.g. heavy air
pollution, the interval may be shorter than
stated in the Maintenance Booklet.
iIt is possible that the residual heat
function may be activated automatically an
hour after the SmartKey has been removed
in order to dry the automatic climate
control. The vehicle is then ventilated for
30 minutes.
146Overview of climate control systems
Climate control

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
airflow 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
reaction from the brakes when braking for the
first time. This may also occur after the
vehicle has been washed or driven through
deep water.
You then 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
vehicle washed, brake firmly while paying
attention to the traffic conditions. This will
warm up the brake discs, thereby drying them
more quickly and protecting them against
corrosion.
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.
RBrake occasionally to remove any possible
salt residue. Make sure that you do not
endanger other road users when doing so.
RCarefully depress the brake pedal and the
beginning and end of a journey.
RMaintain 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
warning tone while the engine is running,
the brake fluid level may be too low.
Observe additional warning messages in
the multifunction display.
The brake fluid level may be too low due to
brake pad wear or leaking brake lines.
Have the brake system checked
immediately. This work should be carried
out at a qualified specialist workshop.
!A function or performance test should
only be carried out on a 2-axle
dynamometer. If you are planning to have
the vehicle tested on such a dynamometer,
contact an authorized Mercedes-Benz
Center to obtain further information first.
Otherwise, you could damage the drive
train or the brake system.
!Because ESP®is an automatic system,
the engine and ignition must be switched
off (SmartKey in position0or1or Start/
Stop button in position0or1) when the
electric parking brake is being tested on a
brake dynamometer (maximum
10 seconds).
Braking triggered automatically by ESP®
may seriously damage the brake system.
All checks and maintenance work on the
brake system must be carried out at a
qualified specialist workshop. Consult a
qualified specialist workshop to arrange this.
Have brake pads installed and brake fluid
replaced at a qualified specialist workshop.
If the brake system has only been subject to
moderate loads, you should test the
functionality of your brakes at regular
intervals. To do so, press firmly on the brake
pedal when driving at a high speed. This
improves the grip of the brake pads.
You can find a description of Brake Assist
(BAS) on (Ypage 68) or of BAS PLUS on
(Ypage 68).
194Driving tips
Driving and parking

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
vehicle'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.
High-performance brake system for
AMG vehicles
The high-performance brake system is
designed for heavy loads. This may lead to
noise when braking. This will depend on:
RSpeed
RBraking force
REnvironmental conditions, such as
temperature and humidity
The wear of individual components of the
brake system, such as the brake pads/linings
or brake discs, depends on the individual
driving style and operating conditions.
For this reason, it is impossible to state a
mileage that will be valid under all
circumstances. An aggressive driving style
will lead to high wear. You can obtain further
information about this from your authorized
Mercedes-Benz Center.
New and replaced brake pads and discs only
reach their optimum braking effect after
several hundred kilometers of driving.
Compensate for this by applying greater force
to the brake pedal. Keep this in mind, and
adapt your driving and braking accordingly
during this break-in period.
Excessive heavy braking results in
correspondingly high brake wear. Observe
the&brake wear warning lamp in the
instrument cluster and note any brake status
messages in the multifunction display.
Especially for high performance driving, it is
important to maintain and have the brake
system checked regularly.
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:
Ryou drive at low speeds.
Rthe 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:
Rlower your speed.
Ravoid ruts.
Rbrake carefully.
Driving on flooded roads
!Do not drive through flooded areas.
Check the depth of any water before driving
through it. Drive slowly through standing
water. Otherwise, water may enter the
vehicle interior or the engine compartment.
This can damage the electronic
components in the engine or the automatic
transmission. Water can also be drawn in
by the engine's air suction nozzles and this
can cause engine damage.
iVehicles with the AIRMATIC package:
set the raised level before driving through
standing water.
Off-road fording
!Under no circumstances should you
accelerate before entering the water. The
Driving tips195
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conditions when temperatures are around
the freezing point.
For more information on driving with snow
chains, see (Ypage 407).
For more information on driving with summer
tires, see (Ypage 406).
Observe the notes in the "Winter operation"
section (Ypage 406).
Off-road driving
Important safety notes
GWARNING
If you drive on a steep incline at an angle or
turn when driving on an incline, the vehicle
could slip sideways, tip and rollover. There is
a risk of an accident.
Always drive on a steep incline in the line of
fall (straight up or down) and do not turn the
vehicle.
GWARNING
If the vehicle level is high, the vehicle center
of gravity is raised. This could cause the
vehicle to tip over more easily on uphill or
downhill gradients. There is a risk of an
accident.
Select the lowest possible vehicle level.
When driving off-road, sand, mud and water,
possibly mixed with oil, for example, could get
into the brakes. This could result in a reduced
braking effect or in total brake failure and also
in increased wear and tear. The braking
characteristics change depending on the
material ingressing the brakes. Clean the
brakes after driving off-road. If you detect a
reduced braking effect or grinding noises,
have the brake system checked in a qualified
specialist workshop as soon as possible.
Adapt your driving style to the different
braking characteristics.
Driving off-road increases the likelihood of
damage to the vehicle, which, in turn, can lead
to failure of the mechanical assembly or
systems. Adapt your driving style to suit the
terrain conditions. Drive carefully. Have
damage to the vehicle rectified immediately
at a qualified specialist workshop.
Do not switch to transmission positionN
when driving off-road. You could lose control
of the vehicle if you attempt to brake using
the service brake. If the gradient is too steep,
drive backwards in reverse gear.
General notes
Read this section carefully before driving your
vehicle off-road. Practice by driving over more
gentle off-road terrain first.
Familiarize yourself with the characteristics
of your vehicle and the gear shift operation
before driving through difficult terrain.
The following driving systems are specially
adapted to off-road driving:
ROff-road program 1 and 2 (vehicles with the
ON&OFFROAD package) (Ypage 258)
RLOW RANGE off-road gear (vehicles with
the ON&OFFROAD package)
(Ypage 259)
RDifferential lock (vehicles with the
ON&OFFROAD package) (Ypage 259)
ROff-road ABS (Ypage 68)
RAIRMATIC package (vehicle level)
(Ypage 217)
RDSR (Downhill Speed Regulation)
(Ypage 256)
Observe the following notes:
RStop the vehicle before starting to drive
along an off-road route.
RFor vehicles with the AIRMATIC
package:select a vehicle level that is
suitable for the off-road terrain. To avoid
damaging the vehicle, make sure there is
always sufficient ground clearance.
RCheck that items of luggage and loads are
stowed safely and are well secured
(Ypage 345).
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