2014 MERCEDES-BENZ GL-Class PRE-SAFE

and
R if a vehicle speed of 15 mph (25 km/h) is
exceeded, the 7seat belt warning lamp
begins to flash. A warning tone also sounds
with increasing intensity for a maximum of
60 seconds or until the driver or front
passenger have fastened their seat belts.
If the driver/front passenger unfasten their
seat belt while the vehicle is in motion, the
7 seat belt warning lamp lights up and a
warning tone sounds again.
The warning tone ceases even if the driver or
front-passenger seat belt has still not been
fastened after 60 seconds. The 7seat belt
warning lamp stops flashing but remains
illuminated.
After the vehicle comes to a standstill, the
warning tone is reactivated. The 7seat
belt warning lamp flashes again if the vehicle
speed exceeds 15 mph (25 km/h).
The 7 seat belt warning lamp only goes
out if:
R both the driver and the front passenger
have fastened their seat belts.
or
R the vehicle is stationary and a door is open.
i For more information on the 7seat
belt warning lamp, see "Warning and
indicator lamps in the instrument cluster,
seat belts" ( Ypage 324).
Emergency Tensioning Devices, seat
belt force limiters G
WARNING
Pyrotechnic Emergency Tensioning Devices
that have been deployed are no longer
operational and are unable to perform their
intended protective function. This poses an
increased risk of injury or even fatal injury.
Therefore, have pyrotechnic Emergency
Tensioning Devices which have been
triggered immediately replaced at a qualified
specialist workshop. !
If the front-passenger seat is not
occupied, do not engage the seat belt
tongue in the buckle on the front-
passenger seat. Otherwise, the Emergency
Tensioning Device could be triggered in the
event of an accident.
i Vehicles with PRE-SAFE ®
: an electric
motor is used by PRE-SAFE ®
to trigger the
tightening of the seat belt in hazardous
situations. This procedure is reversible.
The seat belts on the following seats have
Emergency Tensioning Devices and seat belt
force limiters:
R driver's and front-passenger seat
R the outer seats in the second row
R the seats in the third row
The ETDs tighten the seat belts in an accident,
pulling them close against the body.
The ETDs do not correct incorrect seat
positions or incorrectly fastened seat belts.
The ETDs do not pull vehicle occupants back
towards the backrest.
If the seat belt is also equipped with a seat
belt force limiter and this is triggered, the
force exerted by the seat belt on the vehicle
occupant is reduced.
The seat belt force limiters for the front seats
are synchronized with the front air bags,
which absorb part of the deceleration force.
This results in the force exerted on the
occupant being distributed over a greater
area.
The ETDs can only be activated when:
R the ignition is switched on
R the restraint systems are operational; see
"SRS warning lamp" (Y page 43)
R the belt tongue is engaged in the buckle on
each of the lap-shoulder belts in the front
The Emergency Tensioning Devices on the
outside seats in the second row and on the
seats in the third row are triggered
independently of the lock status of the seat
belts. Occupant safety
59Safety Z

R
BAS PLUS ( BrakeAssist System Plus)
(Y page 68)
R COLLISION PREVENTION ASSIST (distance
warning function and adaptive Brake
Assist) (Y page 69)
R ESP ®
(Electronic StabilityProgram)
(Y page 72)
R EBD ( Electronic Brake force Distribution)
(Y page 74)
R ADAPTIVE BRAKE (Y page 75)
R PRE-SAFE ®
Brake (Y page 75)
R STEER CONTROL (Y page 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.
i The 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. (Y page 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 i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
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 (Y page 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 X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking
situation is over.
X To 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. Driving safety systems
67Safety Z

As a result, BAS PLUS may not 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.
Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else
covering the sensors
R there is interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
Function To avoid a collision, BAS PLUS calculates the
brake force necessary if:
R you approach an obstacle, and
R BAS PLUS has detected a risk of collision
When driving at a speed under 20 mph
(30 km/h): if you depress the brake pedal,
BAS PLUS is activated. The increase in brake
pressure will be carried out at the last
possible moment.
When driving at a speed above 20 mph
(30 km/h): if you depress the brake pedal
sharply, BAS PLUS automatically raises the
brake pressure to a value adapted to the
traffic situation.
BAS PLUS provides braking assistance in
hazardous situations with vehicles in front within a speed range between 4 mph
(7 km/h) and 155 mph (250 km/h).
At speeds of up to approximately 40 mph
(70 km/h), BAS PLUS can also react to
stationary objects. Examples of stationary
objects are stopped or parked vehicles.
i
If BAS PLUS demands particularly high
braking force, preventative passenger
protection measures (PRE-SAFE ®
) are
activated simultaneously.
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
BAS PLUS is deactivated and the brakes
function as usual again, if:
R you release the brake pedal.
R there is no longer a risk of collision.
R no obstacle is detected in front of your
vehicle.
If you have activated DSR (Y page 256), BAS
PLUS is likewise deactivated. COLLISION PREVENTION ASSIST
General notes COLLISION PREVENTION ASSIST consists of
Adaptive Brake Assist and the distance
warning function, which are described in the
following.
Distance warning function
Important safety notes
i
Observe the "Important safety notes"
section ( Ypage 67). G
WARNING
The distance warning function does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when cornering Driving safety systems
69Safety
Z

Adaptive Brake Assist
i
Observe the "Important safety notes"
section (Y page 67). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic
situations.
In such cases, Adaptive Brake Assist may:
R intervene unnecessarily
R not 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. G
WARNING
Adaptive Brake Assist does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R to stationary obstacles
R when 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.
X
Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will work normally again if:
R you release the brake pedal.
R there is no longer any danger of a collision.
R no 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:
R dirt on the sensors or anything else
covering the sensors
R there is snow or heavy rain
R there is interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike Driving safety systems
71Safety Z

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 (Y page 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
(Y page 216) and hill start assist
(Y page 171). PRE-SAFE
®
Brake
General information i
Observe the "Important safety notes"
section (Y page 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 G
WARNING
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. G
WARNING
PRE-SAFE ®
Brake cannot always clearly
identify objects and complex traffic
conditions.
In these cases, PRE-SAFE ®
Brake may:
R give an unnecessary warning and then
brake the vehicle
R not 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. G
WARNING
PRE-SAFE ®
Brake does not react:
R to people or animals
R to oncoming vehicles
R to crossing traffic
R when 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. Driving safety systems
75Safety Z

Recognition by the radar sensor system is
also impaired in the event of:
R dirt on the sensors or anything else
covering the sensors
R there is interference by other radar sources
R there are strong radar reflections, for
example in parking garages
R a narrow vehicle traveling in front, e.g. a
motorbike
R a vehicle traveling in front on a different line
relative to the center of your vehicle
Following damage to the front end of the
vehicle, have the configuration and operation
of the radar sensors checked at a qualified
specialist workshop. This also applies to
collisions at low speeds where there is no
visible damage to the front of the vehicle.
Function X
To activate/deactivate: activate or
deactivate PRE-SAFE ®
Brake in the on-
board computer (Y page 281).
If the PRE-SAFE ®
Brake is not activated, the
æ symbol appears in the multifunction
display.
Starting at a speed of around 4 mph
(7 km/h), this function warns you if you
rapidly approach a vehicle in front. An
intermittent warning tone will then sound and
the · distance warning lamp will light up
in the instrument cluster.
X Brake immediately to defuse the situation.
or
X Take evasive action provided it is safe to do
so.
PRE-SAFE ®
Brake can also brake the vehicle
automatically under the following conditions:
R the driver and front-passenger have their
seat belts fastened
and
R the vehicle speed is between
approximately 4 mph (7 km/h) and
124 mph (200 km/h) At speeds of up to approximately 40 mph
(70 km/h) PRE-SAFE ®
Brake can also detect
stationary objects. Examples of stationary
objects are stopped or parked vehicles.
i If there is an increased risk of collision,
preventive passenger protection measures
(PRE-SAFE ®
) are activated.
If the risk of collision with the vehicle in front
remains and you do not brake, take evasive
action or accelerate significantly, the vehicle
may perform automatic emergency braking,
up to the point of full brake application.
Automatic emergency braking is not
performed until immediately prior to an
imminent accident.
You can prevent the intervention of the PRE-
SAFE ®
Brake at any time by:
R depressing the accelerator pedal further.
R activating kickdown.
R releasing the brake pedal.
The braking action of PRE-SAFE ®
Brake is
ended automatically if:
R you maneuver to avoid the obstacle.
R there is no longer any danger of a collision.
R there is no longer an obstacle detected in
front of your vehicle.
If you have activated DSR (Y page 256), PRE-
SAFE ®
Brake is deactivated. STEER CONTROL
General information STEER CONTROL helps you by transmitting a
noticeable steering force to the steering
wheel in the direction required for vehicle
stabilization.
This steering assistance is provided in
particular if:
R both right wheels or both left wheels are on
a wet or slippery road surface when you
brake.
R the vehicle starts to skid. 76
Driving safety systemsSafety

If a course-correcting brake application
occurs, red warning lamp :flashes in the
exterior mirror and a dual warning tone
sounds. In addition, display ;underlining
the danger of a side collision appears in the
multifunction display.
In very rare cases, the system may make an
inappropriate brake application. A course-
correcting brake application may be
interrupted at any time if you steer slightly in
the opposite direction or accelerate.
The course-correcting brake application is
available in the speed range between
20 mph (30 km/h) and 120 mph (200 km/h).
Either no braking application, or a course-
correcting brake application adapted to the
driving situation occurs if:
R there are vehicles or obstacles, e.g. crash
barriers, located on both sides of your
vehicle.
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 the off-road program is activated (vehicles
without the ON&OFFROAD package).
R off-road program 1 or 2 is activated
(vehicles 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 is
detected.
Switching on Active Blind Spot Assist X
Make sure that the radar sensor system
(Y page 285) and Active Blind Spot Assist
(Y page 281) are activated in the on-board
computer.
X Turn the SmartKey to position 2in the
ignition 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
connection. 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 Active Blind Spot Assist Currently
Unavailable See Operator's Manual Unavailable See Operator's Manual
message appears in the multifunction
display. 250
Driving systemsDriving and parking

by means of intermittent vibration in the
steering wheel for up to 1.5 seconds.
In order that you are warned only when
necessary and in good time if you cross the
lane marking, the system recognizes certain
conditions 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
highway.
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 G
WARNING
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
application. G
WARNING
Active Lane Keeping Assist does not detect
traffic conditions or road users. In very rare
cases, the system may make an inappropriate
brake application, e.g. after intentionally
driving 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 a lane-correcting brake application occurs,
display :appears in the multifunction
display.
If you leave your lane, under certain
circumstances 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,
recognizable lane marking. Before this, a
warning must be given by means of
intermittent vibration 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
application 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. 252
Driving systemsDriving and parking