Driving safety systems
Overview of driving safety systems
In this section, you will find information about
the following driving safety systems:
R ABS (Anti-lock BrakingSystem)
(Y page 66)
R BAS (Brake AssistSystem) (Y page 67)
R Active Brake Assist (Y page 67)
R ESP ®
(E lectronic StabilityProgram)
(Y page 70)
R EBD (Electronic Brake forceDistribution)
(Y page 72)
R ADAPTIVE BRAKE (Y page 72)
R Active Brake Assist with cross-traffic function
(Y page 72)
R Active Steering Assist STEER CONTROL
(Y page 75) Important safety notes
If you fail to adapt your driving style or if you are
inattentive, the driving safety systems can nei-
ther reduce the risk of an accident nor override the laws of physics. Driving safety systems are
merely aids designed to assist driving. You are
responsible for maintaining the distance to the
vehicle in front, for vehicle speed, for braking in
good time, and for staying in lane. 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.
The driving safety systems described only work
as effectively as possible when there is ade-
quate contact between the tires and the road
surface. Pay particular attention to the informa- tion regarding tires, recommended minimum
tire tread depths etc. in the "Wheels and tires"
section (Y page 351).
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 0025 ABS warning lamp in the instrument
cluster lights up when the ignition is switched
on. It goes out when the engine is running.
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.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 66). G
WARNING
If ABS is faulty, the wheels could lock when
braking. The steerability and braking charac-
teristics may be severely impaired. Addition-
ally, further driving safety systems are deac-
tivated. There is an increased danger of skid- ding and accidents.
Drive on carefully. Have ABS checked imme-
diately 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 (Y page 277) and dis-
play messages which may be shown in the
instrument cluster (Y page 245).
Brakes X
If ABS intervenes: continue to depress the
brake pedal vigorously until the braking sit-
uation 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.
The pulsating brake pedal can be an indication
of hazardous road conditions, and functions as a
reminder to take extra care while driving. 66
Driving safety systemsSafety
Off-road ABS
An ABS system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated on:
R Vehicles without the Offroad Engineering
package (Y page 215)
R Vehicles with the Off-Road Engineering pack-
age (Y page 216)
At speeds below 20 mph (30 km/h), the front
wheels lock cyclically during braking. The dig-
ging-in effect achieved in the process reduces
the stopping distance on off-road terrain. This
limits steering capability. BAS (Brake Assist System)
General information BAS operates in emergency braking situations.
If you depress the brake pedal quickly, BAS
automatically boosts the braking force, thus
shortening the stopping distance.
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 66). G
WARNING
If BAS is malfunctioning, the braking distance
in an emergency braking situation is
increased. There is a risk of an accident.
In an emergency braking situation, depress
the brake pedal with full force. ABS prevents
the wheels from locking.
Braking X
Keep the brake pedal firmly depressed until
the emergency braking situation is over.
ABS prevents the wheels from locking.
The brakes will function as usual once you
release the brake pedal. BAS is deactivated. Active Brake Assist
General information i
Observe the "Important safety notes" sec-
tion (Y page 66).
Active Brake Assist consists of a distance warn-
ing function with an autonomous braking func-
tion and situation-dependent braking assis-
tance.
Active Brake Assist can help you to minimize the risk of a collision with the vehicle traveling in
front or reduce the effects of such a collision.
If Active Brake Assist detects that there is a risk
of collision, you will be warned visually and
acoustically. If you do not react to the visual and audible collision warning, autonomous braking
can be initiated in critical situations. If you apply
the brake yourself in a critical situation, Active
Brake Assist supports you with situation-
dependent braking assistance.
Active Brake Assist is only available in certain
countries.
Important safety notes In particular, the detection of obstacles can be
impaired if:
R
there is 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 exam-
ple in parking garages
R a narrow vehicle is traveling in front, e.g. a
motorbike
R a vehicle is traveling in front on a different line
R you are driving a new vehicle or servicing on
the Active Brake Assist system has just been
carried out
Observe the notes in the section on breaking-
in (Y page 134).
Following damage to the front end of the vehicle, have the configuration and operation of the
radar sensor checked at a qualified specialist
workshop. This also applies to collisions at slow
speeds where there is no visible damage to the front of the vehicle. Driving safety systems
67Safety Z
Vehicles with Active Distance Assist
DISTRONIC: the autonomous braking function
is available in the following speed ranges:
R 4 - 124 mph (7 - 200 km/h) for moving
objects
R 4 - 31 mph (7 - 50 km/h) for stationary
objects
Due to the nature of the system, particularly
complicated but non-critical driving conditions
may also cause the Autonomous Braking Func-
tion to intervene.
If the autonomous braking function requires a
particularly high braking force, preventative
passenger protection measures (PRE-SAFE ®
)
are activated simultaneously (Y page 58).
Situation-dependent braking assis-
tance General information
i Observe the "Important safety notes" sec-
tion (Y page 66).
With the help of the radar sensor system, Active Brake Assist can detect obstacles that are in the
path of your vehicle for an extended period of
time.
If Active Brake Assist detects a risk of collision
with the vehicle in front, it calculates the brake
pressure necessary to avoid a collision. If you
apply the brakes forcefully, situation-dependent
braking assistance adapts to the situation and
automatically increases the brake pressure to a degree appropriate to the traffic situation.
Situation-dependent braking assistance pro-
vides braking assistance in hazardous situations at speeds above 4 mph (7 km/h). It uses radar
sensor technology to assess the traffic situa-
tion.
Situation-dependent braking assistance is capa-
ble of reacting to moving objects that have
already been detected as such at least once
over the period of observation, up to vehicle
speeds of around 155 mph (250 km/h).
Situation-dependent braking assistance reacts
to stationary obstacles up to a speed of approx-
imately 44 mph (70 km/h).
If situation-dependent braking assistance
demands particularly high brake pressure, pre-
ventative passenger protection measures (PRE-
SAFE ®
) are triggered simultaneously
(Y page 58). 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 vehi-
cle.
Situation-dependent braking assistance is then
deactivated.
Important safety notes i Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 66). G
WARNING
Adaptive Brake Assist cannot always clearly
identify objects and complex traffic situa-
tions.
In such cases, Adaptive Brake Assist might:
R intervene unnecessarily
R not intervene
There is a risk of an accident.
Always pay careful attention to the traffic sit- uation 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 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 sit- uation and be ready to brake.
Due to the nature of the system, complex but
non-critical driving conditions may also cause
Active Brake Assist to intervene.
Even if Active Brake Assist is not available due to a malfunction in the radar sensor system, the
brake system is still available with full brake
boosting effect and BAS. Driving safety systems
69Safety Z
Offroad ESP
®
(vehicles with Off-Road
Engineering package) An ESP
®
system specifically suited to off-road
terrain is activated automatically once the off-
road program is activated on:
R Vehicles without the Offroad Engineering
package (Y page 215)
R Vehicles with the Off-Road Engineering pack-
age (Y page 216)
Offroad ESP ®
intervenes with a delay if there is
oversteering or understeering, thus improving
traction.
Crosswind Assist General information
Strong crosswind gusts can impair the ability of your vehicle to drive straight ahead. The cross-
wind driving assistance function integrated in
ESP ®
noticeably reduces these impairments.
ESP ®
intervenes automatically according to the
direction and intensity of the crosswinds affect-
ing your vehicle.
ESP ®
intervenes with stabilizing braking to
assist you in keeping the vehicle in the lane.
Crosswind Assist is active at vehicle speeds
above 50 mph (80 km/h) when driving straight
ahead or cornering gently.
Important safety notes
Crosswind Assist does not work if ESP ®
is
switched off or deactivated because of a mal-
function. EBD (electronic brake force distribu-
tion)
General information EBD monitors and controls the brake pressure
on the rear wheels to improve driving stability
while braking.
Important safety notes i
Observe the "Important safety notes" sec-
tion for driving safety systems (Y page 66). G
WARNING
If EBD is malfunctioning, the rear wheels can
lock, e.g. under full braking. This increases the risk of skidding and an accident.
You should therefore adapt your driving style
to the different handling characteristics. Have the brake system checked at a qualified spe-
cialist workshop.
Observe information regarding indicator and
warning lamps (Y page 277) as well as display
messages (Y page 247). 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 182) and hill start
assist (Y page 139). Active Brake Assist with cross-traffic
function
General information i
Pay attention to the important safety notes
in the "Driving safety systems" section
(Y page 66).
Active Brake Assist with cross-traffic function
can help you to minimize the risk of a collision
with a vehicle in front or a pedestrian and reduce
the effects of such a collision. If the Active Brake
Assist with cross-traffic function detects a risk
of collision, you will be warned visually and
acoustically and, if necessary, your brake appli- cation will be assisted according to the situa-
tion. If you do not react, the system can also
react by braking automatically. In the event of a detected risk of collision due to crossing traffic,you will also be visually and acoustically warned
as well as assisted by the brake boosting effect
according to the situation.
Active Brake Assist with cross-traffic function is
only available in vehicles with the Driving Assis- tance Plus package.
For Active Brake Assist with cross-traffic func-
tion to assist you when driving, the radar sensor
system and the camera system must be opera-
tional. 72
Driving safety systemsSafety
Up to a speed of approximately 44 mph
(70 km/h) the Active Brake Assist with cross-
traffic function assists you with braking in haz-
ardous situations with:
R stationary obstacles in the path of the vehicle,
e.g. stopped or parked vehicles
R stationary pedestrians in the path of the vehi-
cle
R obstacles crossing your path that move in the
detection range of the sensors and are detec- ted
X Keep the brake pedal depressed until the
emergency braking situation is over.
ABS prevents the wheels from locking.
You can prevent the intervention of Active Brake Assist with cross-traffic function at any time by:
R depressing the accelerator pedal further
R activating kickdown
R releasing the brake pedal
The braking application of Active Brake Assist
with cross-traffic function is ended automati-
cally if:
R you maneuver to avoid the obstacle
R there is no longer a risk of collision
R there is no longer an obstacle detected in
front of your vehicle 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
Important safety notes i
Observe the "Important safety notes" sec-
tion (Y page 66). No steering assistance is provided from STEER
CONTROL, if:
R ESP ®
is deactivated
R ESP ®
is malfunctioning
R the steering is malfunctioning
If ESP ®
is malfunctioning, you will be assisted
further by the electrical power steering. Protection against theft
Immobilizer
X To activate with the SmartKey: remove the
SmartKey from the ignition lock.
X To activate with KEYLESS-GO: switch the
ignition off and open the driver's door.
X To deactivate: switch on the ignition.
The immobilizer prevents your vehicle from
being started without the correct SmartKey.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Anyone
can start the engine if a valid SmartKey has been left inside the vehicle.
i The immobilizer is always deactivated when
you start the engine.
In the event that the engine cannot be started (yet the vehicle's battery is charged), the sys-
tem is not operational. Contact an authorized Mercedes-Benz Center or call
1-800 FOR-MERCEDES (in the USA) or
1-800-387-0100 (in Canada). ATA (anti-theft alarm system) Protection against theft
75Safety Z
X
To arm: lock the vehicle with the SmartKey or
KEYLESS-GO.
Indicator lamp 0043flashes. The alarm system
is armed after approximately 15 seconds.
X To switch off using the SmartKey: unlock
the vehicle with the SmartKey.
or X Insert the SmartKey into the ignition lock.
X To switch off using KEYLESS-GO: unlock
the vehicle with KEYLESS-GO.
or X Press the Start/Stop button on the dash-
board. The SmartKey must be inside the vehi-
cle.
A visual and audible alarm is triggered if the
alarm system is armed and you open:
R a door
R the vehicle with the mechanical key
R the tailgate
R the hood
X To switch the alarm off with the Smart-
Key:
press the 0036or0037 button on the
SmartKey.
The alarm is stopped.
or X Insert the SmartKey into the ignition lock.
The alarm is stopped.
X To stop the alarm using KEYLESS-GO:
grasp the outside door handle. The SmartKey
must be outside the vehicle.
The alarm is stopped.
or X Press the Start/Stop button on the dash-
board. The SmartKey must be inside the vehi-
cle.
The alarm is stopped.
The alarm is not switched off, even if you close
the open door that triggered it, for example. i
If the alarm continues for more than
30 seconds, the mbrace emergency call sys-
tem automatically notifies the Customer
Assistance Center. This is done either by text
message or data connection. The emergency call system sends the message or data provi-ded that:
R you have subscribed to the mbrace service.
R the mbrace service has been activated
properly.
R the necessary mobile phone network is
available. 76
Protection against theftSafety
SmartKey
Important safety notes
G
WARNING
If children are left unsupervised in the vehicle, they could:
R open the doors, thus endangering other
people or road users.
R get out and disrupt traffic.
R operate the vehicle's equipment.
Additionally, children could set the vehicle in
motion if, for example, they:
R release the parking brake.
R shifting the automatic transmission out of
park position P
R Start the engine.
There is a risk of an accident and injury.
When leaving the vehicle, always take the
SmartKey with you and lock the vehicle. Never
leave children or animals unattended in the
vehicle. Always keep the SmartKey out of
reach of children. G
WARNING
If you attach heavy or large objects to the
SmartKey, the SmartKey could be uninten-
tionally turned in the ignition lock. This could
cause the engine to be switched off. There is a risk of an accident.
Do not attach any heavy or large objects to the
SmartKey. Remove any bulky key rings before
inserting the SmartKey into the ignition lock.
! Keep the SmartKey away from strong mag-
netic fields. Otherwise, the remote control
function could be affected.
Strong magnetic fields can occur in the vicin- ity of powerful electrical installations.
Do not keep the SmartKey: R with electronic devices, e.g. a mobile phone
or another SmartKey.
R with metallic objects, e.g. coins or metal foil.
R inside metallic objects, e.g. a metal case.
This can affect the functionality of the Smart- Key. Do not keep the KEYLESS-GO or KEYLESS-GO
Start function key in the temperature-controlled
cup holder. Otherwise, the KEYLESS-GO or KEY- LESS-GO Start function key will not be detected.
Vehicles with KEYLESS-GO start function: do
not keep the SmartKey in the cargo compart-
ment. Otherwise, the SmartKey may not be
detected, e.g. when starting the engine using
the Start/Stop button. SmartKey functions
0043
0037 To lock the vehicle
0044 0054 To open/close the tailgate
0087 0036 To unlock the vehicle
X To unlock centrally: press the0036button.
If you do not open the vehicle within approx-
imately 40 seconds of unlocking:
R the vehicle is locked again.
R anti-theft protection is reactivated.
X To lock centrally: press the0037button.
The SmartKey centrally locks and unlocks the
following components:
R the doors
R the tailgate
R the fuel filler flap
The turn signals flash once when unlocking and three times when locking.
You can also set an audible signal to confirm
that the vehicle has been locked. The audible
signal can be activated and deactivated using
the on-board computer (Y page 240).
You will receive visual and acoustic locking con-
firmation if all components were able to be
locked. SmartKey
77Opening and closing Z
If activated in the multimedia system, the loca-
tor lighting also lights up in the dark (see the
Digital Operator's Manual).
X To open the tailgate automatically from
outside the vehicle:
press and hold the0054
button until the tailgate opens.
Vehicles with KEYLESS-GO: X To close the tailgate automatically from
outside the vehicle:
if the SmartKey is loca-
ted in the immediate vicinity of the vehicle,
press the 0054button on the SmartKey.
When the tailgate closes you can then release
the button. KEYLESS-GO
General notes Bear in mind that the engine can be started by
any of the vehicle occupants if there is a KEY-
LESS-GO key in the vehicle (Y page 137).
Locking/unlocking centrally You can start, lock or unlock the vehicle using
KEYLESS-GO. To do this, you only need carry the
SmartKey with you. You can combine the func-
tions of KEYLESS-GO with those of a conven-
tional SmartKey. Unlock the vehicle by using
KEYLESS-GO, for instance, and lock it using the 0037 button on the SmartKey.
The driver's door and the door at which the han- dle is used, must both be closed. The SmartKey
must be outside the vehicle. When locking or
unlocking with KEYLESS-GO, the distance
between the SmartKey and the corresponding
door handle must not be greater than 3 ft (1 m).
KEYLESS-GO checks whether a valid SmartKey
is in the vehicle by periodically establishing a
radio connection between the vehicle and the
SmartKey. This happens:
R when starting the engine
R while driving
R when the external door handles are touched
R during convenience closing X
To unlock the vehicle: touch the inner sur-
face of the door handle.
X To lock the vehicle: touch sensor surface 0043
or 0044.
Make sure that you do not touch the inner
surface of the door handle.
X Convenience closing feature: touch
recessed sensor surface 0044for an extended
period.
Further information on the convenience closing
feature (Y page 90).
If you pull on the handle of the tailgate, only the cargo compartment of the vehicle is unlocked.
Deactivating and activating If you do not intend to use a SmartKey for an
extended period of time, you can deactivate the
KEYLESS-GO function of the SmartKey. The
SmartKey will then use very little power, thereby conserving battery power. For the purposes of
activation/deactivation, the vehicle must not be
nearby.
X To deactivate: press the0037button on the
SmartKey twice in rapid succession.
The battery check lamp of the SmartKey
flashes twice briefly and lights up once, KEY-
LESS-GO is deactivated (Y page 80).
X To activate: press any button on the Smart-
Key.
or X Insert the SmartKey into the ignition lock.
KEYLESS-GO and all of its associated features are available again. 78
SmartKeyOpening and closing