
and to have any malfunctioning air bagsrepaired. This will help to make sure the air bagscontinue to perform their protective function forthe vehicle occupants in the event of a crash.
GWARNING
Emergency Tensioning Devices that have
deployed pyrotechnically are no longer opera-
tional and are unable to perform their inten-
ded protective function. This poses an
increased risk of injury or even fatal injury.
Have pyrotechnically triggered Emergency
Tensioning Devices replaced immediately at a
qualified specialist workshop.
An electric motor is used by PRE-SAFE®to trig-ger the tightening of the seat belt in hazardoussituations. This procedure is reversible.
If Emergency Tensioning Devices are triggeredor air bags are deployed, you will hear a bang,and some powder may also be released. The urestraint system warning lamp lights up.
Only in rare cases will the bang affect your hear-ing. The powder that is released generally doesnot constitute a health hazard, but it may causeshort-term breathing difficulties in people withasthma or other respiratory problems. Providedit is safe to do so, you should leave the vehicleimmediately or open the window in order to pre-vent breathing difficulties.
Air bags and pyrotechnic Emergency TensioningDevices (ETDs) contain perchlorate material,which may require special handling and regardfor the environment. National guidelines mustbe observed during disposal. In California, seewww.dtsc.ca.gov/HazardousWaste/Perchlorate/index.cfm.
Method of operation
During the first stage of a collision, the restraintsystem control unit evaluates important physi-cal data relating to vehicle deceleration or accel-eration, such as:
Rduration
Rdirection
Rintensity
Based on the evaluation of this data, therestraint system control unit triggers the Emer-gency Tensioning Devices during a head-on orrear-end collision.
An Emergency Tensioning Device can only betriggered, if:
Rthe ignition is switched on
Rthe components of the restraint system areoperational. You can find further informationunder "Restraint system warning lamp"(Ypage 44)
Rthe seat belt buckle tongue has engaged inthe belt buckle of the respective front seat
The Emergency Tensioning Devices in the rearpassenger compartment are triggered inde-pendently of the lock status of the seat belts.
If the restraint system control unit detects amore severe accident, further components ofthe restraint system are activated independ-ently of each other in certain frontal collisionsituations:
RFront air bags and driver's knee bag
RWindow curtain air bag, if the system deter-mines that deployment can offer additionalprotection to that provided by the seat belt
Depending on the person in the front-passengerseat, the front-passenger front air bag is eitherdisabled or enabled. The front-passenger frontair bag can be deployed in an accident only if thePASSENGER AIR BAG OFF indicator lamp is off.Observe the information on the PASSENGER AIRBAG indicator lamps (Ypage 44).
Your vehicle has two-stage front air bags. At thefirst deployment threshold the front air bag fillswith gas. If the second deployment threshold isthen reached within a few milliseconds, the frontair bag is filled with the maximum quantity ofgas.
The activation threshold of the Emergency Ten-sioning Devices and the air bags is determinedby evaluating the rate of vehicle deceleration oracceleration which occurs at various points inthe vehicle. This process is pre-emptive innature. Deployment should take place in goodtime at the start of the collision.
The rate of vehicle deceleration or accelerationand the direction of the force are essentiallydetermined by:
Rthe distribution of forces during the collision
Rthe collision angle
Rthe deformation characteristics of the vehicle
Rthe characteristics of the object with whichthe vehicle has collided
Factors which can only be seen and measuredafter a collision has occurred do not play a deci-sive role in the deployment of an air bag. Nor do
56Occupant safety
Safety

PRE-SAFE®takes the following measuresdepending on the hazardous situation detected:
Rthe front seat belts are pre-tensioned.
Rif the vehicle skids, the side windows and thesliding sunroof are closed.
Rvehicles with the memory function for thefront-passenger seat: the front-passengerseat is adjusted if it is in an unfavorable posi-tion.
If the hazardous situation passes without result-
ing in an accident, PRE-SAFE®slackens the belt
pre-tensioning. All settings made by PRE-SAFE®
can then be reversed.
If the seat belt pre-tensioning is not reduced:
XMove the seat backrest or seat back slightlywhen the vehicle is stationary.The seat belt pre-tensioning is reduced andthe locking mechanism is released.
The seat-belt adjustment is an integral part of
the PRE-SAFE®convenience function. Informa-tion about the convenience function can befound under "Belt adjustment" (Ypage 47).
PRE-SAFE®PLUS (anticipatory occu-
pant protection system PLUS)
Introduction
PRE-SAFE®PLUS is only available in vehicleswith the Driving Assistance package.
Using the radar sensor system, PRE-SAFE®
PLUS is able to detect that a frontal or rear-endcollision is imminent. In certain hazardous sit-
uations, PRE-SAFE®PLUS takes pre-emptivemeasures to protect the vehicle occupants.
Important safety notes
The intervention of PRE-SAFE®PLUS cannotprevent an imminent collision.
The driver is not warned about the intervention
of PRE-SAFE®PLUS.
PRE-SAFE®PLUS does not intervene:
Rif the vehicle is backing up
Rwhen the vehicle is towing a trailer and thereis a risk of a rear-end collision
When driving, or when parking or exiting a park-ing space using Active Parking Assist, PRE-
SAFE®PLUS will not apply the brakes.
Function
PRE-SAFE®PLUS intervenes in certain situa-tions if the radar sensor system detects animminent frontal or rear-end collision.
PRE-SAFE®PLUS takes the following measuresdepending on the hazardous situation detected:
Rif the radar sensor system detects that ahead-on collision is imminent, the seat beltsare pre-tensioned.
Rif the radar sensor system detects that a rear-end collision is imminent:
-the brake pressure is increased if the driverapplies the brakes when the vehicle is sta-tionary.
-the seat belts are pre-tensioned.
The PRE-SAFE®PLUS braking application is can-celed:
Rif the accelerator pedal is depressed when agear is engaged
Rif the risk of a collision passes or is no longerdetected
Rif Active Distance Assist DISTRONIC indicatesan intention to intervene
If the hazardous situation passes without result-ing in an accident, the original settings arerestored.
Automatic measures after an acci-
dent
Immediately after an accident, the followingmeasures are implemented, depending on thetype and severity of the impact:
Rthe hazard warning lamps are switched on
Rthe emergency lighting is activated
Rthe vehicle doors are unlocked
Rthe front side windows are lowered
Rvehicles with a memory function: the electri-cally adjustable steering wheel is raised whenthe driver's door is opened
Rthe engine is switched off and the fuel supplyis cut off
Rvehicles with mbrace: automatic emergencycall
58Occupant safety
Safety

Children in the vehicle
Important safety notes
Accident statistics show that children securedin the rear seats are safer than children securedin the front-passenger seat. For this reason,Mercedes-Benz strongly advises that you installa child restraint system on a rear seat. Childrenare generally better protected there.
If a child younger than twelve years old andunder 5 ft (1.50 m) in height is traveling in thevehicle:
Ralways secure the child in a child restraintsystem suitable for Mercedes-Benz vehicles.The child restraint system must be appropri-ate to the age, weight and size of the child.
Rbe sure to observe the instructions and safetynotes in this section in addition to the childrestraint system manufacturer's installationinstructions.
Ralways observe the instructions and safetynotes on the "Occupant classification system(OCS)". (Ypage 51)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking positionP.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
GWARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
GWARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro-
tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Always ensure that all vehicle occupants havetheir seat belts fastened correctly and are sittingproperly. Particular attention must be paid tochildren.
Observe the safety notes on the seat belt(Ypage 45)and the notes on correct use of seatbelts (Ypage 46).
A booster seat may be necessary to achieveproper seat belt positioning for children over40 lbs(18 kg) until they reach a height where athree-point seat belt can be properly fastenedwithout a booster seat.
Special seatbelt retractor
GWARNING
If the seat belt is released while driving, the
child restraint system will no longer be
secured properly. The special seat belt retrac-
tor is disabled and the inertia real draws in a
portion of the seat belt. The seat belt cannot
be immediately refastened. There is an
increased risk of injury, possibly even fatal.
Stop the vehicle immediately, paying atten-
tion to road and traffic conditions. Reactivate
the special seat belt retractor and secure the
child restraint system properly.
All seat belts in the vehicle, except the driver'sseat belt, are equipped with a special seat beltretractor. When activated, the special seat beltretractor ensures that the seat belt cannotslacken once the child seat is secured.
Children in the vehicle59
Safety
Z

tem and the vehicle. This helps reduce the risk ofinjury even further. If the child restraint systemis equipped with a Top Tether belt, this shouldalways be used.
Important safety notes
GWARNING
If the rear seat backrests are not locked, they
could fold forwards in the event of an acci-
dent, heavy braking or sudden changes of
direction. As a result, child restraint systems
cannot perform their intended protective
function. Rear seat backrests that are not
locked can also cause additional injuries, e.g.
in the event of an accident. This poses an
increased risk of injury or even fatal injury.
Always lock rear seat backrests after instal-
ling a Top Tether belt. Observe the lock veri-
fication indicator.
If the rear seat backrest is not engaged andlocked, this will be shown in the multifunctiondisplay in the instrument cluster.
Top Tether anchorages
Top Tether anchorage points

You can thus avoid the risks that could arise asa result of:
Ran incorrectly categorized person in the front-passenger seat
Rdeactivating the front passenger front air bagunintentionally
Rthe unsuitable positioning of the childrestraint system, e.g. too close to the dash-board
Rearward-facing child restraint system
If circumstances require you to secure a child ina rearward-facing child restraint system on thefront-passenger seat, always make sure that thefront passenger front air bag is deactivated.Only if the PASSENGER AIR BAG OFF indicatorlamp is lit continuously (Ypage 44), is the frontpassenger front air bag deactivated.
Always observe the child restraint system man-ufacturer's installation and operating instruc-tions.
Forward-facing child restraint system
If it is absolutely necessary to install a forward-facing child restraint system on the front-passenger seat, always move the front-passenger seat as far back as possible. Fullyretract the seat cushion length. The entire baseof the child restraint system must always rest onthe seat cushion of the front-passenger seat.The backrest of the child restraint system mustlie as flat as possible against the backrest of thefront-passenger seat. The child restraint systemmust not touch the roof or be subjected to a loadby the head restraint. Adjust the angle of theseat backrest and the head restraint positionaccordingly. Always make sure that the shoul-der belt strap is correctly routed from the vehi-cle belt outlet to the shoulder belt guide on thechild restraint system. The shoulder belt strapmust be routed forward and down from the vehi-cle belt outlet. If necessary, adjust the vehiclebelt outlet and the front-passenger seat accord-ingly.
Always observe the child restraint system man-ufacturer's installation and operating instruc-tions.
Child-proof locks
Important safety notes
GWARNING
If children are traveling in the vehicle, they
could:
Ropen doors, thus endangering other people
or road users
Rexit the vehicle and be caught by oncoming
traffic
Roperate vehicle equipment and become
trapped
There is a risk of an accident and injury.
Always activate the child-proof locks and
override feature if children are traveling in the
vehicle. When leaving the vehicle, always take
the key with you and lock the vehicle. Never
leave children unattended in the vehicle.
Override feature for:
Rthe rear doors (Ypage 64)
Rthe rear side windows (Ypage 64)
GWARNING
If you leave children unsupervised in the vehi-
cle, they could set it in motion by, for example:
Rrelease the parking brake.
Rshift the automatic transmission out of the
parking positionP.
Rstart the engine.
In addition, they may operate vehicle equip-
ment and become trapped. 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 unsupervised in the vehicle.
GWARNING
If persons, particularly children are subjected
to prolonged exposure to extreme heat or
cold, there is a risk of injury, possibly even
fatal. Never leave children unattended in the
vehicle.
Children in the vehicle63
Safety
Z

GWARNING
If the child restraint system is subjected to
direct sunlight, parts may get very hot. Chil-
dren may burn themselves on these parts,
particularly on the metal parts of the child
restraint system. There is a risk of injury.
If you leave the vehicle, taking the child with
you, always ensure that the child restraint
system is not exposed to direct sunlight. Pro-
tect it with a blanket, for example. If the child
restraint system has been exposed to direct
sunlight, let it cool down before securing the
child in it. Never leave children unattended in
the vehicle.
Child-proof locks for the rear doors
You secure each door individually with the child-proof locks on the rear doors. A door securedwith a child-proof lock cannot be opened frominside the vehicle. When the vehicle is unlocked,the door can be opened from the outside.
XTo activate:press the child-proof lock leverup in the direction of arrow C.
XMake sure that the child-proof locks are work-ing properly.
XTo deactivate:press the child-proof locklever down in the direction of arrow D.
Child-proof locks for the rear side win-
dows
XTo enable/disable:press button D.If indicator lamp Cis lit, operation of the rearside windows is disabled. Operation is onlypossible using the switches in the driver'sdoor. If indicator lamp Cis off, operation ispossible using the switches in the rear com-partment.
Pets in the vehicle
GWARNING
If you leave animals unsupervised or unse-
cured in the vehicle, they may press buttons
or switches, for instance.
In this way, animals may:
Ractivate vehicle equipment and become
trapped, for example
Rswitch systems on or off and thereby
endanger other road users
Furthermore, unsecured animals may be flung
around inside the vehicle in the event of an
accident or abrupt steering or braking maneu-
ver, and thereby injure vehicle occupants.
There is a risk of accident and injury.
Never leave animals unattended in the vehi-
cle.
Always secure animals properly when driving,
for instance with a suitable pet carrier.
64Pets in the vehicle
Safety

Driving safety systems
Overview of driving safety systems
In this section, you will find information aboutthe following driving safety systems:
RABS (Anti-lockBrakingSystem)(Ypage 65)
RBAS (BrakeAssistSystem) (Ypage 66)
RActive Brake Assist (Ypage 66)
RESP®(ElectronicStabilityProgram)(Ypage 68)
REBD (ElectronicBrake forceDistribution)(Ypage 72)
RADAPTIVE BRAKE (Ypage 72)
RActive Brake Assist with cross-traffic function(Ypage 72)
RSTEER CONTROL (Ypage 75)
Important safety notes
If you fail to adapt your driving style or if you areinattentive, the driving safety systems can nei-ther reduce the risk of an accident nor overridethe laws of physics. Driving safety systems aremerely aids designed to assist driving. You areresponsible for maintaining the distance to thevehicle in front, for vehicle speed, for braking ingood time, and for staying in lane. Always adaptyour driving style to suit the prevailing road andweather conditions and maintain a safe distancefrom the vehicle in front. Drive carefully.
The driving safety systems described only workas effectively as possible when there is ade-quate contact between the tires and the roadsurface. Pay particular attention to the informa-tion regarding tires, recommended minimumtire tread depths etc. in the "Wheels and tires"section (Ypage 330).
In wintry driving conditions, always use wintertires (M+S tires)and if necessary, snow chains.Only in this way will the driving safety systemsdescribed in this section work as effectively aspossible.
ABS (Anti-lock Braking System)
General information
ABS regulates brake pressure in such a way thatthe wheels do not lock when you brake. Thisallows you to continue steering the vehicle whenbraking.
The %ABS warning lamp in the instrumentcluster lights up when the ignition is switchedon. 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 youonly brake gently.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 65).
GWARNING
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 alsobecome inoperative. Observe the informationon the ABS warning lamp (Ypage 259) and dis-play messages which may be shown in theinstrument cluster (Ypage 228).
Braking
XIf ABS intervenes:continue to depress thebrake pedal vigorously until the braking sit-uation is over.
XTo make a full brake application:depressthe brake pedal with full force.
If ABS intervenes when braking, you will feel apulsing in the brake pedal.
The pulsating brake pedal can be an indicationof hazardous road conditions, and functions as areminder to take extra care while driving.
Driving safety systems65
Safety
Z

BAS (Brake Assist System)
General information
BAS operates in emergency braking situations.If you depress the brake pedal quickly, BASautomatically boosts the braking force, thusshortening the stopping distance.
Important safety notes
iObserve the "Important safety notes" sec-tion (Ypage 65).
GWARNING
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
XKeep the brake pedal firmly depressed untilthe emergency braking situation is over.ABS prevents the wheels from locking.
The brakes will function as usual once yourelease the brake pedal. BAS is deactivated.
Active Brake Assist
General information
iObserve the "Important safety notes" sec-tion (Ypage 65).
Active Brake Assist consists of a distance warn-ing function with an autonomous braking func-tion and Adaptive Brake Assist.
Active Brake Assist can help you to minimize therisk of a collision with the vehicle traveling infront or reduce the effects of such a collision.
If Active Brake Assist detects that there is a riskof collision, you will be warned visually andacoustically. If you do not react to the visual andaudible collision warning, autonomous brakingcan be initiated in critical situations. If you applythe brake yourself in a critical situation, Adap-tive Brake Assist of the Active Brake Assist sys-tem supports you.
Important safety notes
In particular, the detection of obstacles can beimpaired if:
RThere is dirt on the sensors or anything elsecovering the sensors
RThere is snow or heavy rain
RThere is interference by other radar sources
RThere are strong radar reflections, for exam-ple in parking garages
RA narrow vehicle is traveling in front, e.g. amotorbike
RA vehicle is traveling in front on a different line
RYou are driving a new vehicle or servicing onthe Active Brake Assist system has just beencarried out
Observe the important safety notes in the"Breaking-in notes" section (Ypage 130).
Following damage to the front end of the vehicle,have the configuration and operation of theradar sensor checked at a qualified specialistworkshop. This also applies to collisions at slowspeeds where there is no visible damage to thefront of the vehicle.
Activating/deactivating
Active Brake Assist is automatically active afterswitching on the ignition.
You can activate or deactivate Active BrakeAssist (Ypage 220) in the on-board computer.When deactivated, the distance warning func-tion and the autonomous braking function arealso deactivated.
If Active Brake Assist is deactivated, the