Airbag system
123
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
When are the airbags deployed?The airbag system is designed in such a
way that the driver and the front passenger
airbag* are deployed in the event of a
frontal collision of major severity
.
In the case of a
violent side crash
, the side airbag* in the front seat and the head
airbag* on the side on which the collision occurs are deployed. It is also possible under certain special accident situations that the front as well as the side airbags and head airbags* are deployed at the same time. The airbags
are not deployed
in the case of
minor
frontal and side collisions, rear-end
collisions, tilting of the ve
hicle and vehicle rollover.
Deployment factors It is not possible to state globally which
deployment conditions apply to the airbag
system in every situation as the circumstances which exist in the case of accidents vary greatly. An important role in this case, for ex
ample, is played by factors such as the type
of object against which the vehicle impacts (h
ard, soft), the angle of impact, the vehicle
speed etc. A decisive factor for the deployment of the airbags is the deceleration which occurs during a collision. The control unit analyses
the nature of the collision and activates the
relevant restraint system. If the vehicle deceleration which occurs and is measured during the collision remains below the prescribed reference values specified in the control unit, the airbags are no
t deployed although the vehicle may well suffer severe
damage to the bodywork as a consequence of the accident. The airbags are not deployed if:
ignition is switched off;
a minor frontal collision;
a minor side collision;
a rear-end collision;
Rollover of the vehicle.Note
A grey white or red, non harmful gas is released when airbag is inflated. This is
perfectly normal and is not an indi
cation of a fire in the vehicle.
In the event of an accident in which the airbags are deployed: the interior lighting comes on (if the swit
ch for the interior light is in the door
contact position), the hazard warning li
ght is switched on;
All the doors are unlocked.
Front airbagsDescription of the front airbags The airbag system is not a su
bstitute for the seat belt!
Fig. 114 Driver airbag in the steering wheel
/ front passenger airbag in the dash panel
The front airbag for the driver is housed in the steering wheel
fig. 114
- left. The front
airbag for the front passenger* is housed in the dash panel above the storage compart- ment
fig. 114
- right. The installation positions are each marked with the “AIRBAG”
logo. The front airbag system, in combination with
three-point safety belts, offers additional
protection for the head and chest area of the driver and front passenger in the event of a frontal collision of major severity
in “Important safety information regarding
the front airbag system” on page 124. The airbag is not a substitute for the seat
belt, but is part of the complete passive
vehicle safety concept.
Please note that an airbag can only offer you optimal
protection in combination with a seat belt which is fastened
.
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Airbag system
124
Apart from their normal protective function, a further task of the
seat belts
is to also
hold the driver and front passenger in a correct seated position in the event of a frontal collision so as to enable the front ai
rbags to offer the maximum protection.
You should therefore always fasten the seat be
lts, not only because this is required by
law, but also for safety reasons and for your own protection
page 117, “Why seat
belts?”.
Caution
The dash panel must be replaced after the front passenger airbag has been deployed.Function of the front airbags Risk of injury to the upper part of the body is reduced by fully inflated side airbags.The airbag system is designed in such a way that the driver and front passenger airbag* are deployed in the event of a frontal collision of major severity. In certain accident situations, the front, side and head airbag are simultaneously deployed. If the airbags are deployed, the airbags are filled with a propellant gas and inflated in front of the driver and front passenger
fig. 115
. The airbags inflate in fractions of a
second and at a high speed in order to be able
to offer that additional protection in the
event of an accident. The movement of the
driver and of the front passenger is cush-
ioned when they make contact with the fully
inflated airbag and the risk of injury to
head and chest is thus reduced. The specially developed airbag allows the gas
to flow out of the inflated airbag in a
controlled manner (depending on the load of
the particular car occupant) in order to
cushion head and chest areas. The airbag then
deflates subsequently to such an extent,
after an accident, to again provide a clear view forward. A grey white, non harmful gas is released when airbag is inflated. This is perfectly normal and is not an indicati
on of a fire in the vehicle.
The airbag develops enormous forces when triggered, which can lead to injuries if the sitting position or seated position is not correct
in “Important safety information
regarding the front airbag system”.Important safety information regarding the front airbag system Correct use of the airbag system cons
iderably reduces the risk of injury!
WARNING
Never transport children on the front seat of a vehicle without using a
proper restraint system. If airbags are de
ployed in the event of an accident, the
child might suffer severe
or even fatal injuries!
For the driver and front passenger it is important to maintain a distance of
at least 25 cm from the steering wheel or dash panel
fig. 116
. Not main-
taining this minimum distance will mean that the airbag system will not be able to properly protect you - hazard! The front seats and the head restraints must always also be correctly adjusted to match the body size of the occupant.
Fig. 115 Inflated airbags
Fig. 116 Safe distance to steering wheel
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Airbag system
125
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
It is essential to always switch off
page 128, “Deactivating airbags” the
front passenger airbag when attaching a child safety seat on the front passenger seat where the child is seated
with its back facing in direction of
travel (in some countries also
when the child is facing the direction of travel). If
this is not done, there is a risk of the ch
ild suffering severe or even fatal injuries
if the front passenger airbag is deploy
ed. In certain countries national legal
provisions also require that the side or
head passenger airbags be deactivated.
When transporting a child on the front passenger seat, please comply with the appropriate national regu
lations regarding the use of child safety seats.
There must not by any further persons, animals or objects positioned
between the front seated occupants and
the deployment area of the airbag.
The steering wheel and the surface of th
e airbag module in the dash panel
on the passenger side must not be stuck
onto, covered or modified in any other
way. These parts should only be cleaned with a dry cloth or a cloth moistened with water. No objects such as cup holders, mobile phone mounts, etc. may be attached to the covers of the airbag modules or be located within the imme- diate area.
No modifications of any kind may be
made to parts of the airbag system.
Any work on the airbag system includ
ing installing and removing system
components because of other repair wo
rk (e.g. removing the steering wheel)
must only be carried out by a specialist garage.
Never carry out changes on the front bumper or on the body.
Never place any objects on the surface of the dash panel on the front
passenger side.
Side airbags*Description of side airbags The side airbag increases protection
of the passenger concerned in the
case of a side impact.The side airbags are housed in the upholstery of the seat backrests of the front seats and are marked with the lettering “AIRBAG”
fig. 117
on the middle part.
The side airbag system in combination with the three-point seat belts, offers additional protection for the upper area of the body
(chest, stomach and pelvis) in the event of
severe side collisions
in “Important safety information on the side airbag” on
page 126. Apart from their normal protective function, a further task of the
seat belts
is to also
hold the driver and front pass
enger in a correct seated position in the event of a side
collision so as to enable the side ai
rbags to offer the maximum protection.
You should therefore always fasten the seat belts, not only because this is required by law, but also for safety reasons and for your own protection
page 117, “Why seat
belts?”.
WARNING (continued)
Fig. 117 Driver seat: Installation posi- tion of airbag
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Airbag system
128
Important safety information on the head airbag Correct use of the airbag system cons
iderably reduces the risk of injury!
WARNING
It is essential to always switch off
page 128 the front passenger airbag
when attaching a child safety seat on th
e front passenger seat where the child is
seated with its back facing in direction of travel (in some countries also when the child is facing the direction of travel). If this is not done, there is a risk of the child suffering severe or even fatal inju
ries if the front passenger airbag is
deployed. In certain countries national legal provisions also require that the side or head passenger airbags be deac
tivated. When transporting a child on
the front passenger seat, pl
ease comply with the appropriate national regula-
tions regarding the use of child safety seats.
There must not be any objects in the deployment area of the head airbags
which might prevent the airbag
s from inflating properly.
Only hang light items of clothing on the clothes hooks to the vehicle. Never
leave any heavy or sharp-edged objects in
the pockets of the
items of clothing.
In addition, it is not permitted to use clothes hangers for hanging up items of clothing.
There must not be any other persons (e
.g. children) or animals between the
car occupant and the deployment area of the head airbag. In addition, none of the occupants should lean their head out of the window when driving, or extend their arms and hands out of the window.
The sun visors must not be swivelled to the side windows into the deploy-
ment area of the head airbags if any ob
jects, such as ball-point pens etc. are
attached to them. This might result in
injuries to the occupants if the head
airbag is deployed.
Installing impermissible accessories in the area of the head airbags may
considerably impair the protection offered
by the head airbag in the event of it
being deployed. When the deployed head
airbag is inflated, parts of the acces-
sories fitted may in certain circumstances be thrown into the interior of the car and cause injuries to the occupants
page 184.
Any work on the head airbag system
including installing and removing
system components because
of other repair work (e.g. removing headliner)
must only be carried out by a specialist garage.
Deactivating airbagsDeactivating airbags If any airbags have been deactivated, switch them on again as soon as possible so that they are able to ag
ain provide their proper protection.
There is the technical means installed within your vehicle to switch off the front, side* or head* airbag (take out of commission). This is why you should have the deactivation
of the airbags carried out by a specialist
garage. On vehicles equipped with the switch for deactivation of the airbags, you can deacti- vate the front passenger airbag
by means of this switch
page 129.
Deactivation of the airbag is envisaged only for particular instances, such as if:
in exceptional circumstances
, it is necessary to use a child safety seat on the front
passenger seat, where the child is seated with
its back facing in
direction of travel
page 130, “Important safety information re
garding the use of child safety seats”;
you are not able to maintain the distance of at least 25 cm between middle of
steering wheel and chest, despite the
driver seat being correctly adjusted;
special attachments are required in the area of the steering wheel because of a
physical disability;
you have installed other seats (e.g. orthopaedic seats without side airbags).
Monitoring the airbag system The functionality of the airbag system is al
so monitored electronically when one airbag
has been switched off. If the airbag was switched off using diagnostic equipment:
The airbag indicator light lights up for 3 seconds each time the ignition is switched
on and then flashes after that for about 12 seconds. If the airbag was switched off using the airbag switch* on the side of the dash panel:
the airbag indicator light in the instrume
nt cluster comes on for about 3 seconds
each time the igniti
on is switched on;
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Intelligent Technology
137
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Driving TipsIntelligent TechnologyElectronic stability programme (ESP)*GeneralGeneral The ESP aids you in maintaining control of
your vehicle in situations in which the
vehicle is driving at its dynamic limits, such as
entering a curve fast. The risk of skidding
is reduced and your vehicle thus offers greater driving stability depending on the conditions of the road surface. The system operates at all speeds. The following systems are integrated into the electronic stability programme:
Electronic Differential Lock (EDL);
Traction control system (TCS);
Antilock brake system (ABS);
Brake Assist;
Uphill Start Assist.
Operating principle The ESP switches on automati
cally when the engine is started and then conducts a
self-test. The ESP control unit processes data from the individual systems. It also proc- esses additional measurement data which are supplied by highly sensitive sensors: the rotational velocity of the vehicle about its ve
rtical axis, the lateral acceleration of the
vehicle, the braking pressure and the steering angle. The direction which the driver wishes to take is determined based on the steering angle and the speed of the vehicle and is co
nstantly compared wi
th the actual behav-
iour of the vehicle. If differences exist, such
as the vehicle beginning to skid, the ESP will
automatically brake the appropriate wheel. The car is stabilised again by the forces wh
ich take effect when the wheel is braked.
Intervention into the brake system takes place primarily on the outer front wheel of a vehicle which tends to oversteer (tendency fo
r the rear of the vehicle to break away)
while occurs this is on the inner rear wh
eel of a vehicle whic
h tends to understeer
(tendency to shift out of the curve). This braking control cycle is accompanied by noises. If the ESP helps to stabilise the vehicle (f
or example when applying and releasing a
braking force to an individual wheel), then the indicator light
flashes.
The ESP system cannot be switched off, only
the TCS system can be switched off by
pressing the button
page 138, fig. 130
. The warning light
page 31 lights up if
the TCS system is switched off. The warning light
lights up permanently if there is a fault in the ESP system.
The fact that the ESP system operates together with the ABS means that the ESP warning light will also come on if the ABS system is not operating properly. If the warning light
comes on immediately after starting the engine, the ESP system
can be switched off for technical reasons. In
this case, the ESP system can be switched
on again by switching the igni
tion on and off. If the warning light goes out, the ESP
system is fully functional again.
WARNING
It is also not possible for the ESP to overcome the physical limits of the vehicle. Even if a vehicle fitted with ESP you should still always adapt your style of driving to the condition of the road surfac
e and the traffic situation. This partic-
ularly applies when driving on slippery
and wet roads. The increased safety
offered must not tempt you to take greater risks than otherwise - risk of an acci- dent!
Note
All four wheels must be fitted with the same tyres in order to achieve problem-free
operation of the ESP. Differing rolling circum
ferences of the tyres can lead to an unde-
sirable reduction in the engine output.
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Intelligent Technology
140
Low brake fluid level An insufficient level of brake fluid may result in problems in the brake system. The level of the brake fluid is monitored electronically
page 32, “Brake system
”.
WARNING
Only apply the brakes for the purpose of
drying and cleaning the brake discs
if the traffic conditions permit this. Do not place any other road users in jeop-ardy.
When retrospectively mounting a front spoiler, solid wheel hubs etc. one
must ensure that the air supply to the
front wheel brakes is not reduced other-
wise the braking system could run too hot.
Allow for the fact that new brake pads
do not achieve their full braking effi-
ciency until approximately
200 kilometres. New brake pads must be first “run
in” before they develop their optimal friction force. You can, however, compen- sate for this slightly reduced braking force by increasing the pressure on the brake pedal. This guideline also applie
s to any new brake pads installed at a
future date.
Caution
Never allow the brakes to rub by applying sl
ight pressure if you do not wish to brake
the vehicle. This causes the br
akes to overheat and can also result in a longer braking
distance and excessive wear.
Before negotiating a steep downhill sectio
n, please reduce your speed and shift
down into the next lower gear (manual gear
box) or select a lower driving stage (auto-
matic gearbox). This enables
you to make full use of the braking power of the vehicle
and reduces the strain on the brakes. Any ad
ditional braking should be done intermit-
tently, not continuously.
Note
The brake light flashes automatically in case
of an emergency braking at speeds greater
than 60 km/h or with the intervention of th
e ABS, which lasts longer than 1.5 seconds.
After the speed was reduced below 10 km/h or the vehicle was stopped, the brake light stops flashing and the hazard warning light system switches on. The hazard warning light system is switched off automatically
after accelerating
or driving off again.
Brake boosterThe brake booster boosts the pressure whic
h you generate with the brake pedal. The
necessary pressure is only genera
ted when the engine is running.
WARNING
Never switch off the engine befo
re the vehicle is stationary.
The brake booster only operates when the engine is running. Greater phys-
ical effort for braking is required when en
gine is switched off.
Because if you do
not stop as normal, this can cause an accident and severe injuries.Antilock brake system (ABS)ABS prevents the wheels locking when braking.General The ABS contributes significan
tly to enhancing the active
safety of your vehicle.
Compared to a vehicle not fitted with the ABS brake system, you are able to retain optimal steering ability even during a full br
ake application on a slippery road surface
because the wheels do not lock up. You must not expect, however, that the braking distance will be shorter under all circumstances as a result of the ABS. The
braking distance for example on gravel and
fresh snow, when you should anyway be driv
ing slowly and cautiously, will be longer.
Operating principle As soon as the vehicle speed has increased to about 20 km/hour an automatic test procedure is conducted during which you wi
ll be able to hear a pumping noise for
about 1 second. The brake pressure will be reduced on a wheel which is rotating at a speed which is too low for the speed of the vehicle and tending
to lock. This control
cycle is noticeable
from a
pulsating movement of the brake pedal
which is accomp
anied by noises.
This is consciously intended to provide the driver with the information that the wheels are tending to lock (ABS control range). You must always keep the brake pedal depressed to enable the ABS to optimally control the brake application in this braking range. Never interrupt the application of the brakes!
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141
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
WARNING
The ABS can also not overcome the physical
limits of your vehicle. Please do
not forget this, particularly when driving on icy or wet road surfaces. If the ABS is operating within the control range,
adapt your speed immediately to the
conditions of the road surface and the traffic situation. The increased safety offered by the ABS must not tempt you to take greater risks than otherwise - risk of an accident!
The normal braking system is
still fully functional if there is an ABS fault.
Visit a specialist garage immediately and
adjust your style of driving according
to the damage to the ABS as you will no
t know how great the damage is and the
limitation it is placing on the braking efficiency.
Note
A warning light comes on if a fault occurs in the ABS system
page 32.
Changes to vehicle (e.g. on engine, on th
e brakes, on chassis or another combina-
tion of tyres and wheels) can in
fluence the function of the ABS
page 184, “Accesso-
ries, changes and replacement of parts”.Brake Assist*During a severe brake application (e.g. if a hazard exists), the Brake Assist increases the braking force and thus makes it possible to
rapidly produce the pressure required in
the brake system. The majority of drivers do apply the brakes
in good time in dangerous situations, but
do not depress the brake pedal with sufficient pressure. Consequently, it is not possible for the vehicle to achieve its maximum deceleration and the vehicle covers a greater distance than necessary. The Brake Assist is activated by the very quick operation of the brake pedal. In such cases, a much greater braking pressure exists
than during a normal
brake application.
This makes it possible, even with a relative
ly low resistance of the brake pedal, to
produce an adequate pressure in the brake system in the shortest possible time, which is required for maximum deceleration of th
e vehicle. You must apply the brake pedal
firmly and hold it in this position in order to achieve the shortest possible braking distance.
The Brake Assist is able to help you achi
eve a shorter braking distance in emergency
situations by rapidly producing the pressure required in the brake system. It fully exploits the attributes of the ABS. After you release the brake pedal, the function of the Brake Assist is automatically switched off
and the brakes operate in the normal way.
The Brake Assist is part of the ESP system. If
a fault occurs in the ESP, the Brake Assist
function is also not available.
Further information on the ESP
page 137.
WARNING
The Brake Assist is also not able to overcome the physical limits of your
vehicle in terms of the braking distance required.
Adapt your speed to the conditions of the road surface and to the traffic situ-
ation.
The increased safety offered by the Brake Assist must not tempt you to take
a greater safety risk than otherwise.Uphill Start Assist*The uphill start assist makes it easier to start off on steep hills. The system assists a start off by holding the brake pressure produced
by the brake pedal actuation for approx. 2
seconds after releasing the brake pedal. The driver can therefore move his foot from the brake pedal to the accelerator pedal and
start off on the slope, without having to
actuate the handbrake. The brake pressure drops gradually the more you operate the accelerator pedal. If the vehicle does not start
off within 2 seconds, it starts to roll back.
The uphill start assist is active as of a 3% slope, if the driver door is closed. It is always active on slopes when in forward or reverse start off. When driving downhill, it is inactive.Electrohydraulic power steeringThe power steering enables you to steer the vehicle with less physical force. The steering characteristics can be changed by a specialist garage.
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Intelligent Technology
142
You will place great stresses on the power steering system if the steering is turned to full lock when the vehicle is stationary. Turn
ing the steering to full lock in such a situa-
tion will be accompanied by noises. It is still possible to fully steer the vehicle if the power steering fails or if the engine is not running (vehicle being towed in). The only
difference is that gr
eater physical effort
is required. It is possible that the hydraulic pump of
the power steering will not run due to the low
vehicle network voltage if the battery has gone flat and the engine must started with the help off jump leads. This condition will
be indicated by lighti
ng up of the warning
light. The power steering operates again if the ba
ttery is charged to a specific range when
engine is running. It also op
erates again, if the engine
can be started with its own
battery. If there is a fault in the power steering, the warning light lights up in the instrument cluster
page 26.
Caution
Do not leave the steering at full lock fo
r more than 15 seconds when the engine is
running - risk of damagi
ng the power steering!
Note
Have the steering inspected as soon as possible by a specialist garage if there is a leak or fault in the system.
Tyre pressure monitoring system*The tyre pressure monitoring system compares with the aid of the ABS sensors the speed and also the rolling circumference of the individual wheels. If the tyre inflation pressure is significantly changed and thus the rolling circumference of a wheel, the warning light
lights up in the instrument cluster
page 31. The tyre pressure moni-
toring system functions late or too sensitively if:
the structure of the tyre is damaged,
the vehicle is loaded to one side or with a load on the roof,
the wheels of an axle are loaded heavily (e.g. when towing a trailer or when driving
uphill or downhill),
the vehicle is operated in unfavourable wi
nter conditions or
on an unfirm ground,
snow chains or emergency wheel* are mounted,
the driver has a sporty style of driving (with sharp acceleration and high speed
when cornering). Basic setting of the system After changing the tyre inflation pressures
or after changing one or several wheels, a
basic setting of the system mu
st be carried
out as follows.
Inflate all tyres to the specified inflation pressure
page 178.
Switch on the ignition.
Press button
fig. 131
for more than 2 seconds. While pressing the button,
the warning light
lights up. At the same time the basic values are stored, which is
confirmed with an acoustic sound and then the warning light
goes out.
Fig. 131 Button for setting the tyre inflation pressure control value
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