22Seat belts
Why wear seat belts?
Physical principles of frontal collisions
In the event of a frontal collision, a large amount of kinetic
energy must be absorbed.
Fig. 6 Vehicle about to
hit a wall: the occupants
are not wearing seat
belts
Fig. 7 The vehicle hits
the wall: the occupants
are not wearing seat
belts
It is easy to explain how the laws of physics work in the case of a head-on
collision: When a vehicle starts moving ⇒ Fig. 6, a certain amount of energy
known as kinetic energy is produced in the vehicle and its occupants.
The amount of kinetic energy depends on the speed of the vehicle and the
weight of the vehicle and its passengers. The higher the speed and the
greater the weight, the more energy there is to be released in an accident.
The most significant factor, however, is the speed of the vehicle. If the
speed doubles from 25 km/h (15 mph) to 50 km/h (30 mph), for example,
the corresponding kinetic energy is multiplied by four.
Because the vehicle occupants in our example are not restrained by seat
belts, all of the occupants' kinetic energy has to be absorbed at the point of
impact ⇒ Fig. 7.
Even at speeds of 30 km/h (19 mph) to 50 km/h (30 mph), the forces acting
on bodies in a collision can easily exceed one tonne (1000 kg). At greater
speed these forces are even higher.
24Seat belts
Seat belt protection
Passengers not wearing seat belts risk severe injuries in the
event of an accident.
Fig. 10 A driver wearing
the seat belt properly is
secured by the belt in
sharp braking
Properly worn seat belts hold the vehicle occupants in the correct sitting po-
sitions and substantially reduce the kinetic energy in the event of an acci-
dent. Seat belts also help to prevent uncontrolled movements that could
lead to severe injuries. In addition, properly worn seat belts reduce the dan-
ger of being thrown from the vehicle.
Vehicle occupants wearing their seat belts correctly benefit greatly from the
ability of the belts to absorb kinetic energy. The front part of your vehicle
and other passive safety features (such as the airbag system) are also de-
signed to absorb the kinetic energy released in a collision. Taken together,
all these features reduce the releasing kinetic energy and consequently, the
risk of injury.
Our examples describe frontal collisions. Of course, properly worn seat belts
substantially reduce the risk of injury in all other types of accidents. This is
why it is so important to fasten seat belts before every trip, even when "just
driving around the corner". Ensure that your passengers wear their seat belts as well. Accident statistics
have shown that wearing seat belts is an effective means of substantially
reducing the risk of injury and improving the chances of survival in a seri-
ous accident. Furthermore, properly worn seat belts improve the protection
provided by airbags in the event of an accident. For this reason, wearing a
seat belt is required by law in most countries.
Although your vehicle is equipped with airbags, the seat belts must be fas-
tened and worn. The front airbags, for example, are only triggered in some
frontal accidents. The front airbags will not be triggered during minor frontal
collisions, minor side collisions, rear collisions, overturns or accidents in
which the airbag trigger threshold value in the control unit is not exceeded.
Therefore, you should always wear your seat belt and ensure that all vehicle
occupants have fastened their seat belts properly before you drive off!
Safety instructions on using seat belts
If seat belts are used correctly, they can considerably reduce
the risk of injury in an accident.
– Always wear the seat belt as described in this section.
– Ensure that the seat belts can be fastened at all times and are
not damaged.
32Airbag system
WARNING (Continued)
● To reduce the risk of injury from an inflating airbag, always wear the
seat belt properly ⇒ page 20.
● Always adjust the front seats properly.
The danger of fitting a child seat on the front passenger
seat
Rear-facing child seats must never be used on the front pas-
senger seat when the front passenger airbag is enabled. The front passenger front airbag is a serious risk for a child if it is activated.
The front passenger seat is life threatening to a child if he/she is transpor-
ted in a rear-facing child seat. Children up to 12 years old should always
travel on the rear seat.
If a rear-facing child seat is secured to the front passenger seat, an inflating
airbag can strike it with such force that it can cause critical or fatal injuries.
Therefore we strongly recommend you to transport children on the rear
seats. That is the safest place for children in the vehicle. Alternatively, the
front passenger airbag can be disabled with a key-operated switch
⇒ page 43. When transporting children, use a child seat suitable for the
age and size of each child ⇒ page 46.
For those vehicles that do not include a key lock switch to turn the airbag
off, a Technical Service must be consulted.
WARNING
● If a child seat is secured to the front passenger seat, the risk to the
child of sustaining critical or fatal injuries in the event of an accident in-
creases.
● Never secure a rear-facing child seat to the front passenger seat if the
front passenger airbag is enabled. The child can suffer critical or fatal in-
juries if the front passenger airbag is triggered.
● An inflating front passenger airbag can strike the rear-facing child
seat and project it with great force against the door, the roof or the back-
rest.
● For those vehicles that do not include a key lock switch to turn the
airbag off, a Technical Service must be consulted.
● If, under special circumstances, it is necessary to transport a child in
a rear-facing child seat on the front passenger seat, it is absolutely es-
sential that you observe the following safety measures:
–Deactivate the front passenger airbag ⇒ page 43.
– Child seats must be approved by the child seat manufacturer for
use on a front passenger seat with front or side airbag.
– Follow the installation instructions given by the child seat manu-
facturer and observe the safety instructions ⇒ page 46, Child safe-
ty.
– Before properly installing the child seat, push the front passenger
seat completely backwards so that the greatest possible distance to
the front passenger airbag is ensured.
– Ensure that no objects prevent the front passenger seat from being
pushed completely back.
– The backrest of the front passenger seat must be in an upright po-
sition.
69
Controls and displays
Control lamps
Summary
The control lamps indicate certain functions or faults accompanied by an
audible warning.
When the ignition is switched on some of the warning lamps light up for
several seconds for the purpose of the control systems of the vehicle. These
warning lamps must switch off several seconds after the ignition is switched
on.
Handbrake⇒ page 70
Brake system⇒ page 70
Fasten your seat belt⇒ page 70
Alternator⇒ page 71
Door open⇒ page 71
Engine oil (red or yellow colour)⇒ page 71
Coolant temperature/level (red or blue colour)⇒ page 72
Power steering⇒ page 72
Electronic stability control (ESC)⇒ page 72
Traction control system (ASR)⇒ page 73
Anti-lock brake system (ABS)⇒ page 73
Rear fog light⇒ page 73
Bulb fault⇒ page 74
Emission control system⇒ page 74
Glow plug system (diesel engines)⇒ page 74
Engine electronics control (petrol engines)⇒ page 74
Particulate filter (diesel engines)⇒ page 74
Fuel reserve⇒ page 75
Airbag system⇒ page 75
Tyre pressure⇒ page 76
Liquid level in the window washer system⇒ page 76
Turn signals (left/right)⇒ page 76
Fog lights⇒ page 76
Cruise speed⇒ page 77
Safety FirstOperating instructionsPractical TipsTechnical specifications
70Controls and displays
Selector lever lock⇒ page 77
Main beams⇒ page 77
WARNING
● Failure to observe control lamps and warning messages can result in
serious personal injuries or damage to your vehicle.
● The engine compartment is a dangerous area. Carrying out work in
the engine compartment, i.e. checking and filling service liquids, can
lead to injury, scalding, burns and fires. Therefore the corresponding
warnings must always be observed ⇒ page 182, Engine compartment.
Handbrake
If the warning lamp lights up, the handbrake is applied. Additionally,
driving the vehicle at speeds exceeding 6 km/h (4 mph) for at least 3 sec-
onds produces an audible warning.
The informative display indicates:
Release the handbrake!
Brake system
The warning lamp lights up if the brake fluid level falls too low or if there
is a fault in the ABS system.
The informative display indicates:
Brake fluid Instruction Manual! Stop the vehicle, switch off the engine and check the level of the brake fluid
⇒ page 189
WARNING
● If the vehicle has to be stopped for technical reasons, park it a safe
distance away from moving traffic, switch off the engine and turn on the
hazard warning lights ⇒ page 101.
● The following indications must be taken into account when opening
the engine compartment to check the brake fluid ⇒ page 182, Engine
compartment.
● If the warning lamp lights up together with the warning lamp
⇒ page 73, Anti-lock system (ABS) , , Stop the vehicle! Seek pro-
fessional help.
● A fault in the brake system or in the Anti-lock brake system (ABS) can
lead to longer braking distances – Risk of accident!
Fastening seat belts
After switching on the ignition, the warning lamp lights up to instruct the
driver or front passenger to fasten their seat belt. The warning lamp switch-
ed off when the driver or front passenger fastens their seat belt.
While driving at a speed in excess of 20 km/h (12 mph), and if the driver or
front passenger does not have their seat belt fastened an audible warning
is given and the control lamp lights up .
If the driver or front passenger does not fasten their seat belt during the fol-
lowing 90 seconds the audible warning switches off while the warning lamp
will remain up.
73
Controls and displays
The informative display indicates: Report No.: Stability control (ESC)
or Report No.: Traction control system (ASR)
Seek professional help.
Further information ⇒ page 144, Stability system (ESC).
Note
If the battery is disconnected and connected again, the yellow warning
lamp lights up when the ignition is switched on. This warning lamp must
switch off after covering a short distance.
Traction control system (ASR)
If the control lamp
flashes, the ASR is working.
If the warning lamp lights up on ignition the ASR system may have
switched off due to technical reasons. Turn off the ignition and turn it on
again. Upon switching on the ignition again, if the warning lamp has switch-
ed off, this means the ASR is functioning correctly again.
If the warning lamp, remains lit up there is a fault in the ASR.
The informative display indicates: Report No.: Traction control system (ASR)
Seek professional help.
Further information ⇒ page 145, Traction control system (ASR). Anti-lock system (ABS)
If the warning lamp, is lit up there is a fault in the ABS.
The informative display indicates: ABS fault
The brake system alone is operational in the vehicle, without ABS.
Seek professional help.
WARNING
● If the vehicle has to be stopped for technical reasons, park it a safe
distance away from moving traffic, switch off the engine and turn on the
hazard warning lights ⇒ page 101.
● If the warning lamp ⇒ page 70 lights up together with the warning
lamp , , Stop the vehicle! Seek professional help.
● A fault in the Anti-lock brake system (ABS) can lead to longer braking
distances – Risk of accident!
Rear fog light
The control lamp lights up when the rear fog light is switched on
⇒ page 99.
Safety FirstOperating instructionsPractical TipsTechnical specifications
143
Driving
● Vehicle modifications (e.g. to the engine, brakes, frame or a combina-
tion of wheels and tyres) could impair the brake assist systems
⇒ page 204, Accessories, modifications and spare parts.
● In the event of a fault in the ABS system, the ESC, ASR and EDL are
switched off automatically. A fault in the ABS is indicated by the
⇒ page 73 warning lamp.
Brakes
Wear
The rate of wear of the brake pads depends on the driving style and on the
way in which the vehicle is used. The brake pads will wear more quickly if
you use your vehicle frequently in urban traffic and short trips or drive in a
sporty style. Under these demanding conditions, visit your specialised serv-
ice, even before the scheduled service date, so that the thickness of the
brake pads can be measured.
Wet roads or road salt
If brakes are wet or frozen, or if you are driving on roads which have been
gritted with salt, braking power may set in later than normal. Dry the brakes
as soon as possible by braking repeatedly.
Corrosion
Long periods of inactivity and little use can lead to rust on the brake discs
and dirt on the brake pads. Where the brake system is subjected to light
stress or in the case of corrosion, clean the brake discs by braking fully sev-
eral times at a high speed.
Brake system fault
If you notice that the braking distance suddenly increases and the brake
pedal can be pressed down more fully, there may be a fault in the brake sys-
tem. Visit a specialised service immediately and adjust your driving style to
the extent of the damage and to limit the effect of the brakes. Low brake fluid level
Insufficient brake fluid could cause faults in the brake system. The brake flu-
id level is controlled electronically
⇒ page 70, Brake system .
Brake servo
The brake servo supplements the pressure you exert on the brake pedal.
The brake servo only works when the engine is running.
Handbrake
Fig. 102 Centre console:
handbrake
Applying the handbrake
– Pull the handbrake lever up all the way.
Releasing the handbrake
– Pull the handbrake lever up slightly and press the unlock button
at the same time ⇒ Fig. 102.
– Keep the button pressed down and push the lever all the way
down.
Safety FirstOperating instructionsPractical TipsTechnical specifications
144Driving
The warning lamp lights up when the handbrake is applied with the ignition
on .
Stability system (ESC)
Fig. 103 ESC system:
ASR switch
The ESC system increases control of the vehicle in emergency situations,
e.g. during a sudden change in direction. Depending on the driving condi-
tions, it reduces the risk of skidding and increases driving stability.
The system uses the steering wheel angle and road speed to calculate the
changes of direction desired by the driver, and constantly compares them
with the actual behaviour of the vehicle. When irregularities occur, for exam-
ple, if the vehicle begins to skid, the ESC brakes the appropriate wheel au-
tomatically.
The warning lamp in the general instrument panel starts flashing when
the system is working.
The stability (ESC) system includes the following systems:
● Anti-lock brake system (ABS)
● Traction control system (ASR)
● Electronic differential lock (EDL) ●
Brake assist system (HBA)
● Hill hold control (HHC)
The ESC system cannot be switched on. The
⇒ Fig. 103 button can only
be used to switch off the ASR system. The warning lamp lights up on the
general instrument panel if the ASR system is switched off.
The ASR should be switched on at all times. Only under certain circumstan-
ces should the system be switched off, e.g.
● Driving with chains
● Driving in deep snow or on very soft surfaces
● During the “swinging movement” required to remove a stuck vehicle
Switch the ASR back on as soon as possible.
Brake assist system (HBA)*
The HBA system is activated when you press down on the brake pedal sud-
denly. It increases braking power, helping to reduce braking distances. To
reduce the braking distance as much as possible, keep the brake pedal
pressed down firmly until the vehicle comes to a standstill.
With the help of this system, the ABS is activated more quickly and more
efficiently.
The brake assist function is deactivated automatically when the brake pedal
is released.
Hill hold control (HHC)*
The HHC system makes it easier to start the vehicle on hills. The system
maintains the brake pressure created by pressing down on the brake pedal
for 2 seconds after it has been released. Your foot can be removed from the
brake pedal and you can use the accelerator pedal and move away on a hill
without having to use the handbrake. The brake pressure drops as the ac-
celerator pedal is pressed. If the vehicle is not started then it will start to
move backwards after two seconds.