19
Seat 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. 7 Vehicle about to
hit a wall: the occupants
are not wearing seat
belts
Fig. 8 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. 7, 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 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. 8.
Even at speeds of 30 km/h (20 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.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
21
Seat belts
Seat belt protection
Passengers not wearing seat belts risk severe injuries in the
event of an accident.
Fig. 11 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.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
29
Airbag system
WARNING (Continued)
● To reduce the risk of injury from an inflating airbag, always wear the
seat belt properly ⇒ page 18.
● 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 44. 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 deactivate the air-
bag, the vehicle must be taken to a Technical Service.
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.
● 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 44, Deactivating
airbags.
– 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.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
65
Cockpit
Warning and indicator lamps General description
The warning and indicator lamps indicate a number of dif-
ferent functions and possible faults.
Fig. 45 Instrument panel with warning and indicator lamps
Exhaust emission control system⇒ page 66
Airbag system⇒ page 66
Tyre pressure too low⇒ page 67
Cruise speed (Cruise control)⇒ page 67
Trailer turn signals⇒ page 67
Anti-lock brake system (ABS)⇒ page 68
Seat belt warning⇒ page 68
If it stays lit: ASR switched off⇒ page 69
⇒ page 69
⇒ page 165
Left turn signals⇒ page 69
If flashing: the Electronic Stability Control
(ESC) is working or the ASR is working
If the following remain lit: ESC or ASR
faulty⇒ page 69
⇒ page 69
⇒ page 165
Alternator⇒ page 70
Main beam headlights⇒ page 70
Handbrake on⇒ page 70
⇒ page 77
Engine management (alternative to )⇒ page 70
Glow plug system (alternative to )⇒ page 70
Fault in brake system⇒ page 71
Right turn signals⇒ page 69
Safety FirstOperating instructionsPractical TipsTechnical Specifications
68Cockpit
Where a turn signal bulb does not work, either on the trailer or on the tow-
ing vehicle, the turn signal bulb will not flash.
Anti-lock brake system (ABS)
The warning lamp monitors the ABS and the integrated elec-
tronic differential lock (EDL).
The control lamp lights up for a few seconds when the ignition is switch-
ed on and while the engine is being started. The lamp goes out again after
the system has run through an automatic test sequence.
There is a fault in the ABS if:
● The warning lamp does not light up when the ignition is switched on
● The control lamp does not go out again after a few seconds.
● The control lamp lights up when the vehicle is moving.
The vehicle can still brake in the normal way (except that the ABS control
function is out of action). Please take the vehicle to a specialised workshop
as soon as possible. For further information on the ABS, see ⇒ page 189.
If a malfunction should occur in the ABS, the ESC warning lamp will also
light up.
Entire brake system fault
If the ABS warning lamp lights up together with the brake warning lamp
⇒ page 71 (with the handbrake released), this indicates not only a
fault in the ABS function, but probably also a malfunction in the main brake
system ⇒
.
The symbol will light up on the instrument panel if there if a fault in the
brake system. Please refer to ⇒ page 78. Electronic differential lock (EDL) fault
The EDL works in conjunction with the ABS. The ABS control lamp will light
up to indicate an EDL fault. Please take the vehicle to a specialised work-
shop as soon as possible. For further information on the EDL, see
⇒ page 190.
WARNING
● Before opening the bonnet and checking the brake fluid level, ob-
serve the warning information in ⇒ page 227, Work in the engine com-
partment.
● If the brake warning lamp should light up together with the ABS
warning lamp , stop the vehicle immediately and check the brake fluid
level in the reservoir. If the fluid level has dropped below the "MIN" mark
you must not drive on, as there is a risk of accident. Obtain technical as-
sistance.
● If the brake fluid level is correct, the fault in the brake system may
have been caused by a fault in the ABS control function. As a result, the
rear wheels can lock relatively easily when braking. Under certain cir-
cumstances, the rear of the vehicle could suddenly sway from side to
side, with the subsequent danger of skidding. Drive carefully to the near-
est specialised workshop and have the fault repaired.
Seat belt warning lamp*
The warning lamp acts as a reminder to the driver to fasten
the seat belt. After switching on the ignition, the warning lamp will remain lit until the
driver and front passenger (if applicable) have fastened their seat belts.
When the vehicle has reached a certain speed, you will also hear a warning
signal and the warning light will flash.
For further information on the seat belts, see ⇒ page 23.
69
Cockpit
Turn signals and hazard warning lights
Depending on which turn signal is operated, either the left or right turn
signal lamp flashes. Both turn signal lamps will flash when the hazard warn-
ing lights are switched on.
If a turn signal fails, the indicator lamp will start flashing twice as fast as
normal.
This does not apply when towing a trailer. Where a turn signal bulb does not
work, either on the trailer or on the towing vehicle, the turn signal bulb will
not flash. For further information on the turn signals, see ⇒ page 122.
Electronic Stability Control (ESC)* /
There are two control lamps for the electronic stability con-
trol. The lamp provides information concerning the func-
tion and the provides information on the disconnection
status
Both lamps come on together when the ignition is switched on and should
go out after approx. 2 seconds, which is how long the function check lasts.
This programme includes the ABS, EDL and ASR. This also includes the
brake assistance system (BAS), automatic cleaning of the brake discs and
the trailer stability programme (TSP).
The warning lamp has the following functions:
● It flashes whilst driving when the ASR/ESC is activated.
● It will light up continuously if there is a fault in the ESC.
● As the ESC operates in conjunction with the ABS, it will also light up if a
fault should occur in the ABS. If the ESC control lamp
lights up and stays on after the engine is started,
this may mean that the control system has temporarily switched off the ESC.
In this case the ESC can be reactivated by switching the ignition off and
then on again. If the control lamp goes out, this means the system is fully
functional.
The lamp provides information about the disconnection status of the
system:
● It stays lit when the ASR is disconnected when pressing the switch.
Traction control system (ASR)* /
The traction control system prevents the driven wheels from
spinning when the vehicle is accelerating
There are two warning lamps for the traction control system: and . Both
lamps come on together when the ignition is switched on and should go out
after approx. 2 seconds, which is how long the function check lasts.
The lamp has the following function:
● It flashes when the ASR is working if the vehicle is moving.
If the system is deactivated or if it has any fault, the warning lamp will re-
main lit. The warning lamp will also light up if a fault should occur in the
ABS because the ASR operates in conjunction with the ABS. For further in-
formation, see ⇒ page 188.
The lamp provides information about the disconnection status of the
system:
● It stays lit when the ASR is disconnected when pressing the ASR OFF
switch.
By pressing it again, the ASR function is reactivated and the warning lamp
switched off.
Safety FirstOperating instructionsPractical TipsTechnical Specifications
70Cockpit
Alternator
The warning lamp signals a fault in the alternator or in the
vehicle's electrical system.
The control lamp lights up when the ignition is switched on. It should
switch off after the engine has started.
The alternator is disconnected at very low temperatures and when the en-
gine is cold in order to facilitate starting.
Depending on the external temperature, the warning lamp might remain
on for up to 5 seconds after the engine has been started. This does not
therefore indicate a fault.
If the warning lamp lights up when you are driving, you can normally
continue as far as the nearest specialised workshop. However, given that
the battery will be running down, any electrical consumption not absolutely
vital should be switched off.
CAUTION
If the coolant warning lamp in the instrument panel lights up as well as
the alternator waning lamp while driving ⇒ page 79, stop the vehicle im-
mediately and switch off the engine. In this case the coolant pump is no
longer working, and there is a risk of engine damage.
Main beam headlights
The indicator lamp lights up when the main beams are on or when the
headlight flasher is operated.
For further information on the main beam headlights, see ⇒ page 122.Handbrake
This lamp lights up when the handbrake is applied.
If you drive faster than 5 km/h (4 mph) with the handbrake on, the following
message will appear on the instrument panel display 1)
: HANDBRAKE ON. You
will also hear an acoustic warning signal ⇒ page 77.
Engine management
This warning lamp monitors the engine management sys-
tem for petrol engines.
The control lamp (Electronic Power Control) lights up while the function
is being checked.
Note
If the warning lamp lights up while the vehicle is moving, this indicates a
fault in the engine management system. The vehicle must be taken immedi-
ately to a specialised workshop to have the engine serviced.
Glow plug system
The control lamp lights up while the glow plugs are preheat-
ing the diesel engine. The control lamp lights up while the glow plugs are preheating. When
the indicator lamp goes out the engine should be started straight away.
1)
Depending on the version of the model.
71
Cockpit
When the engine is warm, or at outside temperatures above +8 °C, the
warning lamp will only light up very briefly.
Note
● If the glow plug indicator lamp should start flashing while the vehicle is
moving, this indicates a fault in the engine management system. The en-
gine should be serviced without delay.
● If the indicator lamp fails to light up when the ignition is switched on,
this can mean that the glow plug system is defective. The engine should be
serviced.
Brake system
The warning lamp flashes when the handbrake is applied, or
if the brake fluid level is too low or if there is a fault in the
ABS system. If the control lamp flashes (and the handbrake is not applied), stop the
vehicle and check the brake fluid level ⇒
⇒ page 237.
If a failure should occur in the ABS, the ABS control lamp will light up
together with the brake control lamp ⇒
.
Handbrake on
The control lamp also lights up when the handbrake is applied. In addi-
tion to this, the handbrake warning ⇒ page 77 switches on after driving
for 3 seconds at a speed above 5 km/h.
WARNING
● Before opening the bonnet and checking the brake fluid level, ob-
serve the warning information in ⇒ page 227, Work in the engine com-
partment.
● If the brake warning lamp does not go out, or if it lights up when driv-
ing, the brake fluid level in the reservoir is too low and this may cause an
increased accident risk. Stop the vehicle and do not drive on. Obtain
technical assistance.
● If the brake warning lamp lights up together with the ABS warning
lamp, this can mean that there is a fault in the ABS control function. As a
result, the rear wheels can lock relatively easily when braking. Under cer-
tain circumstances, the rear of the vehicle could suddenly sway from side
to side, with the subsequent danger of skidding. Drive carefully to the
nearest specialised workshop and have the fault repaired.
Safety FirstOperating instructionsPractical TipsTechnical Specifications