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194
•
when driving with snow chains
•
when driving in deep snow or on a loose surface
•
when it is necessary to rock a ca
r free when it has become stuck.
then you should switch on the ESP 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 surface and the traffic situation.
This particularly applies when driving on slippery and wet roads. The increased safety offered must not tempt you to take greater risks than other- wise - risk of an accident!
Note
•
All four wheels must be fitted with the same tyres in order to achieve problem-
free operation of the ESP. Differing rolling
circumferences of the tyres can lead to an
undesirable reduction in the engine output.•
Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign-
ment of tyres and wheels) can influence the function of the ESP
⇒page 241,
“Accessories, changes and replacement of parts”.Electronic Differential Lock (EDL)* The electronic differential lock pr
events an individual wheel from
slipping.Models fitted with ESP are equipped with electronic differential lock (EDL). General The EDL makes it much easier, and sometimes at all possible, to start off, accelerate and climb a steep hill when the conditio
ns of the road surface are unfavourable.
Operating principle The EDL is activated automatically, that is
without any action on the part of the
driver. It monitors the speeds of the driven wheels with the aid of the ABS sensors. Should only
one
drive wheel begin spinning on a slippery surface there will be an
appreciable difference in the speed of the driven wheels. The EDL function brakes the slipping wheel and the differential transmits a greater driving force to the other driven wheel. This control proces
s is also accompanied by noises.
Overheating of the brakes The EDL switches off
automatically if unusually severe
stresses exist in order to
avoid excessive heat generation in the
disc brake on the wheel which is being
braked. The vehicle can continue to be driv
en and has the same characteristics as a
vehicle not fitted with EDL. The EDL switches on again
automatically as soon as the brake has cooled down.
WARNING
•
Depress the accelerator carefully when accelerating on uniformly slip-
pery road surfaces, such as ice and sn
ow. The driven wheels might still spin
despite the EDL and affect the stability
of the vehicle - risk of an accident!
•
You should always adapt your style of driving to the condition of road
surface and to the traffic situation even
when your vehicle is fitted with EDL.
The increased safety offered must not tempt you to take greater risks than otherwise - risk of an accident!
Note
•
If the ABS or ESP warning light comes on,
this may also indicate a fault in the
EDL. Please have the car inspected as s
oon as possible by a specialist garage.
•
Changes to vehicle (e.g. on engine, on
the brakes, on chassis or other assign-
ment of tyres and wheels) can in
fluence the function of the EDL
⇒page 241,
“Accessories, changes and
replacement of parts”.
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Traction control system (TCS) The traction control system prevents
the driven wheels from spinning
when accelerating.General The TCS makes it much easier, and sometimes at all possible, to start off, accelerate and climb a steep hill when the conditio
ns of the road surface are unfavourable.
Operating principle The TCS switches on automatically when th
e engine is started and then conducts a
self-test. The system monitors the speeds of the driven wheels with the aid of the ABS sensors. If the wheels are spinning, the force transmitted to the road surface is automatically adapted by redu
cing the engine speed. Th
is occurs at all speeds.
The TCS operates in combination with the ABS
⇒page 197. The TCS will not func-
tion if a fault exists in the ABS system. The TCS warning light lights up in the instrument cluster when there is a fault on the TCS
⇒page 38.
Switching off You can switch the TCS off and on again
as you wish by pressing the button
⇒ fig. 191
. The TCS warning light lights up in the instrument cluster when the TCS is
switched off
⇒page 38.
The TCS should normally always be switched on. It may be good practice in certain exceptional cases, such as when you wish
to have wheel slip, to switch off the
system. Examples:•
when driving with snow chains
•
when driving in deep snow or on a loose surface
•
when it is necessary to rock a car free when it has become stuck.
then you should switch on the TCS again.
WARNING
You should always adjust your style of driving to the conditions of the road surface and the traffic situation. The increased safety offered must not tempt you to take greater risks than otherwise - risk of an accident!
Note
•
All four wheels must be fitted with the same tyres in order to achieve problem-
free operation of the TCS. Differing rolling circumferences of the tyres can lead to an undesirable reduction in the engine output.•
Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign-
ment of tyres and wheels) can in
fluence the function of the TCS
⇒page 241,
“Accessories, changes and replacement of parts”.Active driver-steering recommendation (DSR)*Vehicles with ESP are equi
pped with active driver-steering recommendation (DSR).
This function indicates to the driver in critical situations a steering recommendation in order to stabilise the vehicle. The active driver-steering recommendation is acti- vated, for example, on the right and left
vehicle side when
braking sharply on
different road surfaces.
Fig. 191 TCS switch
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196
WARNING
Even with this function the vehicle ca
nnot steer itself! The
driver is further-
more responsible for the steering of the vehicle!BrakesWhat has a negative effect on braking efficiency?Wear-and-tear Wear-and-tear to the brake pads is greatly dependent on the operating conditions of the vehicle and your style of driving. Particularly if you drive a great deal in towns and over short distances or if you adopt a
sporty style of driving, it may be neces-
sary to have the thickness of the brake
pads inspected at a specialist garage
between the service inspections. Wet roads or road salt There may be a certain delay before the br
akes take full effect under certain condi-
tions such as when driving through water,
during heavy rain
showers or after the
vehicle has been washed in
an automatic vehicle wash, since the brake discs and
brake pads may be moist or even have a
coating of ice on them in winter. You
should dry the brakes as soon as possib
le by applying and releasing the brakes
several times. There also may be a certain delay before the
full braking efficiency is available when
driving on roads which have been treated wi
th road salt if yo
u have not used the
brakes for some considerable time beforeha
nd. The layer of salt on the brake discs
and brake pads must first be rubb
ed off when you apply the brakes.
Corrosion Corrosion on the brake discs and dirt on th
e bake pads occur if
the vehicle has been
parked for a long period and if you do
not make much use of the braking system.
We recommend cleaning the brake discs by
firmly applying the brakes at a fairly
high speed if you do not make much use of the braking system or if surface corro- sion is present
⇒
.
Faults in the brake surface If you notice that the braking distance
has suddenly become longer and that the
brake pedal can be depressed further, it is
possible that a brake circuit of the dual-
circuit brake system has failed. Drive, in such cases, to the nearest specialist garage without delay in order to have the problem rectified. Drive at a reduced speed while on your way to the dealer and adapt your style of driving to the higher brake pedal pressure required. 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 41, “Brake system
”.
WARNING
•
Only apply the brakes for the purpos
e of drying and cleaning the brake
discs if the traffic conditions permit this. Do not place any other road users in jeopardy.•
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 otherwise the braking sy
stem could run too hot.
•
Allow for the fact that new brake pads
do not achieve th
eir full braking
efficiency until approximately 200 kilo
metres. New brake pads must be first
“run in” before they develop their optimal friction force. You can, however, compensate for this slightly reduced
braking force by increasing the pres-
sure on the brake pedal. This guidelin
e also applies to any new brake pads
installed at a future date.
Caution
•
Never allow the brakes to ru
b by applying slig
ht pressure if you do not wish to
brake the vehicle. This causes the brakes to overheat and can also result in a longer braking distance and excessive wear.•
Before negotiating a steep downhill sect
ion, please reduce your speed, shift
down into the next lower gear (manual ge
arbox) or select a lower driving stage
(automatic gearbox). This enables you to make full use of the braking power of the
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
vehicle and reduces the strain on the brakes
. Any additional braking should be done
intermittently, no
t continuously.
Note
The brake light flashes automa
tically in case of an em
ergency braking at speeds
g re a t e r t h a n 6 0 k m /h o r w i t h t he i n t e r v e n t i o n o f th e A BS , w h i ch l a s t s l o n g e r th a n 1 .5 seconds. After the speed was reduced belo
w 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 which you generate with the brake pedal. The necessary pressure is only gene
rated when the engine is running.
WARNING
•
Never switch off the engine before the vehicle is stationary.
•
The brake booster only operates when the engine is running. Greater
physical effort for braking is required
when engine 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 car not fitted with the ABS brake system, you are able to retain optimal steering ability even during a fu
ll brake application on a slippery road
surface because the wheels do not lock up. You must not expect, however, that the br
aking distance will be shorter under all
circumstances as a result of the ABS. Th
e braking distance for example on gravel
and fresh snow, when you should anyway be driving slowly and cautiously, will be longer. Operating principle 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 tend
ing to lock. This control cycle is notice-
able from a
pulsating movement of the brake pedal
which is accompanied 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 optima
lly control the brake application in this
braking range. Never interrupt the application of the brakes!
WARNING
•
The ABS can also not overcome the physic
al limits of your vehicle. Please
do not forget this, particularly when driv
ing on icy or wet road surfaces. If the
ABS is operating within the control ra
nge, 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 as quickly as po
ssible and adjust yo
ur style of driving
to take account of the ABS fault in the meantime since you will not know how great the damage is.
Note
•
A warning light comes on if a fault occurs in the ABS system
⇒page 39.
•
Changes to vehicle (e.g. on engine, on the brakes, on chassis or other assign-
ment of tyres and wheels) can in
fluence the function of the ABS
⇒page 241,
“Accessories, changes and replacement of parts”.
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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 su
fficient pressure. Consequently, it is not
possible for the car to achieve its maxi
mum deceleration and the car 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 ex
ists than during a normal brake applica-
tion. This makes it possible, even with a relatively 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 the car. 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 achieve 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 193.
WARNING
•
The Brake Assist is also not able to overcome the physical limits of your
car in terms of the braking distance required.•
Adapt your speed to the conditions of the road surface and to the traffic
situation.•
The increased safety offered by the Brake Assist must not tempt you to
take a greater safety risk than otherwise.
Uphill-Start
off-Assist*
The uphill-start off-assist makes it much easier to start off on steep hills. The system assists a start off by holding the brake pr
essure produced by the brake pedal actu-
ation for approx. 2 seconds after releasing the brake pedal. The driver can therefore move his foot from the brake pedal to th
e accelerator pedal and start off on the
slope, without having to actuate the hand
brake. 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 off-assist is active in the ev
ent of a 5% slope, if the vehicle door is
closed. It is alwa
ys active on slopes when in forward or reverse start off. When
driving downhill, it is inactive.Electromechanical power steeringThe power steering enables you to steer
the vehicle with le
ss physical force.
With the electromechanical power steering, the steering assist is automatically adapted to the speed and to the steering angle. 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 greater physical
effort is required. If there is a fault in the power steering, the warning light
or lights up in the
instrument cluster
⇒page 36.
WARNING
Contact your specialist
garage if the power steering is defective.
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Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Tyre inflation pressu
re-control system*
The tyre inflation pressure-control system compares with the aid of the ABS sensors the speed and also the rolling circumference
of the individual wheels. If the rolling
circumference of a wheel is changed, the warning light°
lights up in the instru-
ment cluster
⇒page 39. The rolling circumference of the tyre can change if:
•
the tyre inflation pressure is too low,
•
the structure of the tyre is damaged,
•
the vehicle is loaded on one side,
•
the wheels of an axle are loaded heavily (e.g. when towing a trailer or when
driving uphill or downhill),•
snow chains are mounted,
•
the temporary spare wheel is mounted,
•
one wheel per axle was changed.
Basic setting of tyre inflation pressure-control system After changing the tyre inflation pressures or after changing one or several wheels, a basic setting of the system must be carried out as follows.•
Inflate all tyres to the specified inflation pressure
⇒page 235.
•
Switch on the ignition.
•
Press button
⇒fig. 192
for more than 2 seconds. While pressing the
button, the warning light
lights up. At the same time the memory of the system
is erased and the new calibration is star
ted, which is confirmed with an audible
signal and then the warning light
goes out.
•
If the warning light
does not go out after the basic setting, there is a fault in
the system. Have the vehicle inspected by your nearest specialist garage. Warning light
lights up
If the tyre inflation pressure of at least on
e wheel is insufficiently inflated in compar-
ison to the stored basic value, the warning light
⇒
lights up.
Warning light
flashes
If the warning light flashes, there is a system fault. Have the vehicle inspected by your nearest specialist garage.
WARNING
•
When the warning light
lights up, immediately reduce the speed and
avoid sudden steering and brake mano
euvres. Please stop the vehicle
without delay at the nearest possible stop and inspect the tyres and their inflation pressures.•
The driver is responsible for the correc
t tyre inflation pressures. For this
reason, the tyre inflation pressures must be checked regularly.•
Under certain circumstances (e.g. sporty style of driving, wintry or
unpaved roads) the warning light
can be delayed or does not light up at
all.•
The tyre inflation pressure-control system does not take away the
responsability from the driver for the correct tyre inflation pressure.
Note
The tyre inflation pressure-control system:•
does not replace the regular tyre inflatio
n pressure control, because the system
cannot detect an even pressure loss,•
cannot warn in case of very rapid tyre inflation pressure loss, e.g. in case of
sudden tyre damage. In this
case carefully bring the vehi
cle to a standstill without
sudden steering movements and without sharp braking.
Fig. 192 Button for setting the tyre inflation pressure control value
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200
Diesel particle filter* (diesel engine)In the diesel particle filter the resulting soot particles are collected and burnt during the combustion of diesel fuel.Code
7GG
, 7MB
or
7MG
on the vehicle data sticker, see
⇒
fig. 193
, indi-
cates that your vehicle is equipped with
a diesel particle filter. The vehicle
data sticker is located on the floor of the luggage compartment and is also stated in the Service schedule.The diesel particle filter filters the soot particles completely from the exhaust. The soot is collected in the diesel particle filter and burnt regularly. To assist this proce- dure, we recommend not to drive
regularly over short distances.
If the diesel particle filter is clogged or there is a fault, it is indicated by the warning light
.WARNING
•
The diesel particle filter
achieves very high te
mperatures. Therefore do
not park at points where the hot filter comes into direct contact with dry grass or other combustible materials - risk of fire!
•
Never use additional underbody protection or corrosion-protection
agents for the exhaust pipes, catalytic
converters, diesel particle filter or
heat shields. When the engine reaches its operating temperature, these substances might ignite - risk of fire.
Note
When using diesel fuel with high sulphur content the life of the diesel particle filter is clearly reduced. A specialist garage wi
ll be able to tell you which countries use
only diesel fuel with high sulphur content.
Fig. 193 Vehicle data sticker
WARNING (continued)
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201
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Driving and the EnvironmentA new engineThe engine has to be run in during the first 1 500 kilometres.Up to 1 000 kilometres – Do not drive faster than 3/4 of the mamimum speed of the gear in use,
that is 3/4 of the maximum permissible engine speed.
– Do not use full throttle.– Avoid high engine revolutions. – Do not tow a trailer. From 1 000 up to 1 500 kilometres – Increase the power output of the engine
gradually
up to the full
speed of the gear engaged, that
is up to the maximum permissible
engine revolutions.
During the first operating hours the engine
has higher internal
friction than later
until all of the moving parts have harmonized. The driving style which you adopt during the first approx.1 500 kilometres
plays a decisive part in the success of
running in your car. You should not drive at unnecessarily
high engine revolutions
even after the
running-in period is
complete. The maximum permissib
le engine spee
d is marked
by the beginning of the red zone on the scale of the revolutions counter. Shift up into the next higher gear on a vehicle
fitted with manual gearbox before the red
zone is reached.
Extremely
high engine revolutions are automatically governed, by
the way. For a vehicle fitted with a manual gearbox
the converse situation also applies: Do
not drive at engine revolutions which are
too low
. Shift down as soon as the engine
is no longer running smoothly.
Caution
All the speed and engine revolution figure
s apply only when the engine is at its
normal operating temperature. Never rev up
an engine which is cold, neither when
the vehicle is stationary nor when driving in individual gears.
For the sake of the environment
Not driving at unnecessarily high engine revolutions and shifting to a higher gear as early as possible are ways to minimise fuel consumption and operating noise levels and protects the environment.New tyresNew tyres have to be “run in” since they do
not offer optimal grip at first. You should
take account of this fact for the first 500 kilometres and drive particularly carefully.New brake padsAllow for the fact that new brake pads do
not achieve their full braking efficiency
until approximately 200 kilometres. New brake pads must be first “run in” before they develop their optimal friction force.
You can, however, compensate for this
slightly reduced braking force by increasing the pressure on the brake pedal. This guideline also applies to any new
brake pads installed at a future date.
During the running-in period, you should
avoid excessive stresses on the brakes.
This includes, for example, violent braking,
particularly from very high speeds, and
also when crossing mountain passes.
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