Intelligent technology
172Anti-lock brake system and traction control
M-ABS (ABS and TCS)Anti-lock brake system (ABS)
The anti-lock brake system prevents the wheels locking
during braking.The anti-lock brake system (ABS) is an important part of the vehicle's active
safety system.
How the ABS works
If one of the wheels is turns too slowly in relation to the road speed, and is
close to locking, the system will reduce the braking pressure for this wheel.
The driver is made aware of this control process by a pulsating of the brake
pedal and audible noise. This is a deliberate warning to the driver that one or
more of the wheels is tending to lock and the ABS control function has inter-
vened. In this situation it is important to keep the brake pedal fully depressed
so the ABS can regulate the brake application. Do not “pump”.
If you brake hard on a slippery road surface, the best possible control is
retained as the wheels do not lock.
However, ABS will not necessarily guarantee shorter braking distances in all
conditions. The braking distance could even be longer if you brake on gravel
or on fresh snow covering a slippery surface.
WARNING
•
The anti-lock brake system cannot defy the laws of physics. Slippery
and wet roads are dangerous even with ABS! If you notice that the ABS is
working (to counteract locked wheels under braking), you should reduce
speed immediately to suit the road and traffic conditions. Do not let the
extra safety features tempt you into taking any risks when driving.
•
The effectiveness of ABS is also determined by the tyres fitted
⇒ page 221.
•
If the running gear or brakes are mo dified, the effectiveness of the ABS
could be severely limited.
Traction control system (TCS)
The traction control system prevents the drive wheels from
spinning when the car is accelerating.Description and operation of the traction control system during acceleration
(TCS)
TCS reduces engine power to help prevent the drive wheels of front-wheel
drive vehicles losing traction during acceleration. The system works in the
entire speed range in conjunction with ABS. If a malfunction should occur in
the ABS, the TCS will also be out of action.
TCS helps the vehicle to start moving, accelerate and climb a gradient in slip-
pery conditions where this may otherwise be difficult or even impossible.
The TCS is switched on automatically when the engine is started. If necessary,
it may be turned on or off pushing the button on the centre console.
When the TCS is off, the warning lamp is lit. The TCS should normally be left
switched on at all times. Only in exceptional circumstances, when slipping of
the wheels is required, should it be disconnected for example•
With compact temporary spare wheel.
•
When using the snow chains.
•
When driving in deep snow or on loose surfaces
•
When the vehicle is bogged-down, to free it by “rocking.”WARNING (continued)
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Operating instructions
Tips and Maintenance
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The TCS should be switched on again afterwards as soon as possible.
WARNING
•
It must be remembered that TCS cann
ot defy the laws of physics. This
should be kept in mind, particular ly on slippery and wet roads and when
towing a trailer.
•
Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by TCS tempt you
into taking any risks when driving, this can cause accidents.Caution
•
In order to ensure that TCS function correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres can
cause the system to reduce engine power when this is not desired.
•
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wh eels and tyres) could affect the effi-
ciency of the ABS and TCS.
Electronic stabilisation programme (ESP)*General notes
The electronic stabilisation programme increases the
vehicle's stability on the road.The electronic stabilisation programme helps to reduce the danger of skid-
ding.
The electronic stabilisation programme (ESP) consists of ABS, EDL and TCS. Electronic Stabilising Program (ESP)*
ESP reduces the danger of skidding by braking the wheels individually.
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 vehi
cle. If the desired course is not being
maintained (for instance, if the car is starting to skid), then the ESP compen-
sates automatically by braking the appropriate wheel.
The forces acting on the braked wheel bring the vehicle back to a stable
condition. If the vehicle tends to oversteer, the system will act on the front
wheel on the outside of the turn.
WARNING
•
It must be remembered that ESP cann ot defy the laws of physics. This
should be kept in mind, particularly on slippery and wet roads and when
towing a trailer.
•
Always adapt your driving style to suit the condition of the roads and
the traffic situation. Do not let the extra safety afforded by ESP tempt you
into taking any risks when driving, this can cause accidents.Caution
•
In order to ensure that ESP functions correctly, all four wheels must be
fitted with the same tyres. Any differences in the rolling radius of the tyres can
cause the system to reduce engine power when this is not desired.
•
Modifications to the vehicle (e.g. to the engine, the brake system, running
gear or any components affecting the wheels and tyres) could affect the effi-
ciency of the ABS, EDL, ESP and TCS.Note
To disconnect using the ESP button ⇒page 153.
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Intelligent technology
174Anti-lock brake system (ABS)The anti-lock brake system prevents the wheels locking during braking
⇒ page 172.Electronic differential lock (EDL)*
The electronic differential lock helps prevent the loss of trac-
tion caused if one of the driven wheels starts spinning.EDL helps the vehicle to start moving, accelerate and climb a gradient in slip-
pery conditions where this may otherwise be difficult or even impossible.
The system will control the revolutions of the drive wheels using the ABS
sensors (in case of an EDL fault the warning lamp for ABS lights up)
⇒page 78.
At speeds of up to approximately 80 km/h, it is able to balance out differ-
ences in the speed of the driven wheel s of approximately 100 rpm caused by
a slippery road surface on one side of the vehicle. It does this by braking the
wheel which has lost traction and distributing more driving force to the other
driven wheel via the differential.
To prevent the disc brake of the braked wheel from overheating, the EDL cuts
out automatically if subjected to excessive loads. The vehicle will continue to
function normally without EDL. For this reason, the driver is not informed that
the EDL has been switched off.
The EDL will switch on again automatically when the brake has cooled down.
WARNING
•
When accelerating on a slippery surface, for example on ice and snow,
press the accelerator carefully. Despite EDL, the driven wheels may start to
spin. This could impair the vehicle's stability.
•
Always adapt your driving style to suit road conditions and the traffic
situation. Do not let the extra safety afforded by EDL tempt you into taking
any risks when driving, this can cause accidents.Caution
Modifications to the vehi cle (e.g. to the engine, the brake system, running
gear or any components affecting the wheels and tyres) could affect the effi-
ciency of the EDL ⇒page 199.The traction control system (TCS)The traction control system prevents the drive wheels from spinning when the
car is accelerating ⇒page 172.Brakes
What factors can have a negative effect on the brakes?New brake pads
New brake pads do not provide optimal performance during the first 400 km,
they must be “run in”. However, the reduced braking capacity may be
compensated by pressing on the brake pedal a little harder. Avoid over-
loading the brakes during run-in.
Wear
The rate of wear on the brake pads depends a great deal on how you drive and
the conditions in which the vehicle is operated. Negative factors are, for
WARNING (continued)
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instance, city traffic, frequent short trips or hard driving with abrupt starts
and stops.
Wet roads; road salt
When the velocity is
over 80 km/h, and the windscreen wipers are on, the
brake system moves the pads towards the brake discs for a few seconds. This
occurs - without warning to the driver - in regular intervals and requires a
more rapid response from the brakes when driving on wet roads.
In certain conditions, such as in heavy rain, or after washing the car or driving
through water, the full braking effect can be delayed by moisture (or in winter
by ice) on the discs and brake pads. The brakes should be dried by pressing
the pedal to restore full braking effect.
The effectiveness of the brakes can also be temporarily reduced if the car is
driven for some distance without using the brakes when there is a lot of salt
on the road in winter. In this case, the layer of salt on the brake discs and pads
has to wear off before braking.
Corrosion
There may be a tendency for dirt to build up on the brake pads and corrosion
to form on the discs if the car is used infrequently, or if you only drive low
mileages without using the brakes very much.
If the brakes are not used frequently, or if corrosion has formed on the discs,
it is advisable to clean off the pads and discs by braking firmly a few times
from a moderately high speed ⇒.
Faults in the brake system
If the brake pedal travel should ever increase suddenly, this may mean that
one of the two brake circuits has failed. Drive immediately to the nearest qual-
ified workshop and have the fault rectified. On the way to the dealer, be
prepared to use more pressure on the brake pedal, and allow for longer stop-
ping distances. Low brake fluid level
Malfunctions can occur in the brake system if the brake fluid level is too low.
The brake fluid level is monitored electronically.
Brake servo
The brake servo amplifies the pressure you apply to the brake pedal. The
brake servo works only when the engine is running.
WARNING
•
When applying the brakes to clean o
ff deposits on the pads and discs,
select a clear, dry road. Be sure no t to inconvenience or endanger other
road users. Risk of accident.
•
Ensure the vehicle does not move whil e in neutral, when the motor is
stopped. Failure to do so could result in an accident.Caution
•
Never let the brakes “drag” by leaving your foot on the pedal when you do
not really intend to brake. This overheats the brakes, resulting in longer stop-
ping distances and greater wear.
•
Before driving down a long, steep gradient, it is advisable to reduce speed
and change to a lower gear (or move the selector lever to a lower gear position
if your car has automatic transmission). This makes use of engine braking
and prolongs the service life of the brakes. If you still have to use the brakes,
it is better to brake firmly at intervals than to apply the brakes continuously.Note
•
If the brake servo is not functioning due to a malfunction, or if the vehicle
has to be towed, you will have to press the brake pedal considerably harder
to make up for the lack of servo assistance.
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Intelligent technology
176•
If you wish to equip the car with accessories such as a front spoiler or
wheel covers, it is important that the flow of air to the front wheels is not
obstructed, otherwise the brakes can overheat.
Braking effect and braking distance
The braking effect and braking distance are influenced by
driving situations and road conditions.The efficiency of the brakes depends directly on the brake pad wear. The rate
of wear of the brake pads depends to a great extent on the conditions under
which the vehicle is operated and the way the vehicle is driven. If you often
drive in town, drive short distances or have a sporty driving style, we recom-
mend that you have the thickness of your brake pads checked by an Approved
Service Centre more frequently than recommended in the Maintenance
Programme.
If you drive with wet brakes, for example, after crossing areas of water, in
heavy rainfall or even after washing the car, the effect of the brakes is less-
ened as the brake discs are wet or even frozen (in winter): The brakes should
be dried by pressing the pedal to restore full braking effect.
WARNING
Longer braking distances and faults in the brake system increase the risk
of accidents.•
New brake pads must be run in and do not have the correct friction
during the first 200 km. However, the reduced braking capacity may be
compensated by pressing on the brake pedal a little harder. This also
applies when new brake pads are fitted.
•
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.
•
On steep descents if the brakes are excessively used they will over
heat. Before driving down a long steep gradient, it is advisable to reduce
speed and change to a lower gear (or move the selector lever to a lower gear
if your vehicle has automatic transmission). This makes use of engine
braking and relieves the brakes.
•
Never let the brakes “rub” by applying light pressure. Continuous
braking will cause the brakes to overheat and will increase the braking
distance. Apply and then release the brakes alternately.
•
Never let the vehicle coast with the engine switched off. The braking
distance is increased considerably as the brake servo does not function.
•
Very heavy use of the brakes may cause a vapour lock if the brake fluid
is left in the system for too long . This impairs the braking effect.
•
Non-standard or damaged front spoilers could restrict the airflow to the
brakes and cause them to overheat. Observe the relevant instructions
before purchasing accessories ⇒page 199, “Modifications”.
•
If a brake circuit fails, the braking distance will be increased consider-
ably. Contact a qualified workshop immediately and avoid unnecessary
journeys.
Power steering (servotronic*)
The power steering assists the driver when turning the
steering wheel (with the engine running).The power steering assists the driver by reducing the force needed to turn the
steering wheel. In cars equipped with servotronic* power steering the degree
of power assistance is regulated electronically according to road speed.
If a fault should occur in the servotronic system the power steering* will still
operate. The degree of power assistance will, however, no longer adapt to
WARNING (continued)
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different speeds. If the electronic regu
lating system is not working properly,
this is most noticeable when turning the steering wheel at low speeds (for
instance when parking) – more effort will be required than usual. The fault
should be corrected by a qualified workshop as soon as possible.
The power steering does not work if the engine is off. In this case the steering
wheel is very hard to turn.
If the steering is held at its turning limit when the car is stationary, this will
place an excessive load on the power steering system, Turning the steering
wheel to its limits places a load on the system, which causes noise. It will also
reduce the idling s peed of the engine.
Caution
When the engine is running, do not tu rn the steering wheel to its limits for
more than 15 seconds. Otherwise, there is a risk of damaging the power
steering.
Note
•
If the power steering should fail at any time or the engine is switched off
(for instance when being towed), the car can still be steered. However, more
effort will be required to turn the steering wheel.
•
If the system is leaking or malfunctioning, please take the car to a quali-
fied workshop as soon as possible.
•
The power steering requires a special hydraulic fluid. The container is
located in the engine compartment (front left). The correct fluid level in the
reservoir is important for the power steering to function properly. The
hydraulic fluid level is checked at the Inspection Service.
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Driving and the environment
178Driving and the environmentRunning-inRunning in a new engine
The engine needs to be run-in over the first 1,500 km.Up to 1,000 kilometres
– Do not drive faster than three quarters of top speed.
– Do not accelerate hard.
– Avoid high engine revolutions.
– Do not tow a trailer.
From 1000 to 1500 km
–Speeds can be gradually increased to the maximum road speed
or maximum permissible engine speed (rpm).During its first few hours of running, the internal friction in the engine is
greater than later on when all the moving parts have bedded in.
For the sake of the environment
If the engine is run in gently, the life of the engine will be increased and its oil
consumption reduced.
Running in tyres and brake pads
New tyres should be run-in carefully for the first 500 km. New
brake pads should be run-in carefully for the first 200 km.During the first 200 km, you can compen sate for the reduced braking effect
by applying more pressure to the brake pedal. If you need to make an emer-
gency stop, the braking distance will be longer with new brake pads than with
brake pads which have been run-in.
WARNING
•
New tyres do not give maximum grip to start with, and require running-
in. This may cause an accident. Drive particularly carefully in the first 500
km.
•
New brake pads must be “run in” and do not have the correct friction
properties during the first 200 km. Ho wever, the reduced braking capacity
may be compensated by pressing on the brake pedal a little harder.
Exhaust gasses purification systemCatalytic converter*To conserve the useful life of the catalytic converter
– Always use unleaded petrol.
– Do not run the fuel tank dry.
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Driving and the environment179
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– For engine oil changes, do not replenish with too much engine oil
⇒page 210, “Topping up engine oil ”.
– Never tow the vehicle to start it, use jump leads if necessary
⇒ page 255.If you notice misfiring, uneven running or loss of power when the vehicle is
moving, reduce speed immediately and have the vehicle inspected at the
nearest qualified workshop. In general, the exhaust warning lamp will light
up when any of the described symptoms occur ⇒page 72. If this happens,
unburnt fuel can enter the exhaust system and escape into the environment.
The catalytic converter can also be damaged by overheating.
WARNING
The catalytic converter reaches very high temperatures! Fire hazard!•
Never park where the catalytic converter could come into contact with
dry grass or inflammable materials under the vehicle.
•
Do not apply additional underseal or anti-corrosion coatings to the
exhaust pipes, catalytic converter or the heat shields on the exhaust
system. These materials could catch fire when the vehicle is driven.Caution
Never fully drain the fuel tank, in this case, the irregularity of the fuel supply
may cause ignition problems. This allow s unburnt fuel to enter the exhaust
system, which could cause overheating and damage the catalytic converter.
For the sake of the environment
Even when the emission control system is working perfectly, there may be a
smell of sulphur from the exhaust unde r some conditions. This depends on
the sulphur content of the fuel used. Quite often the problem can be reme-
died by changing to another brand of fuel.
Diesel engine particulate filter*
The diesel engine particulate filter eliminates soot produced
by burning diesel.The diesel engine dust filter eliminates most of the soot from the exhaust gas
system. Under normal driving conditions, the filter cleans itself. If the driving
conditions do not allow the filter to clean itself (for example, multiple short
trips) the filter will be obstructed by dust and pollen and the indicator for the
diesel engine particulate filter indicator will light ⇒page 79.
WARNING
•
The diesel engine particulate filter may reach extremely high tempera-
tures; it should not enter into contact with flammable materials under-
neath the vehicle. Failure to comply could result in fire.Caution
Vehicles equipped with a diesel engine particulate filter must not be refueled
using biodiesel (RME), given that the fuel system may be damaged.Driving abroadNotesFor driving abroad, the following must be taken into consideration:•
For vehicles fitted with a catalytic converter ensure that unleaded petrol is
available for the journey. See the chap ter “Refuelling”. Automobile organisa-
tions will have information about service station networks selling unleaded
fuel.
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