Intelligent technology
188Brakes
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
T h e r a t e o f we a r o n t h e brake pads depends a great deal on how you drive and
the conditions in which the vehicle is operated. Negative factors are, for
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 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 - at 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 rust has formed on the disks, it is
advisable to clean off the pads and disks 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 off deposits on the pads and discs,
select a clear, dry road. Be sure not to inconvenience or endanger other
road users. Risk of accident.•Ensure the vehicle does not move while 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
a n d ch a n ge to a l o w e r ge a r ( o r m o v e t h e s e l e c t o r le v e r t o a l o w e r g ea r p o s i t i o n
if your car has automatic transmission). This makes use of engine braking
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Driving and the environment191
Safety First
Controls and equipment
Practical tips
Technical Data
your vehicle has automatic transmission). This makes use of engine
braking and relieves the brakes.
•Never let the brakes “slip” by applying light pressure. Continuous
braking will cause the brakes to overheat and the braking distance will
increase. Apply and then release the brakes alternately.•Never let the vehicle run 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 208, “Technical modifications”.•If a brake circuit fails, the braking distance will be increased consider-
ably. Contact a qualified workshop immediately and avoid unnecessary
journeys.
Exhaust gas purification systemCatalytic converter*To conserve the useful life of the catalytic converter
– Always use unleaded petrol.
– Do not let the fuel get too low in the tank.
– For engine oil changes, do not top the reservoir up ⇒page 218,
“Topping up engine oil ”. – Never tow the vehicle to start it, use jump leads if necessary
⇒page 262.
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 75. 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 being driven.Caution
Never fully drain the fuel tank because the irregularity of the fuel supply may
cause ignition problems. This allows 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 under some conditions. This depends on
the sulphur content of the fuel used. Quite often the problem can be solved
by changing to another fuel brand.
WARNING (continued)
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