Intelligent Technology
139
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
General The EDL makes it much easier, and sometimes
at all possible, to start off, accelerate
and climb a steep hill when the conditions of the road surface are unfavourable. Operating principle The EDL is activated automaticall
y, 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 greate
r driving force to the other driven wheel.
This control process 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 driven 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
Carefully depress the accelerator when accelerating on uniformly slippery
road surfaces, such as ice and snow. 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 TCS or ESP warning light comes on, this may also indicate a fault in the
EDL. Please have the vehicle inspected as
soon as possible by a specialist garage.
Changes to vehicle (e.g. on engine, on th
e brakes, on chassis or another combina-
tion of tyres and wheels) can in
fluence the function of the EDL
page 184, “Accesso-
ries, changes and replacement of parts”.
BrakesWhat has a negative effect on braking efficiency?Wear-and-tear Wear-and-tear to the brake pa
ds 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 necessary to
have the thickness of the brake pads insp
ected at a specialist garage between the
service inspections. Wet roads or road salt There may be a certain delay before the brakes
take full effect un
der certain conditions
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 possible 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 with
road salt if you have not used the brakes
for some considerable time beforehand. The
layer of salt on the brake discs and brake
pads must first be rubbed 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 firm
ly applying the brakes at a fairly high
speed if you do not make much use of the braking system or if surface corrosion 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 possib
le 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.
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Intelligent Technology
142
You will place great stresses on the power steering system if the steering is turned to full lock when the vehicle is stationary. Turn
ing the steering to full lock in such a situa-
tion will be accompanied by noises. 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 gr
eater physical effort
is required. It is possible that the hydraulic pump of
the power steering will not run due to the low
vehicle network voltage if the battery has gone flat and the engine must started with the help off jump leads. This condition will
be indicated by lighti
ng up of the warning
light. The power steering operates again if the ba
ttery is charged to a specific range when
engine is running. It also op
erates again, if the engine
can be started with its own
battery. If there is a fault in the power steering, the warning light lights up in the instrument cluster
page 26.
Caution
Do not leave the steering at full lock fo
r more than 15 seconds when the engine is
running - risk of damagi
ng the power steering!
Note
Have the steering inspected as soon as possible by a specialist garage if there is a leak or fault in the system.
Tyre pressure monitoring system*The tyre pressure monitoring system compares with the aid of the ABS sensors the speed and also the rolling circumference of the individual wheels. If the tyre inflation pressure is significantly changed and thus the rolling circumference of a wheel, the warning light
lights up in the instrument cluster
page 31. The tyre pressure moni-
toring system functions late or too sensitively if:
the structure of the tyre is damaged,
the vehicle is loaded to one side or with a load on the roof,
the wheels of an axle are loaded heavily (e.g. when towing a trailer or when driving
uphill or downhill),
the vehicle is operated in unfavourable wi
nter conditions or
on an unfirm ground,
snow chains or emergency wheel* are mounted,
the driver has a sporty style of driving (with sharp acceleration and high speed
when cornering). Basic setting of the system After changing the tyre inflation pressures
or after changing one or several wheels, a
basic setting of the system mu
st be carried
out as follows.
Inflate all tyres to the specified inflation pressure
page 178.
Switch on the ignition.
Press button
fig. 131
for more than 2 seconds. While pressing the button,
the warning light
lights up. At the same time the basic values are stored, which is
confirmed with an acoustic sound and then the warning light
goes out.
Fig. 131 Button for setting the tyre inflation pressure control value
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