Intelligent Technology
131
Using the system
Safety
Driving Tips
General Maintenance
Breakdown assistance
Technical Data
Driving TipsIntelligent TechnologyElectronic stability programme (ESP)*GeneralGeneral The ESP aids you maintain control of your vehicle in situations in borderline driving situations such as when negotiating a curve too fast. The risk of skidding is reduced and your vehicle thus offers greater driving stability depending on the conditions of the road surface. This occurs at all speeds. The following systems are integrated into the electronic stability programme:•
Electronic Differential Lock (EDL),
•
Traction control system (TCS),
•
Antilock brake system (ABS),
•
Brake Assist.
Operating principle The ESP switches on automatically when the engine is started and then conducts a self-test. The ESP control unit processes data from the individual systems. It also processes additional measurement data which are supplied by highly sensitive sensors: the rotational velocity of the vehi
cle about its vertical axis, the lateral accel-
eration of the vehicle, the brakin
g pressure and the steering angle.
The direction which the driver wishes to ta
ke is determined based on the steering
angle and the speed of the vehicle and is constantly compared with the actual behaviour of the vehicle. If differences exis
t, such as the vehicle beginning to skid,
the ESP will automatically brake the appropriate wheel. The car is stabilised again by the forces which take effect when the wheel is braked. Intervention into the brake system takes place primarily on the outer front wheel of a vehicle which tends to oversteer (tendency for the rear of the vehicle to break away) while occurs this is on the inner re
ar wheel of a vehicle which tends to under-
steer (tendency to shift out of the curve). This braking control cycle is accompanied by noises. The ESP operates in combination with the ABS
⇒page 135, “Antilock brake system
(ABS)*”. If there is a fault in the ABS system, the ESP also does not operate. The ESP warning light
⇒page 33 lights up in the instrument cluster when there is a
fault on the ESP. Switching off You can switch the ESP off and on again
as you wish, by pressing the button
⇒ fig. 139
. The ESP warning light
⇒page 33 lights up in the instrument cluster
when the ESP is switched off. The ESP 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:
Fig. 139 ESP switch
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Intelligent Technology
132
•
when driving with snow chains
•
when driving in deep snow or on a loose surface
•
when it is necessary to rock a vehicle 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 another combi-
nation of tyres and wheels) can influence the function of the ESP
⇒page 179,
“Accessories, changes and replacement of parts”.Electronic Differential Lock (EDL)* The electronic differential lock pr
events an individual wheel from
slipping.Vehicles fitted with ABS*
can be equipped with electron
ic 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
•
Carefully depress the accelerator 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 warning light comes on, this ma
y 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 the brakes, on chassis or another combi-
nation of tyres and wheels) can in
fluence the function of the EDL
⇒page 179,
“Accessories, changes and
replacement of parts”.
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Intelligent Technology
133
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 135, “Antilock brake system
(ABS)*”. The TCS will not function if a fault exists in the ABS system. The TCS warning light
⇒page 33 lights up in the instrument cluster when there is a
fault on the TCS. Switching off You can switch the TCS off and on again
as you wish by pressing the button
⇒ fig. 140
. The TCS warning light
⇒page 33 lights up in the instrument cluster
when the TCS is switched off.
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 vehicle 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 another combi-
nation of tyres and wheels) can in
fluence the function of the TCS
⇒page 179,
“Accessories, changes and replacement of parts”.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.
Fig. 140 TCS switch
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Fuses and light bulbs
194
Fuse assignment in engine compartment - version 2Certain electrical components are only st
andard on certain vehicle model versions
or only suppliable as optional
equipment for certain models.
Fuse assignment in the dash panelCertain electrical components are only standard on certain vehicle model versions or only suppliable as optional
equipment for certain models.
No.
Power consumer
Amperes
1
Pump for ABS
30
2
Valves for ABS
30
3
Radiator fan 1st stage
30
4
Glow plugs for heating the coolant, relay for secondary air pump
50
5
Engine control unit
50
6
Radiator fan 2nd stage
40
7
Main fuse of the interior
110
8
Dynamo
110 / 150
a)
a)Depending on the engine type and equipment.
Fig. 178 Schematic repre- sentation of fuse box in engine compartment - version 2
No.
Power consumer
Amperes
1
Heating of the exterior mirrors, relay for cigarette lighter, power seats and washing nozzles
10
2
Turn signal lights, Xenon headlight
10
3
Lighting in storage compartment
5
4
Licence plate light
5
5
Seat heating, Climatronic, circulating air flap, exterior mirror heater, cruise control system
7,5
6
Central locking system
5
7
Reversing light, sensors for parking aid
10
8
Phone
5
9
ABS, ESP
5
10
Ignition, S-contact
a)
10
11
Instrument cluster
5
Fig. 179 Schematic repre- sentation of the fuse carrier in the dash panel
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