Intelligent Technology; Electronic Stabilisation Program (Esp) - Audi S5 Owner's Manual

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Intelligent technology

Intelligent technology

Electronic stabilisation program (ESP)

General notes
The electronic stabilisation program increases the car's
stability on the road.
The ESP is designed to enhance the control over the vehicle in crit-
ical handling situations, such as when accelerating and cornering.
It reduces the tendency to skid under all road conditions and
improves the stability and roadholding of the vehicle. The system
works at all speeds.
The anti-lock brake system (ABS), the electronic differential lock
(EDL) and the traction control system (ASR) are all integrated into
the electronic stabilisation program.
How the system works
The ESP control unit processes data from the three integrated
systems. It also processes additional inputs provided by other high-
precision sensors. These register the vehicle's rotation about the
vertical axis (yaw rate), lateral acceleration, brake pressure and
steering wheel angle.
The system uses the steering wheel angle and road speed to calcu-
late the changes of direction intended by the driver, and constantly
compares them with the actual behaviour of the vehicle. If the
desired course is not being maintained (for instance, if the car is
starting to skid), then the ESP compensates automatically by
Fig. 192 Without MMI:
braking the appropriate wheel.
Centre console with
ESP switch
The forces acting on the braked wheel effectively bring the car back
to a stable condition. If the car is oversteering (rear wheels losing
grip first) the brake application is concentrated on the outside front
wheel; if the car is understeering (front wheels losing grip first), ESP
brakes the inside rear wheel. This automatic brake application is
accompanied by characteristic noises.
The ESP works in conjunction with the ABS ⇒ page 187. If a
malfunction should occur in the ABS, the ESP will also be out of
action.
Fig. 193 Centre
console with ESP
Switching on
switch
The ESP is switched on automatically when the engine is started
and performs a self-test routine. As soon as this routine is complete,
the system switches back to normal operating mode. You can press
the button ⇒ fig. 192 or ⇒ fig. 193 to switch on the ESP or traction
control system (ASR) if they have been switched off. The message
ESP/ASR on will appear briefly in the display.