Electronic stabilisation program (ESP)
The Electronic Stabilisation Program increases the car's stability.
Description
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 (ESP). The ESP is designed to enhance the control over the vehicle in critical handling situations, such as when accelerating and cornering. It reduces the tendency to skid at all speeds under all road conditions and improves the stability and roadholding of the vehicle. ESP helps the car to start moving, accelerate and climb a gradient in slippery conditions where this may otherwise be difficult or even impossible. The ESP is switched on automatically when the engine is started.
It should normally be left switched on at all times for optimum car stability.
Driving situations
If the car is oversteering (rear wheels losing grip first) the ESP mainly brakes the outside front wheel; if the car is understeering (front wheels losing grip first), the ESP brakes the inside rear wheel and possibly also other wheels. This automatic brake application is accompanied by characteristic noises.
If, when braking, one of the wheels is turning too slowly in relation to the road speed and is close to locking up, the system will reduce the pressure in the brake line to this wheel. The driver is made aware of this control process by a pulsating of the brake pedal and accompanying noise. In this situation it is important to keep the brake pedal fully depressed so the ABS can regulate the brake application - do not “pump” the brake pedal. However, the ABS will not necessarily guarantee shorter stopping distances in all conditions. For instance, on loose gravel or fresh snow on top of an icy surface the stopping distance with ABS may even be slightly longer.
Whenever it detects a significant difference in the speed of the driven wheels of one axle (for example, if the road is slippery on one side) the electronic differential lock (EDL) applies the brake to slow down the spinning wheel so that more of the power is directed to the other wheels. This function is active up to about 100 km/h. The brake system will make noises while it is working.
If one wheel has less grip and starts spinning (for instance, if one of the driven wheels is on ice), press the accelerator hard until the car starts moving.
If the wheels start to spin, the traction control system (ASR) automatically reduces the engine torque to match the amount of grip available.
Activating the sport mode
If required (for instance if you want to use the launch control), you can switch the traction control system (ASR) and electronic stabilisation program (ESP) to sport mode by pressing the button once. The ESP warning lamp will light up and the message ASR off will appear in the driver information system display. The amount of wheel slip is regulated according to the road speed. You should only use this feature if your driving ability and traffic conditions allow you to do so safely.
Switching off the ESP and traction control system (ASR)
To switch off the ASR and ESP in certain situations (e.g. when driving with snow chains, in deep snow, or on a loose surface, or when rocking the car backwards and forwards to free it from mud) press the button for longer than 3 seconds. The ESP warning lamp will light up and the message ESP switched off will appear in the driver information system display. You should only use this feature if your driving ability and traffic conditions allow you to do so safely.
Switching on the ESP/traction control system (ASR)
To activate the ASR/ESP, press the button again.
Overheating of the brakes
To prevent the disc brake of a braked wheel from overheating, the EDL cuts out automatically on the wheel in question if subjected to excessive loads. The car remains operational and will behave in the same way as a car without EDL. The EDL will switch on again automatically when the brake has cooled down.
WARNING
•
The grip provided by the ESP, ABS, EDL and ASR systems is still subject to the physical limits of adhesion. Always bear this in mind, especially on wet or slippery roads. If you notice the systems cutting in, you should reduce your speed immediately to suit the road and traffic conditions. Do not let the extra safety features tempt you into taking any risks when driving – this can cause accidents.
• Please remember that the accident risk always increases if you drive too fast, especially in corners or on a slippery road, or if you follow too close behind the vehicle in front of you. Please bear in mind that even ESP, ABS, EDL and ASR cannot compensate for the increased accident risk.
• When accelerating on a uniformly slippery surface (for instance all four wheels on ice or snow), press the accelerator gradually and carefully. The driven wheels may otherwise start to spin (in spite of the EDL), which would impair the car's stability and could lead to an accident.
• Please note that, when the traction control system (ASR) or ASR/ESP is switched off, the driven wheels may start to spin, causing the vehicle to lose grip, in particular on slippery or wet roads - danger of skidding!
Note
• In the event of a malfunction in the rear spoiler system or in the Audi magnetic ride, it may not be possible to switch off the traction control system (ASR) or ASR/ESP, or the ASR/ESP may be reactivated automatically from the deactivated status.
• If a malfunction should occur in the EDL, this is indicated by a warning lamp.
• Some racing circuits (e.g. with banked curves) can affect the behaviour of the ESP.