Volkswagen Polo Owners Manual: Brake support systems

First read and observe the introductory information and safety warnings 

The brake support systems ESC, ABS, BAS, TCS and EDL only function when the engine is running. They make a considerable contribution to active driving safety.

Electronic stabilisation programme (ESC)

The ESC helps to reduce the risk of skidding and to improve driving stability by braking individual wheels in certain driving situations. The ESC detects critical driving situations such as oversteer, understeer and wheelspin. The system supports the stabilisation process for the vehicle by targeted braking or by reducing engine torque.

ESC has its limitations. It is important to realise that ESC cannot overcome the laws of physics. ESC will not be able to assist in every situation faced by a driver. For example, ESC will not be able to assist every time that there is a sudden change in the road surface quality. If a section of dry road is suddenly covered with water, mud or snow, ESC will not be able to assist in the same manner as on a dry road. If the vehicle aquaplanes (drives on a layer of water rather than on the road surface), ESC will not be able to assist in steering the vehicle as the contact to the road surface has been interrupted and it is therefore no longer possible to steer or brake the vehicle. When driving at speed through bends, particularly on stretches of road with many bends, the ESC will not always be able to process complicated driving situations as effectively as at lower speeds. When towing a trailer, ESC is not able to assist the driver in regaining control over their vehicle.

Always adapt your speed and driving style to suit visibility, weather, road and traffic conditions. ESC cannot defy the laws of motion, improve the available power output, or keep the vehicle on the road if insufficient care and attention on the part of the driver causes the vehicle to leave the road. Instead, ESC increases the possibility of keeping the vehicle under control and, in extreme on-road driving situations, it assesses the driver’s steering input and helps the vehicle to continue in the required direction. If the vehicle is driving at a speed that leads it to leave the road before the ESC can provide any kind of support, the ESC will be unable to provide any assistance.

The ABS, BAS, TCS and EDL systems are integrated into the ESC. The ESC is always on. In certain situations when the traction achieved is not sufficient, TCS can be switched off by pressing the ASR (TCS) button  . Always ensure that ASR (TCS) is switched back on again once traction is sufficient.

Anti-lock brake system (ABS)

The ABS prevents the wheels from locking when the brakes are applied up until the point where the vehicle is nearly stationary and assists the driver in steering the vehicle and keeping it under control. This means that the vehicle is less likely to spin, even when the brakes are depressed fully:

• Depress and hold the brake pedal with force. Do not take your foot off the brake pedal or reduce the force on the brake pedal.

• Do not pump the brake pedal or reduce the pressure on the brake pedal.

• Steer the vehicle while the brake pedal is fully depressed.

• The ABS will switch off when the brake pedal is released or if the pressure on the brake pedal is reduced.

If the ABS is taking corrective action, there is a pulsing movement in the brake pedal and some noise. However, ABS will not necessarily guarantee shorter braking distances in all conditions. The braking distance could even be longer when braking on gravel or on fresh snow covering an icy or slippery surface.

Brake Assist system (BAS)

The Brake Assist system can help to reduce the braking distance. The Brake Assist system reinforces brake pressure when the driver depresses the brake pedal quickly in an emergency situation. As a result, full braking power is made accessible very quickly, brake pressure is increased and the braking distance reduced. This means that the ABS is activated more quickly and more effectively.

Do not reduce the pressure on the brake pedal. The Brake Assist system will switch off the brake servo automatically when the brake pedal is released or if the pressure on the brake pedal is reduced.

Traction control system (TCS)

The TCS reduces the engine output if wheelspin occurs and adapts the output to suit road surface conditions. TCS helps the car to start moving, accelerate and climb gradients in unfavourable road conditions.

The TCS can be switched on and off manually   .

Electronic differential lock (EDL and XDL)

The EDL is available for normal driving on straight roads. EDL brakes the wheel that has lost traction and distributes the driving force to the other drive wheels. To prevent the disc brake of the braked wheel from overheating, the EDL cuts out automatically if subjected to excessive loads. The EDL will switch on again automatically when the brake has cooled down.

The XDL function is an extension of the electronic differential lock. The XDL does not respond to traction control, but rather to the reduction of load on the inside front wheel when driving through a bend at high speed. XDL will apply the brake on the inside front wheel to prevent it from losing traction. This will improve traction, helping the vehicle to remain in the required lane longer.

WARNING

Driving fast on icy, slippery or wet roads can lead to a loss of control of the vehicle and could cause serious injury to the driver and passengers.

• Adapt your speed and driving style to suit visibility, weather, road and traffic conditions. Do not let the extra safety afforded by the brake support systems ABS, BAS, EDL, TCS and ESC tempt you into taking any risks when driving.

• The brake support systems cannot defy the laws of motion. Slippery and wet roads will remain dangerous, even when the ESC and other systems are active.

• Driving too fast on wet roads can cause the wheels to lose contact with the road surface and aquaplane. The vehicle cannot be braked, steered or controlled once it has lost contact with the road surface.

• Brake support systems cannot prevent an accident if, for example, you are driving too close to the vehicle in front or are driving too fast for the individual situation.

• Although the brake support systems are very effective and can help to control the vehicle in difficult driving situations, please always remember that the driving stability of the vehicle depends on the tyre grip.

• When accelerating on a slippery surface, for example on ice and snow, press the accelerator carefully. The wheels can spin even when brake support systems are active, and this can lead to a loss of control of the vehicle.

WARNING

The effectiveness of ESC can be reduced considerably if other components and systems which affect driving dynamics are not serviced properly or are not functioning properly. This also applies, but not exclusively, to the brakes, tyres and other systems that have already been named.

• Please always remember that modifications and changes to the vehicle can affect the functioning of the ABS, BAS, TCS, EDL and ESC systems.

• Alterations to the suspension system or the use of non-approved wheel and tyre combinations can affect the function of ABS, BAS, TCS, EDL and ESC and reduce their effectiveness.

• Suitable tyres are also crucial if ESC is to function optimally   .

The ESC and TCS can only function properly if all 4 wheels are fitted with the same tyres. Any differences in the rolling radius of the tyres can cause the system to reduce engine power unexpectedly.

If there is a fault in the ABS, the ESC, TCS and EDL will also stop working.

Control processes running in the systems described may cause operating noises.