Xenon

Conventional halogen light technology has been largely exhausted as regards light intensity and lighting characteristics. Xenon lights provide significant improvement in this area. Xenon headlights make night driving easier, thanks to the fact that the spectrum of xenon light is similar to daylight, thus providing a high level of safety. Xenon headlights are notable for their far range and perfect lateral spread. Further advantages include low energy consumption and the durability of the bulbs for the vehicle’s entire service life. The source of light is a so-called gas-discharge lamp. An arc-over between two electrodes in the xenon-gas atmosphere in the lamp bulbs, results in an ionized gas tube through which electric current flows. This causes the gaseous mixture to glow in the form of an electric arc. A sophisticated electronics system is necessary for the operation of these bulbs in order to generate the high ignition voltage of between 18,000 and 30,000 volts, to guarantee constant operation at an output of just 35 watts or automatic re-ignition. Xenon headlights deliver considerably more light than halogen headlights and make night driving, particularly in poor weather conditions, safer and less tiring for the driver’s eyes.

Cornering Lights

The bi-xenon headlights with dynamic cornering light provides up to 90 % better illumination of corners or the turn-off area. Above a speed of approx. 15 km/h, the headlight beams follow the steering angle of the vehicle's steering wheel with the aid of small servomotors in the headlight units. The maximum swivel angle of the dynamic cornering light is 15 degrees. The steering movement of the headlight units is controlled by means of the signals from the steering angle sensor, among other things. The improved visibility enables obstacles to be detected earlier, and the driver gains additional reaction time. This reduces the risk of an accident quite considerably.

Front & Rear Parking Sensors

Park distance control is a parking aid to warn of the distance from obstacles at the front and rear. A repeated warning signal tells the driver how far the vehicle is from the obstacle. As the gap decreases, the frequency of the acoustic signal increases. It begins signalling when the vehicle is 1.60 metres from the obstacle. When only 20 centimetres of manoeuvring room remains, the warning sound becomes continuous. The system operates through up to 12 ultrasonic sensors mounted in the front and rear bumpers. The sensors emit and receive pulses in the 40,000 Hz range. When a pulse contacts an obstacle, it is reflected. The sensor records the echo. The electronic evaluation system calculates the distance between the obstacle and the vehicle from the time lag between the pulse and the echo. The parking distance control at the front can be switched off to adjust to particular traffic situations, such as in stop and go traffic. The rear ParkPilot unit is automatically switched on when the reverse gear is engaged.

8 Airbags

Airbags combine with the seat belts to reduce the risk of severe head and chest injuries in collisions with a certain severity. If the crash sensors register an impact that exceeds the value needed to trigger the airbags, the airbag control ignites the gas generator. This inflates the airbags, which are located in the steering wheel and the dashboard in front of the front-seat passenger within 30 to 40 milliseconds. When inflated, these airbags cushion the head and upper body and distribute the resulting loads over as large an area as possible. Just 120 milliseconds later, the gas escapes and the airbag collapses. Reducing the amount of head and neck movement helps to reduce the risk of injury. A more advanced version of the conventional system featuring two-stage deployment of the front airbags can be found, for example, on the Volkswagen Phaeton. The carefully defined inflation of the airbags in two stages, depending on the severity of the impact, is designed to reduce the load placed on the driver and front passenger in the event of an accident. However, optimum protection can only be achieved if the occupants are properly wearing their seat belts, as the airbags and the seat belt tensioners together form a finely tuned safety system. In addition to the front airbags, side airbags and a head airbag system are also available.

ABS/ESP

The anti-lock braking system prevents the wheels from locking up during an emergency stop or when braking on a slippery surface, ensuring that drivers are still able to steer the vehicle. When the wheels lock up, they are no longer able to transmit cornering forces, meaning that the driver loses control of the vehicle. To prevent this from happening, the ABS control unit uses wheel speed sensors to monitor the rotational speed of all of the vehicle's wheels. If there is a risk of a wheel locking up, a solenoid valve in the anti-lock braking system's central control unit reduces the brake pressure applied at the wheel in question until it starts to rotate freely again. The pressure is subsequently increased to the lock-up threshold again. The vehicle remains stable and controllable. On the latest anti-lock braking systems, as fitted on all Volkswagen models, this process is repeated several times a second. The driver knows when the anti-lock braking system is at work because the brake pedal pulsates slightly. Within the anti-lock braking system's scope of operation, the vehicle can be steered without difficulty, even when braking at full power, allowing the driver to take evasive action to avoid colliding with any obstacles in the road ahead. The "off-road" ABS function featured in the Touareg is a special algorithm programmed into the ABS control unit which is activated automatically only when driving in extreme off-road terrain (vehicle must be travelling at less than 5 km/h with the centre differential locked, for instance). With "off-road" ABS, the wheels can lock up briefly before the system reduces the brake pressure. This allows time for a small wedge of material from the ground (such as gravel or sand) to build up in front of the wheels, which then increases the braking effect. The Touareg remains steerable at all times while stopping distance is significantly shorter.

Rain Sensors

The Volkswagen rain sensor automatically regulates the intermittent wipe intervals of the windscreen wiper according to the intensity of the rain. The sensor is housed in the base of the interior mirror. It consists of a number of infrared light-emitting diodes (LEDs) and a central photodiode. The light emitted by the LEDs is reflected by the windscreen onto the photo sensor. The more drops of water there are on the windscreen, the less light the sensor receives. This information is passed to an electronic control unit which adapts the wipe intervals of the windscreen wiper accordingly. The sensitivity of the sensor can be additionally customised by way of a selector switch. The rain sensor is designed such that minor defects, dirt and ageing of the windscreen do not impair its functionality. The benefits of the rain sensor are comfort and safety. The driver is able to concentrate fully on the road, without having to worry about adjusting the wipe interval. This is a major boost to safety, particularly when visibility is suddenly impaired while overtaking trucks on a wet road, for example.

Automatic Head Lamps

The automatic headlight range control ensures an optimum headlight setting and illumination of the road ahead. The headlight range control maintains a constant headlight range regardless of the vehicle load, preventing oncoming traffic from being dazzled. The control function automatically adjusts the headlights' angle of inclination depending on the current vehicle load. There are two different types of automatic headlight range control system: static and dynamic systems. Whereas the static systems are able to compensate for the extra weight of the passengers and their luggage, dynamic systems also correct the headlight setting when pulling away, accelerating and braking. On static systems, the control unit processes the signals supplied by the electronic speedometer and the ABS control unit, as well as the tilt sensor signals it receives. This enables the system to determine whether the vehicle is stationary or travelling at a constant speed. Volkswagen's dynamic headlight range control system maintains correct headlight settings in all driving situations. The control unit is also capable of distinguishing the change in the speed signals produced by the vehicle accelerating and braking. Processing these extra signals calls for a far more powerful control unit. The motor actuator also adjusts at a higher speed, allowing headlight range adjustment to be completed in a few fractions of a second. Automatic headlight range adjustment is a legal requirement on vehicles fitted with xenon headlights.

Anti Theft Warning With Interior Survelliance

In order to protect against theft, more and more vehicles are being equipped with systems that are primed and deactivated again by means of a coded radio remote control and sound an audible alarm when unauthorised entry is detected by contacts on the doors, engine compartment and luggage compartment or by ultrasonic motion sensors or current consumers in the vehicle's interior. The ultrasonic system also detects attempted vehicle entry through a broken window.