ARE the traffic lights going to change just before you reach them?

Drivers are faced with this dilemma every day and have to be prepared to stop suddenly or risk going through them at red.

But Audi has come up with a new system which gives drivers a warning of what the lights ahead are going to do and how much time there is to prepare to stop or safely drive on.

Audi is the first car manufacturer to connect a car to a city infrastructure. In Las Vegas Audi A4 and Q7 models are now able to display traffic light phases directly in the car and introduction of the system is planned in Europe.

The German car firm believes that its traffic light information system optimises traffic flow, saves valuable time and reduces environmental impact and if you know in advance when a traffic light will switch from red to green, your driving is more relaxed and efficient.

As a first step, all Audi A4 and Q7 models produced for the US market since June this year and equipped with Audi Connect have this function on board.

In the USA, municipal traffic management centres will communicate the traffic-light data to Audi's project partner Traffic Technology Service. Here the data is prepared and sent to the car's on-board computer via a fast Internet connection.

In the Audi virtual cockpit or head-up display, drivers see whether they will reach the next light on green while travelling within the permitted speed limit. If not, a countdown is provided of the time remaining until the next green phase- and drivers can throttle back in good time.

Michael Zweck, project manager for Audi traffic light information pilot projects in Europe, said: "In our tests the number of cars that had to brake to a standstill in traffic fell by around 20 percent. This saved time for the driver and also made fuel savings of about 15 per cent in the pilot project."

Audi also intends to introduce the technology in Europe. In Berlin, Ingolstadt, Garmisch-Partenkirchen and Verona there have already been pilot projects. In Berlin alone, some 700 traffic lights in the inner city have been connected to the service.

Across Europe, however, unified data standards and digital infrastructure do not exist at the moment.

Mr Zweck said: "In Europe highly diverse traffic technology is in use, as the infrastructure has developed locally. We are working on harmonisation of the data that has been prepared. After that has been done, we can provide the same service."