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Close the windows and glass sunroof
Driving with the glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

After the ignition is switched off
The roof can still be operated for approx. 1 minute, as long as no door has been opened. ...

The concept
The system issues a two-phase warning of a danger of collision at speeds above approx. 10 mph/15 km/h. The collision warning is available even if cruise control has been deactivated. It resp ...