A motor vehicle with air brakes has not been used for several days. When may you set off at the earliest (vehicle fully loaded)?

You are correct in selecting answer 1. For vehicles with air brakes, especially after standing unused for several days and when fully loaded, you must wait until the pressure warning signals have stopped before driving off. This indicates that the air pressure in the brake system has reached a safe and sufficient level for effective braking. Starting to drive before this point can lead to insufficient braking power, which is dangerous. Always ensure the air pressure warning light or buzzer is off before beginning your journey with such vehicles. The other answers do not guarantee that the full braking power is available, which is why only answer 1 is correct according to German traffic regulations.