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

Your answer is correct. Before setting off in a fully loaded motor vehicle with air brakes that has not been used for several days, you must wait until the pressure warning signals have stopped. This ensures that the air pressure in the braking system has reached a safe level to provide full braking power. The warning signals indicate that the pressure is too low for safe operation. Waiting for the spring-loaded brake to release or for a 3 bar reserve pressure is not the main safety indicator in this situation. The key rule is to only start driving when the pressure warning device signals have stopped, confirming that the brake system is properly pressurized.