A motor vehicle, comprising at least one headlight unit that includes: - an electric actuator for adjusting the inclination of the light beam emitted by the headlight unit; and - an electronic control unit associated to the headlight unit and configured for receiving a control signal (S) and for activating the electric actuator of the headlight unit in such a way as to adjust the inclination of the light beam as a function of said control signal (S), wherein the motor vehicle further comprises: - a main electronic control unit (E) of the motor vehicle; - a system of one or more motor-vehicle airbags, including an airbag electronic control unit (E1); and - a motor-vehicle braking system, including a braking-system electronic control unit (E2), wherein - the main control unit (E) of the motor vehicle is configured for obtaining information on a value of the longitudinal acceleration (Long) of the motor vehicle from the airbag control unit (E1) and for obtaining information on a value of the speed of the motor vehicle (V) from the control unit of the motor-vehicle braking system (E2), said vehicle being characterized in that : - the main control unit (E) of the motor vehicle is configured for calculating the value of the pitch angle (PitchAngle) of the motor vehicle, defined as inclination of the longitudinal axis (X) of the motor vehicle with respect to the road , exclusively on the basis of the values of the longitudinal acceleration (Long) of the motor vehicle, of the speed (V) of the motor vehicle, and of the angle of slope (Slope) of the road, and for generating said control signal (S) for the control unit of the headlight unit on the basis of said calculated value of the pitch angle (PitchAngle) of the motor vehicle; - the main control unit (E) of the motor vehicle is configured for obtaining information on said value of the angle of slope (Slope) of the road from the control unit of the motor-vehicle braking system (E2). - an electric actuator for adjusting the inclination of the light beam emitted by the headlight unit; and - an electronic control unit associated to the headlight unit and configured for receiving a control signal (S) and for activating the electric actuator of the headlight unit in such a way as to adjust the inclination of the light beam as a function of said control signal (S), - a main electronic control unit (E) of the motor vehicle; - a system of one or more motor-vehicle airbags, including an airbag electronic control unit (E1); and - a motor-vehicle braking system, including a braking-system electronic control unit (E2), wherein - the main control unit (E) of the motor vehicle is configured for obtaining information on a value of the longitudinal acceleration (Long) of the motor vehicle from the airbag control unit (E1) and for obtaining information on a value of the speed of the motor vehicle (V) from the control unit of the motor-vehicle braking system (E2), - the main control unit (E) of the motor vehicle is configured for calculating the value of the pitch angle (PitchAngle) of the motor vehicle, defined as inclination of the longitudinal axis (X) of the motor vehicle with respect to the road , exclusively on the basis of the values of the longitudinal acceleration (Long) of the motor vehicle, of the speed (V) of the motor vehicle, and of the angle of slope (Slope) of the road, and for generating said control signal (S) for the control unit of the headlight unit on the basis of said calculated value of the pitch angle (PitchAngle) of the motor vehicle; - the main control unit (E) of the motor vehicle is configured for obtaining information on said value of the angle of slope (Slope) of the road from the control unit of the motor-vehicle braking system (E2). <EOS>