Patent ID: 7930935

Claim:
A method for diagnosing the functioning of a motor vehicle level control system ( 1 ) comprising a control unit ( 10 ) and at least one electrically actuated valve ( 2 a , 2 b , 14 , 26 ) with an open state permitting an exchange of pressure medium from the one side of the valve to the other side of the valve and with a closed state preventing an exchange of pressure medium, the method comprising the steps of changing the state of the valve ( 2 a , 2 b , 14 , 26 ) while the valve is in the motor vehicle level control system of a motor vehicle during an operation of the motor vehicle, measuring at least one quantity (U, I) influencing the output of the valve ( 2 a , 2 b , 14 , 26 ) during the change of state, making a comparison between the measured quantity (U, I) influencing the output of the valve ( 2 a , 2 b , 14 , 26 ) and a reference, determining in the control unit ( 10 ), on the basis of the comparison, whether the valve ( 2 a , 2 b , 14 , 26 ) has performed the change of state, wherein the reference is a member of the group consisting of an electric current reference curve, a family of electric current characteristics, and an electric current limit value and wherein the method is performed whenever a level control action is to be performed.