in the control apparatus of the invention , the power steering can be activated or deactivated by at least one control signal . the invention is characterized in that the control apparatus includes a member for measuring at least one parameter for activation of the power steering system as well as a member for measuring at least one parameter for deactivation of the power steering system . the control apparatus also includes a member for performing a first test to detect whether at least one activation parameter meets an activation condition , and a member for activating the power steering in response to the first test . additionally , the control apparatus utilizes a member for performing a second test to detect whether at least one deactivation parameter meets a deactivation condition , and a member for deactivation of the power steering in response to the second test .