Method for operating a motor vehicle including an all-wheel drive that can be enabled and disabled by determining an angular acceleration of components, which are uncoupled when the all-wheel drive is disabled

Abstract

A method for operating a motor vehicle including an all-wheel drive that can be enabled and disabled, and a drive train including two clutches actuated by a control unit for enabling and disabling the all-wheel drive, and components rotating between the two clutches, which components are driven when the all-wheel drive is enabled and are uncoupled from the remaining drive train when the all-wheel drive is disabled. In order to allow early detection of defects and, in particular, bearing defects of the rotating components, and to determine the applied drag torque even without knowing the oil temperature, in one embodiment, when the all-wheel drive is disabled, the rotational speed (n) of at least one of the uncoupled components is measured in a time interval, and an angular acceleration of the uncoupled components is determined therefrom.

Dependencies are inferred from the claim text.