A method managing a device distributing engine torque between main and secondary wheel sets of a motor vehicle, the distributing device including an actuator distributing engine torque, a control unit exhibiting plural distribution modes of the engine torque and adopting one distribution mode as a function of a variable and a button selecting a distribution mode delivering an information item representative of the button position, the control unit determining, in regular operation, the variable, as a function of the information item; the method includes: detecting potential failure of the selection button, including verifying consistency of the information item; activation of degraded mode of operation, when a failure of the button is detected, in which a constant value is allocated to the variable; during degraded operation, monitoring end of failure, including verifying consistency of the information item; activation of regular mode of operation, when end of failure is detected.