Patent ID: 8831804

Claim:
A method of controlling an automatic geared transmission of a motor vehicle by a safety function wherein the vehicle includes, on an input side of the transmission, a hybrid drive comprising a combustion engine and an electric motor and at least a controllable friction clutch and, on the output side of the transmission, wheels which are driven via an axle drive, the method of the safety function comprising the steps of: activating a safety function only after determining that: a vehicle rolling speed (v Roll ) is less than a predetermined minimum vehicle rolling speed (v min ), and a rotational speed (n M ) of at least one of the combustion engine and the electric motor is greater than a determined minimum rotation speed (n min ), and the transmission is in a neutral gear, and a brake is disengaged; and exiting the safety function when at least one of: a shift actuation element is actuated (x SBE ≠0); a throttle is actuated (x FP ≠0); and a brake pedal is actuated (x BP ≠0); while the safety function is activated, if the vehicle rolling speed (v Roll ) exceeds a predetermined speed limit (v Gr ), then engaging a starting gear by a sequence of steps selected from the group of sequences of steps consisting of: (A) engaging (G l =G Anf ) the starting gear, and (B) disengaging (x K =0) the friction clutch, engaging (G l = Ganf ) the starting gear, and reengaging (x K =1) the friction clutch, thereby providing drag torque braking of the vehicle by the at least one of the combustion engine and the electric motor; wherein the safety function only provides for activation when the motor vehicle is unattended in one way or another and when the motor vehicle is not traveling in any direction.