A method of operating at least one form-locking shifting element of an automatic transmission integrated in a drivetrain which comprises an oil pump that can be driven mechanically by an internal combustion engine and an auxiliary oil pump that can be electrically driven, before start-up of the internal combustion engine. The method including the steps of recognizing the start-up of the combustion engine and, when a start-up of the combustion engine is recognized, controlling the electrically driven auxiliary oil pump and the at least one form-locking shifting element such that, directly after the generation of a defined rotational speed difference of the at least one form-locking shifting element by the internal combustion engine, the at least one form-locking shifting element is engaged.