Procedure for engaging a form-locking shift element to realize a gear in an automatic transmission, whereat at least one further friction shift element is to be engaged to realize the gear to be activated

A method of engaging a form-locking shift element so as to implement a target gear in an automatic transmission that comprises first, second, third and fourth shift elements, the first shift element is the form-locking shift element, the second shift element is a frictional shift element and the fourth element is a synchronizing shift element, and the first, the second, and the third shift elements are engaged and the fourth shift element is disengaged in the target gear, the method comprising the steps of:

• actuating the fourth shift element to synchronize the first shift element;
• engaging the second shift element and subsequently disengaging the second shift element such that the second shift element operates with slip to ensure engagement of the first shift element;
• adjusting the second shift element to a current transmission limit plus a pressure offset so that a rotational speed difference at the second shift element becomes zero;
• and
• reducing pressure at the second shift element, as a function of a time-point at which claws of the first shift element engages, such that the second shift element operates with slip to reduce torque at the claws of the first shift element and enable the claws of the first shift element to be biased into a fully engaged end position.