Patent ID: 8702557

Claim:
A method for controlling a switchable planetary gear set ( 12 ) in a belt drive ( 3 ) of an internal combustion engine ( 2 ) in a motor vehicle, having a sun gear ( 15 ) which is fixedly connected to a belt pulley, a ring gear ( 13 ) which can be connected fixedly with respect to a housing by means of a brake ( 14 ) which is activated by an electrically operated actuator ( 22 ) which is effective along a travel distance (x) which is monitored by a relative distance sensor ( 33 ), and a web ( 17 ) which is connected to a crankshaft ( 8 ) of the internal combustion engine ( 2 ) and rotatably accommodates planetary gears ( 16 ), wherein situated between the sun gear ( 15 ) and the web ( 17 ) is a freewheeling mechanism ( 10 ) which can be switched and rolled over in both directions and is switched by the same actuator ( 22 ) along the travel distance (x), the method comprising: ascertaining the travel distance (x) of the actuator ( 22 ) by means of travel distance signals of the relative distance sensor ( 33 ); referencing the relative distance sensor ( 33 ) to an absolute value by means of at least one reference pass of the actuator ( 22 ); analyzing an electrical behavior of the actuator ( 22 ) at at least one specified travel point (WP) of the travel distance (x); and, establishing the at least one specified travel point (WP) as an absolute value depending on the electrical behavior of the actuator ( 22 ).