A method and apparatus for operating a valve train of an internal combustion engine having a main camshaft for which at least one rotationally-fixed cam carrier is provided that can be shifted between two axial positions is disclosed. An actuator cooperates with at least one shift gate to axially shift the cam carrier into a target position. The actuator comprises a driver that is extended in the direction of at least one sliding slot of the shift gate to shift the cam carrier. The sliding slot has an ejection ramp in an ejection region that ejects the driver out of the sliding slot until the conclusion of the shift. A voltage induced in the actuator by the ejection is detected, the induced voltage is integrated across a rotational-angle range associated with the ejection region, and a confirmation signal is generated when the integrated voltage exceeds a threshold level.