A plug connector having two housings and a locking clip and a catch for locking and unlocking the two housings is provided, wherein the locking clip is rotatably mounted on one of the two housings. The catch comprises at least one part and is arranged on the locking clip. It has a folded-out position and a folded-in position. In addition, the catch has at least one articulated connection and is formed in the shape of a Z-beam or Z-support. The catch prevents inadvertent opening and closing of the locking clip with simultaneously simple handling for the user. Methods for locking and unlocking a plug connection are also provided. The catch 2 when folded down (FIG. 1) blocks the locking clip 1 against movement to an unlocked position. The catch 2 when folded upward (FIG. 2) permits free motion of the locking clip 1 to the unlocked position to permit separation of the housings.