In a magnetic resonance system and method for checking the positioning of an examination subject, with an image acquisition unit that acquires images of an examination subject by means of nuclear magnetic resonance, an image processing unit automatically searches the acquired images of the examination subject for geometric figures in the examination subject that could result in closed current loops in the examination subject, and an information unit automatically informs operating personnel of the magnetic resonance system when the image processing unit has detected a geometric figure that could lead to closed current loops in the acquired images.