Abstract: A method and apparatus for detecting misoriented wheel assemblies in wheel truing machine punch stations. The wheel assemblies for which determination of proper orientation is sought are provided with at least one reference hole, preferably a valve stem hole extending therethrough at a predetermined location. The apparatus includes a light emitting source which is provided in electrical communication with a light detecting target. The light emitting source and the light detection target are disposed in predetermined positions and orientations on opposing sides of the wheel assemblies when received within the punch station. When the light emitting source is engaged during proper wheel assembly orientation, the light beam will pass through the selected reference hole whereupon it will be received and detected by the light detecting target.