A method of determining alignment characteristics of a tire and wheel assembly mounted on a vehicle comprises projecting a light plane onto the tire and wheel assembly to form a reference illumination line, receiving a reflected image of the reference illumination line with a photo electric device, and determining a reference distance from the reference illumination line to a noncontact wheel alignment sensor including the photo electric device. The method also includes projecting a plurality of light planes onto the tire and wheel assembly to form a plurality of generally parallel illumination lines, receiving a reflected image of at least some of the generally parallel illumination lines with the photo electric device, and identifying which generally parallel illumination lines are imaged at the receiving step using the reference distance, and determining the orientation of the tire and wheel assembly based on the reflected image of the generally parallel illumination lines.