A laminated carbon-fibre reinforced divinylcell plate is tested by a nonlinear ultrasonic technique for damage positioning. A high-frequency air-coupled transducer plate is placed above the plate surface, and a low-frequency contact source is fixed at one end. The high-frequency wave field fulfills the open resonator criteria making it localized inside the plate. The nonlinear damage response position is obtained by moving the high-frequency source on either side, having fixed sensors on both plate sides. Further, the nonlinear damage response is measured to change approximately linear with increase in high-frequency, or low-frequency, amplitude.