An apparatus and a method for detecting deformations of a vehicle component on a motor vehicle are disclosed, which are capable of unambiguously determining the location and temporal progression of the deformation, as well as the severity of the deformation, within a very short time after the deformation of the vehicle component begins. A grid module having a grid, an emitter component with a light emitter; and a detector with at least one sensor unit are hereby provided on the vehicle component. A beam path of a light beam between the light emitter and the detector is alternatingly interrupted when the grid is displaced relative to the emitter component due to a deformation of the vehicle component. The detector detects a signal in form of light pulses generated by the interruption of the light beam and the light pulses are transmitted as a time-modulated signal to an evaluation unit.