Abstract: A head up display calibration arrangement includes a substrate associated with a windshield. The substrate has a test pattern. A head up display module projects a test display in association with the windshield. The test display at least partially overlaps the test pattern. The test display is projected dependent upon at least one projection parameter value. A camera captures an image of the test display and the test pattern, and transmits an image signal dependent upon the captured image. An electronic processor is communicatively coupled to each of the camera and the head up display module. The processor receives the image signal and determines from the image signal a positional relationship between the test display and the test pattern within the captured image. The processor modifies the projection parameter value dependent upon the determined positional relationship between the test display and the test pattern within the captured image.