A method of detecting manipulation of a programable memory device of a digital controller for a motor vehicle is described; data and control programs for operation of the controller and for control/regulation of certain functions of the motor vehicle can be stored in the memory device. To permit especially reliable detection of manipulation in the simplest possible way, in conjunction with each programing/reprograming operation of the programable memory device, information regarding the programing/reprograming operation is stored in a separate memory area of the memory device where only reading and programing are possible, and in order to detect manipulation, the content of the separate memory area is read out and compared with given information.