A method of detecting manipulation of a programmable 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 programming/reprogramming operation of the programmable memory device, information regarding the programming/reprogramming operation is stored in a separate memory area of the memory device where only reading and programming are possible, and in order to detect manipulation, the content of the separate memory area is read out and compared with given information.