A method for influencing a control unit by means of a manipulation unit whereby the control unit has at least one microcontroller, at least one memory having a plurality of memory cells and at least one debug interface, and the debug interface has a monitoring functionality for observing the memory content, and by means of the debug interface a first point in time of the control unit for writing a first value to a first memory cell is detected, and a triggering point in time for a processing routine by the manipulation unit is obtained as the result based on the information transmitted to the manipulation unit by the debug interface at the first point in time, and at a second point in time, a second value is written to the first memory cell by the manipulation unit by means of the processing routine via the debug interface before the first memory cell is read by the control unit at a third point in time.