A method and an arrangement for controlling a drive unit of a vehicle are suggested. In this method, the control functions for the power of the drive unit and the monitoring of these control functions are carried out by a single microcomputer. A monitoring module, which is separate from the microcomputer, is provided for checking the monitoring functions. The monitoring module transmits test signals to the microcomputer at a given time. The microcomputer then computes the monitoring function on the basis of test data. The result of the computation is transmitted to the monitoring module which checks the operability of the monitoring function in the microcomputer by making a comparison to stored values.