quantity is found implausible in step 32 a substitute value is assigned and a bit flag is set in the error storage memory step 34 if the error was found to lie in the gear shifting threshold values an emergency driving strategy is initiated step 36 fig2 illustrates a first example of a system malfunction that can be detected by the inventive method based on a discrepancy between a given control target and the actually occurring behavior of the system an actuator movement from 0 to 15 mm within a set time is given as a target profile 50 the actually occurring actuator displacement 54 closely follows the target profile up to a displacement of 6 mm where it abruptly stops and remains at a constant position as there is now a discrepancy between the targeted and the actually occurring displacement as indicated by the double ended arrow 52 the target profile is adjusted to match the actually occurring displacement this measure is appropriate to protect the system from further damage however the protective measure alone does not provide an error detection unless further steps are taken the detection and evaluation of the malfunction requires registering the fact that the time gradient of the actually occurring displacement profile 54 agrees substantially with the gradient of the target profile 50 while the profiles themselves are in significant disagreement the parameters defining this behavior can be used to evaluate the malfunction fig3 illustrates a second.