the front and rear tyres of the vehicle it is necessary to determine the pressures of the tyres r 1 r 5 for a third driving dynamic state of the vehicle as in the case of the second driving dynamic state it is possible to measure the tyre pressures for a predetermined third driving dynamic state or for an arbitrary driving dynamic state at a predetermined interval of time from the preceding tyre pressure measurement the predetermined interval of time in this case can be the same as or different from the interval of time between the first and second pressure measurements for the reasons stated above the third tyre pressure measurement is preferably performed for an arbitrary driving dynamic state at an interval of time from the second tyre pressure measurement the intervals of time being the same for reasons of simplicity if in the case of the third tyre pressure measurement the vehicle is travelling straight forward at a constant positive acceleration the following information is supplied to the processor device cpu since u2014 by comparison with the tyre pressures in the first driving dynamic state u2014 the tyres r 1 and r 4 have a decreased tyre pressure and the tyres r 2 and r 5 have an increased tyre pressure it is shown that the tyre.