A method and a device for determining a variable describing the speed at
least one driven wheel of a motor vehicle. In this context, variables
describing the respective wheel speeds for the remaining driven wheels of
the motor vehicle, and a variable describing the output rpm of a
transmission of the motor vehicle are determined. To be able to make a
reliable variable describing the speed magnitude of the wheel available to
a traction control system or a vehicle-dynamics control system of a motor
vehicle in spite of the failure of a speed sensor arranged at one of the
wheels, the variable describing the speed for the at least one driven
wheel is determined as a function of the variables describing the
respective wheel speeds of the remaining driven wheels and as a function
of the variable describing the transmission output rpm.
