A method for determining an indicator for a blindness of a radar sensor, includes: controlling the radar sensor to transmit a transmission signal in the form of at least two successive frequency ramps having the same ramp slope and in the same frequency range, and to receive detection signals associated with the frequency ramps; examining, for multiple frequencies, whether a ratio between the received powers in the frequency spectra of the received signals, at a respective frequency, corresponds to a ratio between the transmission powers of the associated frequency ramps; and determining an indicator for a blindness of the radar sensor based on the result of the examinations.