A method for monitoring the short-circuiting switching device of a three-phase motor (3) for driving vehicles, which is fed from a DC voltage source (1) via a controlled converter (2), wherein the short-circuiting switching device (5) actuated by a control logic (6) is connected to the inputs of the motor, and the motor currents and/or motor voltages are measured, and a predetermined test pattern, which is different from the voltage/current profiles during operation, is generated with the aid of the controlled converter (2) during a test phase and is supplied to the motor (3), the short-circuiting switching device is actuated for the activation thereof, the current and/or voltage profile is detected during the test phase by opening and closing of short-circuiting contacts and, on the basis of the current and/or voltage distribution in the individual motor phases, the correct open-ing/closing of the short-circuiting contacts is detected and evaluated.