A device for protecting electronic modules in a multivoltage on-board electrical wiring system comprising a first accumulator of a low on-board electrical wiring system voltage, against short circuits after a high on-board electrical wiring system voltage, consisting of a transistor whose drain-source path is inserted between the control device connection and the electronic module connection. The source connection of the transistor is linked to the electronic module connection. A gate resistor and a diode guiding the current in the direction of the plus pole of the first accumulator are parallel-mounted between the gate connection of the transistor and the plus pole of the accumulator. A Zener diode is arranged between the gate connection and source connection of the transistor.