The invention relates to an energy transfer system for the wireless transfer of energy, having a transmitter unit and a receiver unit separate therefrom, wherein the transmitter unit has a primary coil that is able to be supplied with a supply voltage, and wherein the receiver unit has a secondary coil to which an energy sink is connected via a rectifier, wherein the receiver unit is configured so as to detect a fault case in an energy flow from the secondary coil to the energy sink and, in the fault case, to execute a fault mode (F) having at least one operating parameter (I