Abstract: A method tests a switching state of a circuit breaker device (10) for establishing/breaking a connection of two circuit areas (12, 14), especially in a vehicle. The circuit breaker device includes at least one MOSFET switching element (20) with a source terminal (22) connected with one of the circuit areas (12, 14) and a drain terminal (24) connected with another of the circuit areas (12, 14). A gate driver (26) is associated with the switching element (20) for switching into a connection switching state. The method includes applying a testing voltage pulse to the drain terminal, detecting a voltage drop between the drain terminal and the source terminal, comparing the voltage drop detected with a voltage reference or/and with a time reference, and determining, based on the comparison, an actual switching state of the at least one MOSFET switching element (20) being subjected to the switching state test.

Abstract: A method tests a switching state of a circuit breaker device (10) for establishing/breaking a connection of two circuit areas (12, 14), especially in a vehicle. The circuit breaker device includes at least one MOSFET switching element (20) with a source terminal (22) connected with one of the circuit areas (12, 14) and a drain terminal (24) connected with another of the circuit areas (12, 14). A gate driver (26) is associated with the switching element (20) for switching into a connection switching state. The method includes applying a testing voltage pulse to the drain terminal, detecting a voltage drop between the drain terminal and the source terminal, comparing the voltage drop detected with a voltage reference or/and with a time reference, and determining, based on the comparison, an actual switching state of the at least one MOSFET switching element (20) being subjected to the switching state test.