Power supply for a motor vehicle

Power supply device for a motor vehicle, with a locking switch (1), a collision sensor (2) for detecting an impact of a motor vehicle, a latching relay (3), which is controlled by the locking switch (1) and turned ON and OFF, and (a contactor 4) (for interrupting an output circuit 11) when the latching relay is turned OFF, wherein, when an interrupt signal for interrupting the output circuit (11) from the crash sensor (2) is discharged or when the locking switch (1) of oN is turned OFF is the contactor (4) is turned OFF to interrupt the output circuit (11), characterized, that a switching element (6) with each excitation coil (4a) of the contactor (4) is connected in series and by the interrupt signal of the collision sensor (2) is turned ON and OFF, wherein when the collision sensor (2) outputs the interrupt signal, the switching elements (6) are turned OFF and the contactor (4) by interrupting a current of the excitation coil (4a) in the ...