Circuit Protection Devices

Saturn vehicles use four types of circuit protection devices, minifuses, maxifuses, circuit breakers, and fusible links. The minifuses and maxifuses function similar to the current autofuse. The primary purpose of a fuse is to protect the wiring during short circuit conditions. In some cases, the fuse rating is intentionally undersized in order to protect the device to which the wiring is connected. Fuse rating selection is a function of total load current, nuisance blow safety factor, cable gage size, temperature, and circuit length.


A fuse is a device that, by the melting of its element, opens an electrical circuit, when the current exceeds a given level for a sufficient time. The action is non-reversible and the fuse is replaced after the circuit malfunction is repaired. Since the fuse functions by the melting of its element, it is a temperature sensitive device. This means that the fuse is affected by changes in ambient temperature, external heat sources (such as other fuses), and external heat sinks (such as conducting wires).