Self-test of over-current fault detection

A system for testing over-current fault detection includes a first switch 14 to connect a voltage to a load, a capacitor 20 connected between the first switch and ground, a monitor circuit 38 that monitors a current from the first switch to the load, and a microcontroller configured to detect an over-current fault condition based upon input from the monitor circuit. The microcontroller controls the state of the first switch to connect voltage to the load and verifies over-current detection based upon current generated during charging of the capacitor.