Out of the blue yesterday as I was driving to work I turned on my headlights. When I did this every other light in the car shut off, turn signals, dash display, radio display. Is this most likely a fuse issue or something else?

Oh and when I turn the headlights OFF all that stuff comes back on by the way.

I suspect a problem with the combination light switch. Disconnect the negative battery cable and check/replace the combination light switch.