So here's an interesting one...when I press the brake pedal my dome light turns on. If I have the map lights on, pressing the brake pedal shuts the map lights off and turns the dome light on. And none of them can be turned on by the dimmer switch.
So I figure the brake light circuit is backfeeding down a ground for the interior light circuit, but where in the car are those circuits close together? Could it just be a bad headlight switch? Just looking for ideas as to where to start hunting.