The relay is powered up and activated thanks to a small electrical current. When it is activated, it lets a current that is much bigger than the original one flow through other two outlets. It is used to control the headlights, the rear fog light, the electric fan, etc.
Owner was driving vehicle, heard some kind of sizzle noise , then the engine died. Now when you go to start the vehicle, no relay click,just a slight hum from the
E passenger, side top of engine,round tubular component, perpendicular to engine,going into valve channel.