Jackie, the power comes straight from the battery. Nothing comes directly from the IRCM. The signal to the relay goes from the red wire out of the ignition switch that goes to activate the ign-on circuits in the dash fuse panel. My tap-in runs to a switch, then the relay, and the relay grounds to the common ground on the header panel just in front of the battery. the fan power comes from the battery, through an in-line fuse, to the relay, out of the relay, and to the fan. As soon as I activate it the buss fuse blows. I can check it with a different relay to see if it has an internal short. I doubt these relays have an internal diode, as they cost me 8 dollars at Radio Shack. Also, because my 20 amp radiator fan (aftermarket universal) keeps blowing 30 amp relays. it comes on a couple times without drama, then ceases to come on again. I assume it spikes when it shuts off and that blows the relay. I will go to the electronics supply store tomorrow and get a 30 amp diode for it to solve that problem.