Fun with Relays
previously posted link was bad...
Eventually, because I had upgraded to larger/stronger SPAL fans, under full load, the switch was frying when A/C, headlights, then fans would go on. Not only was the switch overloaded, the wires were also too small to handle the amperage requirements of the new fans. Funny thing was, the fan specs said 60+amps when kick-in occurred; yet never blew the 20amp fan fuse. Then the 20 amp fuse did not let enough amps in to initially trip the relay...bigger wire and 30 amp fuse solved the "clicking" problem I had with the fan relay. I have to rethink this because the fix seems to negate the fuse protection objective, inspite of everything working fine now.