This is how I'd wire it. I have used those switches before and they won't carry many amps for very long, before they start getting hot and make the housing get soft from the heat then they fail, the contacts will take the current but not the housing. I like to use the gorund leg of the relay to function it..... This is a bosch type relay avail at any auto store or junkyard
Last edited by EOD Guy; 01-14-2013 at 08:41 PM.