Need a little wiring help.

[1-tonmudder]

I bought a thermostatic switch that screws into the block for my electric fan and need a little info on the wiring.

I'm using a 5pin 40A relay and want to put a on/off flip switch to kill it when the truck is off.How do I need to wire the relay,I assume since the switch in the block only has one connection that it will need to be grounded????

 

[GotBoykins]

You could run the switch between the temp switch and the relay.

 

[dyeager535]

Without thinking about it too much, couldn't you simply power the switch through an ignition 12V source, so that you don't have to worry about turning it off, except for water/mud/?

 

[1-tonmudder]

I have it wired on a flip switch now with no relay(just a breaker) and it keeps burning out switches.Thats why Im wanting to use a relay.I would also like to have it come on/off as needed.I have gotten busy before and forgot to turn it on.

 

[dyeager535]

Well that's what I mean.

Use the relay, as you want and as it should be, but use the switch only as a kill for water/mud.

If you've got a temp switch, then let it do the work. Use a 12V ignition source to control it during normal operation (thought free) and use the manual switch simply to interrupt relay operation when the truck is running.

Edit: I believe the wiring diagrams that have been floating around on here are setup like this.