i'm reinstalling the second fan (from the a/c system) in my hatch and wiring it into a toggle on the dash to help keep things cooler, mostly for my smog test but it'll come in handy beyond that.

 

i'm just using what i already have: the fan, a spare relay, an illuminated toggle, a 15A inline, and wire cut from the leftovers of my spfi donor harness... how's that for frugal!

 

well, i'm no elecrtician so i wanted to run my wiring by the resident experts. the relay is the same as used for the fuel pump where terminals 1 & 2 have contant continuity and 3 & 4 are the relay switched terminals.

 

 

also, i should be able to tap into about any 12V supply under the dash since the light in the switch will only pull a little bit of current, right?

Should not the 15 A fuse be between the battery and number 3 position on the relay?

Should not the 15 A fuse be between the battery and number 3 position on the relay?

Aba4430 is correct, you should fuse the line from the battery to the fan. In the event anything downsteam of the battery should ground out (including the fan), you would smoke the wires (and maybe more) in that circuit. Also, if you're drawing power from underneath the dash for the lamp and relay coil, the line you use is likely already fused so you wouldn't need that fuse once you verify that fact.

thanks, i knew there would be something. i already finished and it works but i'll move the fuse to the relay's main power line as suggested and verify that there's already a fuse in the power supply to the switch.

can i supply my switch and the fan from the battery with the same fuse? it would be something like this:

 

 

i like how i have things under my dash right now and i don't want to have to start cutting zip ties to redo things under there yet again... but if its not safe this way, i'll venture into that bird's nest again. thanks

My 2 cents...

I personally, to "power" the switch, would grab a "pre-fused" switched power from the fuse box. That way, it'd:

A. be a separate fuse, not that it takes a lot of current.

B. be shorter wiring.

and finally C. could not be left on all day. In your circuit you can turn/leave the fan on anytime... possibly draining the battery.

can i supply my switch and the fan from the battery with the same fuse? /quote]Yes that would work just fine.

My 2 cents...

I personally, to "power" the switch, would grab a "pre-fused" switched power from the fuse box. That way, it'd:

A. be a separate fuse, not that it takes a lot of current.

B. be shorter wiring.

and finally C. could not be left on all day. In your circuit you can turn/leave the fan on anytime... possibly draining the battery.

Good point!

yeah, i thought it was a good point, too.

 

so, i was going to use the slot in my fuse box labeled (ECM) since my spfi ecu is obviously powered by other sources and there wouldn't be anything else pulling on that fuse. multimeter shows this one isn't switched though, its got a constant 12V.

 

i guess i need to pull from the "accessory" section of the fuse box, not the "battery" section. i'm thinking the cigar/mirror one since i don't use the lighter/socket and i don't have power mirrors (i didn't even know those were available on ea81's).