Okay, I understand how to wire a switch to ground the relay to cut the fan(s) on manually, so that's not what I'm asking. Here goes...


I'm going to use the factory foglight switch, since it's not used. The relay is MIA for the foglights , so that isn't an option. I'm just making sure I got this straight in my head.


There is also a small light installed under the foglight switch that was there when I bought the car...not factory, but looks fine. So I want this light to come on when the fan is on, regardless of whether or not I turned it on myself or not.


The PRIMARY use for this is at the dragstrip, I don't have any cooling problems.


So... I'm going to use a wire tap on the green / white wire on the primary fan relay, and then run that wire to one side of the foglight switch. The other side of the foglight switch goes to a good ground, thus when the the switch is turned on, the fan comes on, but the ECM is still able to cut the fan on when it needs to.

Next...for the light. I'm going to run one of the wires to a 12v batt powers source, I'll just use a wire tap at the fusebox, as I'm sure the tiny little light won't draw enough current / amperage to hurt anything.

Now this is where my coffee deprived brain is muddling it up...the 2nd wire on the light.... I want this to come on WHENEVER the fan is on, regardless of how it was turned on. So shouldn't I tap this into the green / white wire connection?

Making sure I've got this straight.


Thanks

 

Personally, I'd use a relay. A Bosch SPST, for example, wired to turn on with ground. You can put in some resistors, if you choose to, to minimize the current draw, and an inline fuse.

 

The green wire from the relay is already connected to a relay and will work fine. Not too sure about the light though. I don't think the light is a big deal, just pay attention to if the switch is up or down. When you race flip it up, and when you're done flip it down. No need for a light imho... if your fans come on correctly via the ECM listen for them, or forget about it. No need for a light. Other wise connect the light to just the switch and the light will remind you to turn the switch off.