Cooling Fan Circuit Questions

[Gearhead Geek]

Ok, so here's what I'd like to do:
I'd like to wire up a little light or something in one of the empty pannels near the steering wheel, and have it light up when the radiator fan is on. Now, I'm looking at the circuit diagram in the service manual (Page 10-13), and it's confusing me slightly, so I'm hoping someone out there can answer a few things for me.
First off, the fact that the A/C and Radiator Fan relays share the same wire (Black/Yellow) for the control side of the relay is confusing me a bit. Now, I see that it branches off to the A/C system before the relays, and that makes sense, but as I follow it along, as it comes out of the relays as the Green/White wire, it goes into the ECM, and then to the radiator switch, then to ground. Now, does this mean that the AC condensor fan only turns on when the radiator fan switch is closed? Also, why does it go into the ECM before the radiator fan switch? I would think it would make more sense for it to get the reading from it afterwords. Lastly, let's say I wanted to have this light getting 12v off of an accessory position wire, then have the circuit close, thus grounding it, to turn it on. Would I just run my ground wire to where the Green/White wire goes to the radiator fan switch (pin #2), or is there an easier way?

If I worded any of this poorly or wasn't clear on something, I'll be more than happy to try and rephrase. Thanks in advance.

[Gearhead Geek]

Anyone?

[BlasTech]

Hmmm. My understaning is that the turning on the interior fan and AC will kick the cooling fan on... that could explain why they are together.

A thermo-switch activates the relay to turn the cooling fan on otherwise, but dont rob the voltage from your fan to power something...you could serve the same purpose with another dedicated thermo-switch.

Im curious, why do you want to have the light for the fan? I'd go for a fan override switch to make it kick on instead, some racers do that to force-cool thier cars.

[Gearhead Geek]

Well, yes, a fan override switch would be a good thing to have, and I've given thought to that also. However, the reason I want the light is mostly for the ECU relearn procedure (I know a lot of people think it's pointless, but I for one am a firm believer that it does help to do it every now and again, especially after modding, which I'll be doing a lot of lately). With my exhaust (Invidia cat back) it's just pretty much impossible to hear when the cooling fan kicks on while holding the rpms steady at 3k.