Can anyone answer this? I asume its to keep your car cooler,would like to do if easy diy!

 

It lets you control when your fans turn on. It also lets you run the fans after the car is off. Search for more specific info

 

yep, you just ground certine relays to manually control the speed of the fans (low med high)

 

Also, you can mod it so you have a switch to turn it on and off or you can mod it so that it runs on high all the time.

 

There are basically two flavors of fan mod for the car. One takes advantage of the testing function built into the fan circuit with the coolant system recall. During the recall, a fan control unit was placed into the circuit right by the ECU. It incorporates blue wire with yellow connectors, if I recall. The extra fan control unit is a small black box typically mounted tot he backside of the ECU, nearest the firewall. There should be a black wire with a female space connector coming from the box. If you ground this wire with the igntion set to run (not accessory), the fans should come on low. You can set this connection to a switch and manually control the fans, or ground it and the fans will always run when you run the engine. Note that always running the engine means you are always pulling heat out of the radiator directly into the IC, intake box, and battery. These heat up real well, and you will have higher intake temps than if you just get an adequate temperature monitiring set up (aftermarket gauge or linearize the stocker) and switch the fans on if you need them. Or replace the thermoswitch with a Miata or 2nd gen RX (turns fans on low at 208F instead of 221F (or 210F with enectrical load)). Also, the little black box is a timer, and notices if the circuit controlled by the black wire has been grounded by the thermoswitch for 2 minutes or more before shutting off the car. If this happens, the timer runs the fans for 10 minutes after shutoff to try and cool the engine (though why you would be shutting the engine off at 221F or higher after it's been running that hot for more than 2 minutes before you went to shut it off in the first place is beyond me.. unless you are of course relying on the stock temp gauge...). This could lead to dead batteries if you go this route...

Alternative is the so called Dysney mod (search for this). Here, you tap a switch directly into the fan control relays, grounding the appropriate ones for given fan speed. I have a three position small srocker switch in the middle position on my center console (where the dead switch plug goes for the headlight washer system on Canadian models). Forward position gives low speed even with ignition turned off and key removed. Rear position gives low fan speed with ignition off, medium speed with ignition set to run. With a linearized gauge, I never see more than 210F temps, usually clamp down by ~205F or so. Works for me. The Dysney mod was easy for me, but others don't like all that woirk. I soldered the control wires directly to the spade connector that is part of the relay plug(s), but I'm a nutcase

Hope this helped...

 

Here's the link:

http://rx7.voodoobox.net/

Go under how-to's and click "fan switch mod"

 

Easy fan mod link:

http://www.scuderiaciriani.com/rx7/fan_mod.html