Electric Fan Switch

[ITSANSS]

Hey, ya'll.

Got a 1988 Chevrolet Monte Carlo SS. Sick of using a toggle switch to manually turn on my dual electric fans. Heard the factory Buick guys have a switch that turns on electric fans at 205* F. Was wanting to get a little information on it if anyone has some knowledge in that department. (A search didn't give me what I wanted.) Supposedly using a Regal switch along with an adapter will screw into my carbureted intake manifold and be functional.

Ran by my local Advance Auto Parts and they have the switch itself for $40. Has to be ordered, of course.

If ya'll want to hear my whole story about my electric fan woes, I posted it on MonteCarloSS.com. (Forum List, Technical, All Things Electrical, Electric Fan FAQ sticky, last page, ITSANSS...won't let me post direct link because of my lack of posts on this website.)

Thanks!

 

[buickin87]

You can find the GN factory wiring for single fan in the wiring department below. So, there is not only the coolant temp switch/205F(about) indebendent of the ECM, which turns the fan on in that themperature. In additional to that there is also coolant temp sensor, which sends the information into ECM, where is the fan on- settings programmed into chip- about 195 F or so in the stock chip. the single fan operates in two speed debending on which circuit- ECM or that temp switch is triggering the fan on.
The voltage into fan triggered by temp switch is bypassing the resistor near the fan(hi-speed) and the voltage triggered by coolant sensor/ECM is going trough the resistor( lo- speed). The temp sensor and the coolant switch are located in the intake manifold.

Hope this will give you some hints how to build your own system.



Wiring Diagrams

 

[ITSANSS]

Cool! I really appreciate the link. Very informative. I figured ya'll only had a single cooling fan from the factory. One thing I am not worried about having whatsoever is high and low fan speeds. I would much rather have both fans come on at full blast when the time is right. Which is why I have both of my fans wired together to where my single toggle switch fires 'em both off at once, full-blast.

Since the ECM also has some input aside from the coolant temperature switch, I am now wondering if it would still do what I wanted it to do without a computer. I think it would be ideal to turn on around 205* F and shut back down around 180*F, which is the thermostat I run.

I wonder if the intake manifold switch is spring loaded or somethin'. Like a thermostat! Maybe? That would be awesome if it did everything by itself. Fans on, fans off. Wishful thinking?

Thanks again