From what I gather from reading a ton of posts via search, the primary fan (drivers side) is controlled by the computer, via the CTS which is under the throttle body. The secondary fan (passenger side) is controlled by the single wire fan switch in the engine, or the ac switch.

My primary fan does not come on automatically, we have hooked up switches to turn both fans on manually like in this diagram.

http://65.98.116.234/~rob/fandiag.jpg

So, the switches confirm both fans indeed work, and they do not interfere with regular operation.

I hooked the car up to TunerPro RT to check what temperatures the computer sees. "Coolant Temp" is always -39.99 and sometimes the font color turns red and sometimes it goes back to blue. I forget what the original value of "Startup Coolant Temp" was when I plugged in it, but it wouldnt really change at all as the car got hotter. We disconnected the harness connector to the CTS and applied resistance with a potentiometer (with the car in ignition, engine NOT on) to it, we made the computer see 118.63C which is about 245F (in the Startup temp box) which means the fan should be turned on by the computer, we werent sure if the car had to be on so we started the car. The fan did not turn on, ontop of that, the computer would NOT recognize any more changes in resistance from the potentiometer AFTER the engine is started, it would just be stuck at 118.63, or whatever value we had it set to before we started the engine.

The Fan Request Status always said Not Requested

Here is the TunerPro log file http://65.98.116.234/~rob/problem.adl

 

Anyone?

 

sting, you might click-on User CP at the top of this page, then click-on Cooling and a new page should come up with different methods of getting an f-body running cool. I have used some of the mods by Willie so I know they work. As far as your questions about the computer, sorry I can`t help you. Look through Willie`s info and something there will probably work for you. You can also PM him, he`s good about answering unless he is on vacation and he will answer when he`s home.

 

My signature line has some good diagnostic stuff on fans.

 

sounds like im having the same problem as you with my car...did not test it the way that you did but i ahve my own thread about my problem

https://www.thirdgen.org/forums/cool...y-primary.html

see if we can help eachother out...wish i had tunercat