1996 SS Camaro (not a clone, if that makes a difference)

Problem: fans are not kicking in properly. Only way the fans will engage is if a/c is on, furthermore fan one (low speed) Will kick on but fan two will not. If relay is manually kicked on fan two, it will run. All relays are getting power, but still will not engage. What sends signal to relays to engage fans?

Remedies Ive tried: new thermostat, replaced all relays, flushed radiator and added new antifreeze, replaced temperature control sensor, replaced sensor that screws directly into head. Fans are currently straight wired to keep from blowing my motor but I would like to resolve the problem and have things properly working. Also, there are no trouble codes pertaining to the fans or cooling.

Please help. I've been working since Friday on this problem. I have read the Haynes manual front to back....still clueless.

 

The PCM sends a ground to the relays to operate them.

http://shbox.com/1/fan_schematic_1995.jpg

http://shbox.com/1/4th_gen_tech2.html#cooling

 

Based upon the link to schematics, I checked all ground wires and connections. Nothin was amiss.
Based upon the second link, I did the "field enable" test, the fans would not engage. I straight wired the fans to continuously run as of Monday. Since then, another problem has arisen. Whenever I turn the ignition off, the car will pause for around 3 seconds, the gauges (speed and rev) will teeter totter and then the car will finally quit running. What is going on!?!

 

Depending on how you wired up the fans (lots of ways to do this), you might be back-feeding some power to the ignition system. Now that you know how the stock relay system works, you should be able to narrow down the problem. Saying you "checked all ground wires and connections" is not a detailed enough explanation.
When in field service enable mode, the PCM should output a ground on the relay control wires to operate them.