fans refuse to turn on

hey so i knew i never heard my fans on, but since my temp was always relatively normal, i never thoguht twice. but then again, i only looked while i was driving. today i was cleaning the engine and let it idle, after about 6 mins or so of just idle my temp gauge was at the last line before the red. is there some secret to get the fans running?

Relays are good.  Temp sensors are good. (both of them?)  Fan work?  You have tested them correct?  PCM maybe?  No check engine lights?  Bad wiring.  Those are all of the problems that I can think of. 

Sounds like pretty normal operation to me- stock fans are set to come on around 220 degrees (thanks PETE!)- near the red line. There is also a sticky in the LT1 section about how the fans operate.