My car get really hot somedays while just idleing, almost to the point of overheating. Turning on the A/C drops the temp down quickly, but shouldn't the fans turn themselves on at a pre-set temp? Maybe they aren't doing that for some reason, and that's why forcing them on with the A/C cools it down. So, what could be a reason for them not coming on? A fuse, relay, something like that? What temp should they be coming on anyway? The car is (I think) running on the stock programming. Thanks.

 

You can read some explanation about the system here.

 

Thanks Shoebox. I have the GM service manual around here somewhere but I don't really feel like digging around for it. I'll check the site out.