high fan speed after optical drive replacement HELP!!

I just replaced the optical drive in my mid 2007 imac and when it powered back on the fan inside is running at max speed, it sounds like it is getting ready to take off!! I replaced the hard drive a few months back and didn't have any problem at all. I replaced the temp sensor on the optical drive in the original location. Resetting the SMC controller doesn't help, also software fan controllers do nothing, what now? Is there something that I need to go back in & make sure is connected?

OOOPSSSSS! I went back in & found the temp sensor connector to the optical drive dangling free & easy on its own, connected it back in & whaddya know, no fan problem!!! I know what happened, I had such a hard time getting the screws back in to the optical drive data connector I forgot to do my little checklist, I just wanted to throw the whole #$#&@! thing back together. Maybe after I work on this a few more times I'll REALLY know my way around inside. If Macs were as easy as PCs to work on they would be perfect. Oh well maybe in heaven......

Good work. First things to check those little plugin sensors after having our big mitts inside and fans ramp up.