After reading every thread I can find on radiator fan problems, I'm fairly certain I need to order a new radiator fan assembly.

However, lest I just become a parts-replacing junkie (and not a mechanic) I figured I might as well get some some more information to troubleshoot from.

The situation: my radiator fan never runs. I very likely didn't notice this while it was cold outside... but now it's hot and I noticed when I saw the coolant temp needle rise yesterday. No high or low speed fan, ever. (AC on/off, hot/cold, nothing.) My power steering fan works fine.

All fuses appear to be intact. I located the plug(s) for the radiator fan (pictures below)

and zoomed in a bit...

and I find that the big connector has two red/blue wires and on brown wire. The small connector has one green/red wire and one brown wire. The browns are tied directly to ground (duh) and the larger of the red/blue wires appears to always carry +12V when the key is in position 1 or running. Anyone know what the other two wires are supposed to carry?

Any suggestions appreciated. Just trying to verify that my system is working before I spend money needlessly on a radiator fan that may actually work.

Thanks-