Re: 97 Contour Radiator fan only works when A/C is on
I can't swear to it, but I think therr are two sending units. One for the gauge and one for the fan to come on. I believe all it does is create a ground at a certain temp to signal the fan to come on. You could try to pull the wire and ground it and see if the fan comes on. If it does, the sending unit is bad.
(You have checked fluid level haven't you?)