My '85 FWD Fleetwood cooling fans run all the time. I have to assume that the module is bad. It's been that way since I've owned it. The module on this one is wrapped in the harness, (weird) and a new one seems unavailable. Anyone heard of a different year, or different GM car module being modded to fit?
I have that same controller on my 85. I used to see them on ebay but just looked and don't see any now. I figure I'll have to go with an aftermarket controller when the time comes but it will be tough to integrate with the BCM (it sets F41 and trips the coolant/fan light if it doesn't get the expected feedback). There are a few tests you can run to see if the problem is with the command wires from the BCM to the FCM, or with the monitor wire, or with the fans themselves. If you don't have an FSM a competent shop should be able to do the tests from alldata.