2000 3.0 vulcan cooling fans only work when coolant temp sensor unplugged have changed sensor fuse and relays help.
Fans on based on coolant temp (2 wire sensor), vehicle speed, and AC switch. If the coolant temp isn't hot enough it won't turn them on at all. Unplugging the ECT sensor makes the ECU think the temp is cold which is why it turns them on.
Search Ford Taurus Questions
Ford Taurus Experts