Radiator fan 97 Neon

Codes?

If the fan is good and the fuse is good, the only things left are the sensor &/or relay (the sensor tells the relay to turn on the fan). The relay can be tested electrically, but the only way to test the sensor would be to hook it up to a meter and sit it in water that you bring up to temperature. Easiest approach is to test the relay -- if it checks out, just go replace the sensor.

(A friend once had a car with radiator sensors that routinely died. The first time we changed it, we added a pilot light -- to show if the fan came on -- and an override switch to turn on the fan manually. That way, if he saw his engine temp getting too high without the fan pilot light coming on, he knew the sensor had died and could just hit the switch to keep things cool.)