2002 3.8 Usually never have the fan come on. Its cold in Oregon this year and the car never runs hot anyway--I rarely hear fan. Tonight I noticed the fan came on very loud when I started it up. About five miles down the road, the temperature guage went to zero. five more and the 'service engine soon' light came on. I checked and it hadnt lost its coolant. Fan stayed on the whole trip though and its never done that before. All other instruments work fine but temp.