I'm not sure what the policy is on that particular vehicle, but on newer Saturns (98 or so), it's about 70 mph where the fan turns off (since the fan would only serve to interfere with the airflow from the vehicle moving through the air).
Thanks for your responses, but I still don't know what's wrong:
...a failing temp sensor probably won't throw a code because there's not a redundant sensor that can be used as a base measure for the PCM to report against - so whether it thinks it's 90 or 190 degrees only a manual test would determine.
I don't know if this will post right (it's a cut-and-paste from a Word doc) - if it does, this may be helpful. It's valid for ATS and CTS sensors for S-series from 1991 thru 1998.
DEGREES (F)
SENSOR RESISTANCE (OHMS)
-40 77k - 109k
-20 39k - 53k
0 21k - 27k 20 11k - 15k 40 6.6k - 8.4k 60 3.9k - 4.5k 80 2.4k - 2.7k 100 1.5k - 1.7k 120 .98k - 1.1k 140 650 - 730 160 430 - 480 180 302 - 334 200 215 - 235 220 159 - 172 248 104 - 113 284 63 - 68
What year is your car again? Older models have 2 temp sensors - one for the gauge and one for the computer. Your problem most likely lies in the coolant temp sensor.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.