Diagnostic Aids
WARNING: This page is about a different car, the 2002 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
This DTC indicates lower than normal coolant temperatures and probably does not indicate a faulty ECT sub-system. Check for a stuck thermostat, cooling fan always on, a skewed ECT sensor, very low ambient temperatures or resistance in wiring. See ECT & IAT SENSOR RESISTANCE-TO-TEMPERATURE VALUES table. A shifted sensor could result in poor driveability complaints.