Conditions for Setting the DTC

WARNING: This page is about a different car, the 2006 Buick LaCrosse and 2006 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.

The ECM detects that the actual engine coolant temperature (ECT) is 10°C (18°) less than the calculated ECT.
The condition exists for more than 4 seconds.