Theory Of Operation
WARNING: This page is about a different car, the 2016 Dodge Durango. However, it is still accessible from the selected car via links, so may be relevant.
The purpose of this diagnostic is to ensure that the engine coolant temperature has reached a certain value (pass temperature) within a calibrated amount of engine run time. Engine run time is based on the start-up coolant temperature; the lower the start-up temperature, the more time allowed for the engine coolant temperature to reach the pass temperature. If the engine coolant temperature does not reach the calibrated pass temperature before the engine run time reaches the maximum time allowed for this diagnostic, a failure will occur.