Diagnostic Aids

WARNING: This page is about a different car, the 2017 Cadillac ATS. However, it is still accessible from the selected car via links, so may be relevant.

NOTE:

The engine coolant temperature (ECT) sensor 1 is mounted on the engine and the engine coolant temperature (ECT) sensor 2, radiator coolant temperature (RCT) sensor, is mounted on the radiator.

The engine coolant temperature gauge will display full cold when an ECT DTC set's.
After starting the engine, the engine coolant temperature (ECT) sensor 1 temperature should rise steadily, then stabilize after the thermostat opens.