Engine Coolant Temperature Gage
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
The instrument panel cluster (IPC) displays the engine coolant temperature as determined by the powertrain control module (PCM)/engine control module (ECM). The IPC receives a serial data message from the PCM/ECM indicating the engine coolant temperature. The engine coolant temperature gage defaults to 32°C (89.6°F) if there is a malfunction in the engine coolant temperature sensor or the IPC detects a loss of serial data communication with the PCM/ECM.