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Engine - Coolant Temperature Sensor/Switch: Description and Operation

ENGINE COOLANT TEMPERATURE GAGE
The IPC displays the engine coolant temperature as determined by the PCM. The IPC receives a class 2 message from the PCM indicating the engine coolant temperature. The engine coolant temperature gage defaults to 75°C (160°F) or below when:
- The PCM detects a malfunction in the engine coolant temperature sensor circuit.
- The IPC detects a loss of class 2 communication with the PCM.