Engine Coolant Temperature Gauge

The powertrain control module (PCM) sends coolant temperature as determined by the coolant temperature sensor to the body control module (BCM) via controller area network (CAN) serial data. The instrument panel cluster (IPC) displays the engine coolant temperature with the gauge when the BCM sends a class 2 message to the IPC indicating coolant temperature percentage. The engine coolant temperature gauge defaults to cold (0°) or below if:

• The PCM detects a malfunction in the engine coolant temperature sensor circuit.
• The IPC detects a loss of class 2 communications with the BCM.
• The BCM detects a loss of CAN communications with the PCM.