Coolant Temperature Gauge

The temperature gauge is an analog device that is located in the Instrument Panel Cluster (IPC). The temperature gauge is operated by the IPC with software control. The VCM/PCM uses Class 2 communications in order to inform the IPC of the engine coolant temperature. The IPC operates the Temperature Gauge to appropriately display the engine coolant temperature. The VCM/PCM determines the coolant temperature by measuring the current from a variable resistance sensor in the engine coolant jacket with the ignition switch in the RUN position. The sensor changes resistance with the coolant temperature. As the coolant temperature increases the resistance of the sensor decreases. The Coolant Temperature Sensor (CTS) is located in the thermostat housing on the 2.2L engine. The CTS of the 4.3L engine is located on the left side of the cylinder head.