Engine Coolant Temperature Gauge

Coolant temperature data is broadcasted from the Powertrain Control Module (PCM) via the class II serial data line to the instrument cluster. The instrument cluster will then compare the temperature data with a sixteen-point look-up table to determine needle deflection. A smooth filter is used to secure a continuous response. The instrument cluster will drive the temperature gauge to C (cold) if the temperature data is lost or if the PCM is in a state of health fault.