High Temperature Indicator
The high temperature indicator function handles the control of the engine temperature gauge display and the red high temperature indicator. The PCM reads the coolant temperature sensor, filters the messages, and sends the coolant temperature to the instrument cluster via a Class 2 serial data message. The PCM monitors the coolant sensor in order to determine a fault. The PCM transmits the Class 2 serial data coolant temperature report messages to the instrument cluster for the temperature gauge display and for the high temperature indicator control.The instrument cluster receives the engine temperature data in the Class 2 serial data message from the PCM. The instrument cluster converts this data into a temperature gauge pointer position which drives the gauge pointer. The instrument cluster also uses this data in order to determine the high temperature indicator control.
The BCM looks for the high temperature indicator Class 2 serial data report from the instrument cluster and triggers a chime when the indicator is on.