Coolant Temp Gauge
The ECM controls the coolant temperature gauge by sending
ECT messages to the Body Control Module
(BCM) over the Controller Area Network
(CAN) link based on ECT sensor readings. The BCM averages the temperature over time allowing the gauge to move slowly and remain in a relatively stable position as temperature varies. The BCM then sends the averaged information to the I/P cluster over the Class II link to position the gauge.