Engine coolant temperature (ECT) gauge

Fig 1: Identifying Engine Coolant Temperature Gauge Input And Output Signals

Courtesy of VOLVO CARS OF NORTH AMERICA.

The engine control module (ECM), (4/46) processes the value from the coolant temperature sensor (7/16). The processed value is then transmitted to the central electronic module (4/56) on the high speed section of the Control Area Network (CAN). The central electronic module receives the signal and generates a corresponding signal on the low speed section of the Control Area Network (CAN). The driver information module (5/1) reads the signal from the low speed section of the Control Area Network (CAN). The driver receives information about the temperature from the engine coolant temperature gauge in the combined instrument panel. If the value is too high a red lamp lights and a text message is displayed outlining the fault.