DTC P2181-F0: Cooling System Performance: General Description
Integrated Thermal Management Module (ITM) is a device that controls the flow rate of coolant according to the temperature of the coolant. At initial start up, the ITM adjusts the valve to allow coolant to flow only to the engine, helping to warm up quickly and improve fuel efficiency through rapid warm-up. When the coolant temperature increases, the ITM adjusts the flow and temperature of the coolant with the radiator or heater.
The Engine Coolant Temperature Sensor (ECTS) uses a thermistor whose resistance changes with the temperature. The electrical resistance of the ECTS decreases as the temperature increases, and increases as the temperature decreases. The reference +5V is supplied to the ECTS via a resistor in the ECM. That is, the resistor in the ECM and the thermistor in the ECTS are connected in series. when the resistance value of the thermistor in the ECTS changes according to the engine coolant temperature, the output voltage also changes. During cold engine operation, the ECM increases the fuel injection duration and controls the ignition timing using the information of engine coolant temperature to avoid engine stalling and improve drivability.
ECTS #1 is located near the ITM, ECTS #2 is located near the water pump, and both sensors are used for ITM control. ECTS #3 is located near the cylinder block and is used for split cooling control.