System Description: Description

ECM controls engine coolant temperature by the thermal management control.

For details of engine coolant circuit, refer to ENGINE COOLING SYSTEM SCHEMATIC .

The thermal management control has advantages as listed below.

• Enhancing warm-up
• Reducing toxic exhaust gas
• Improving fuel economy
• Increasing comfort of air condition

ECM controls engine coolant temperature according to the following sensors and signals.

• Engine coolant temperature sensor
• Charge air temperature sensor upstream of throttle valve
• Charge air temperature sensor downstream of throttle valve
• Pressure sensor downstream of throttle valve (engine load)
• Accelerator Pedal Position Sensor
• Crankshaft position sensor (engine speeds)
• A/C auto amp. (ambient temperature and A/C status)
• ABS actuator and electric unit (control unit) (each wheel speed)
• TCM (A/T oil temperature status)

The thermal management control has following control items and function.

• Control after start
• Coolant thermostat control
• Overheat protection function
• Cooling fan motor control