INPUT/OUTPUT SIGNAL CHART

Sensor
Input signal to ECM
ECM function
Actuator
Crankshaft position sensor (POS)
Camshaft position sensor (PHASE)
Engine speed*1
Cooling fan control
IPDM E/R

Cooling fan control module

Cooling fan motor
Engine coolant temperature sensor
Engine coolant temperature
Refrigerant pressure sensor
Refrigerant pressure
Battery
Battery voltage*1
Combination meter
Vehicle speed*2
A/C auto amp.
Air conditioner ON signal*2
*1: ECM determines the start signal status by the signals of engine speed and battery voltage.
*2: This signal is sent to ECM via the CAN communication line.

 
 SYSTEM DESCRIPTION

ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, air conditioner ON signal, refrigerant pressure.
Cooling fan control signal is sent to IPDM E/R from ECM by CAN communication line. Then, IPDM E/R sends ON/OFF pulse duty signal to cooling fan control module. Corresponding to this ON/OFF pulse duty signal, cooling fan control module gives cooling fan motor operating voltage to cooling fan motors. Cooling fan speed is controlled by duty cycle of cooling fan motor operating voltage sent from cooling fan control module.
NOTE:
To cool off the engine, the cooling fan may continue to say ON for two minutes after turning OFF the ignition switch.