Cooling Fan Control

SYSTEM

COOLING FAN CONTROL : System Description


SYSTEM DIAGRAM







INPUT/OUTPUT SIGNAL CHART







SYSTEM DESCRIPTION

ECM sent cooling fan speed request signal corresponding to vehicle speed, engine coolant temperature, A/C
ON signal, refrigerant pressure, target A/C evaporator temperature, A/C evaporator temperature and blower fan ON signal.
Cooling fan speed request signal is sent to HPCM from ECM and traction motor inverter by CAN communication line. Then, HPCM sends cooling fan speed request signal to IPDM. 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.