Infiniti EX35. Manual - part 581

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< FUNCTION DIAGNOSIS >

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COOLING FAN CONTROL

COOLING FAN CONTROL

System Diagram

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System Description

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INPUT/OUTPUT SIGNAL CHART

*1: The ECM determines the start signal status by the signals of engine speed and battery voltage.

*2: This signal is sent to ECM through CAN communication line.

SYSTEM DESCRIPTION

ECM controls cooling fan speed corresponding to vehicle speed, engine coolant temperature, air conditioner
ON signal, refrigerant pressure, target A/C evaporator temperature and A/C evaporator temperature.
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.

JMBIA0075GB

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

Unified meter and A/C amp.

Vehicle speed*

2

Air conditioner ON signal*

2

A/C evaporator temperature*

2

Target A/C evaporator temperature*

2

COOLING FAN CONTROL

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Component Parts Location

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1.

Battery current sensor

2.

IPDM E/R

3.

Cooling fan relay

4.

Mass air flow sensor (with intake air 
temperature sensor) (bank 1)

5.

Refrigerant pressure sensor

6.

Cooling fan motor-2

7.

Intake valve timing control solenoid 
valve

8.

Exhaust valve timing control magnet 
retarder

9.

Cooling fan control module

10. Cooling fan motor-1

11.

Mass air flow sensor (with intake air 
temperature sensor) (bank 2)

12. ICC brake hold relay (ICC models)

13. Ignition coil (with power transistor) 

and spark plug (bank 2)

14. Electric throttle control actuator 

(bank 2)

15. A/F sensor 1 (bank 2)

16. Fuel injector (bank 2)

17. Camshaft position sensor (PHASE)

18. Engine coolant temperature sensor

19. Knock sensor

20. Exhaust valve timing control position 

sensor

21. EVAP canister purge volume control 

solenoid valve

22. Fuel injector (bank 1)

23. Ignition coil (with power transistor) 

and spark plug (bank 1)

24. EVAP service port

25. A/F sensor 1 (bank 1)

26. Crankshaft position sensor (POS)

27. Electric throttle control actuator 

(bank 1)

JMBIA0002ZZ

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COOLING FAN CONTROL

1.

Mass air flow sensor (with intake air 
temperature sensor) (bank 1)

2.

Mass air flow sensor (with intake air 
temperature sensor) (bank 2)

1.

Electric throttle control actuator 
(bank 1)

2.

Electric throttle control actuator 
(bank 2)

1.

Cooling fan motor-2

2.

Cooling fan control module

3.

Cooling fan motor-1

4.

Cooling fan relay

 : Vehicle front

JMBIA0003ZZ

JMBIA0004ZZ

JMBIA0005ZZ

COOLING FAN CONTROL

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PBIB1907E

1.

A/F sensor 1 (bank 1)

2.

A/F sensor 1 (bank 2)

 : Vehicle front

1.

A/F sensor 1 (bank 1) harness con-
nector

2.

A/F sensor 1 (bank 2) harness con-
nector

 : Vehicle front

JMBIA0007ZZ

JMBIA0006ZZ

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